CPWD SPECIFICATIONS

government of india central public works department 2009 cpwd specifications (vol. 1) published by director general of works, cpwd, nirman bhawan, new...

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GOVERNMENT OF INDIA CENTRAL PUBLIC WORKS DEPARTMENT

CPWD SPECIFICATIONS (VOL. 1)

2009 PUBLISHED BY

DIRECTOR GENERAL OF WORKS, CPWD, NIRMAN BHAWAN, NEW DELHI

© All rights reserved. No part of this publication may be reproduced in any form or by any means, electronic or mechanical, including photocopying, recording on any information storage and retrieval system, without permission, in writing, from the Director General of Works, CPWD, New Delhi. Photocopying of this book is strictly prohibited.

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FOREWORD The CPWD Specifications being published by CPWD from time to time are very comprehensive and useful in execution of works and are used as guide by a number of Engineering Departments, Public Sector Undertakings, Architects and Builders. These specifications not only give the standards for building materials but also serve as guidelines for execution of works, measurements and rates. The CPWD Specifications were first compiled in 1950. Subsequently, these specifications have been revised in the years 1962, 1967, 1977 and 1996. Many new items and construction technologies, which are used in various CPWD works and projects have been incorporated in Delhi Schedule of Rates of CPWD. Some items have become obsolete over a period of time and are not in use. Further, there were no specifications for pile work, aluminium work, water proofing, & Horticulture and Landscape. CPWD Specifications have been accordingly modified/ revised and updated to incorporate the above changes. The revised/updated specifications are being published in two volumes. I wish to place on record the effective coordination on the part of Shri B.K.Chugh, ADG(WS)(TD) and the technical inputs and the efforts by Shri Virendra Sharma, C.E.(CSQ), Sh.Mayank Tilak, SE(TAS), Sh. S.K.Jain, EE, Sh. S.C.Malik, EE and Sh. P.P.Singh, EE in finalising these specifications. I am sure that these Specifications will be useful to all concerned in the building industry in general and CPWD in particular.

( D.S. Sachdev) Director General (Works) New Delhi July, 2009

PREFACE 1.0

CPWD Specifications, 2009 are the revised edition of existing CPWD Specifications.

2.0

CPWD Specifications, 2009 shall be a bilingual document (Hindi version will follow).

3.0

CPWD Specifications, 2009 is published in two volumes as under:

Volume Number

One

Two

4.0

Sub-head No.

Contents/ Chapters

0.0

General

1.0

Carriage of Materials

2.0

Earth Work

3.0

Mortars

4.0

Concrete Work

5.0

Reinforced Cement Concrete Work

6.0

Brick Work

7.0

Stone Work

8.0

Marble Work

9.0

Wood Work and PVC Work

10.0

Steel Work

11.0

Flooring

12.0

Roofing

13.0

Finishing

14.0

Repairs to Buildings

15.0

Dismantling and Demolishing

16.0

Road Work

17.0

Sanitary Installation

18.0

Water Supply

19.0

Drainage

20.0

Pile Work

21.0

Aluminium Work

22.0

Water Proofing

23.0

Horticulture and Landscape

CPWD Specifications, 2009 will replace existing CPWD Specifications, 1996 along with correction slips. The specifications of many items have been updated and improved by making them more comprehensive. Specifications of items, which have become obsolete over a period

(v)

of time or are not in use, have been deleted. Many new items using new materials and latest technology have also been added. 5.0

Details of new construction technology/ mechanisation have been introduced for execution of different works by using various electrical and mechanical equipments i.e. excavators, tower cranes, mobile cranes, mechanical platforms, Batch Mix plant, transit mixers and pumps, piling rigs, pneumatic cutters, chisels, chippers, hammers etc.

6.0

Specifications of dry work for speedier construction using prefabricated materials and prefinished elements are included viz gypsum block walls, calcium silicate and non-asbestos cement board partitions, pre-finished counter tops for kitchen and washbasins, pre-moulded and pre-finished stone work in risers and treads of steps and window sills, dry stone cladding, sub-frames for windows, use of chemical and mechanical fasteners, laying of tiles in flooring and dado with polymer based adhesives etc.

7.0

Specifications of pile work, aluminium work, water proofing and horticulture and landscape are incorporated for the first time.

8.0

Sub-head wise salient features are as follows:

8.1

Carriage of Materials: Provision of route other than shortest route in case of unavoidable circumstances introduced. Standards of stacking and storage of various construction materials incorporated.

8.2

Earth Work: Specifications for Earth work by mechanical means, i.e excavators and transporting equipment are introduced. Specifications for earth work for major works, import of earth and earth levelling works have been incorporated. Use of Aldrin is deleted and Lindane is introduced as anti-termite chemical. Further, constructional measures have been provided instead of pre-construction anti-termite treatment.

8.3

Mortars: Specifications of lime mortar which is not in use now a days have been deleted. Standards of fly-ash have been up-dated.

8.4

Concrete Work: Specifications of lime concrete which are not in use now a days have been deleted.

8.5

Reinforced Cement Concrete: Specifications of fly ash admixed cement concrete (FACC) and fly ash blended cements (PPCC), HSD bars of grade Fe 415D, Fe 500D and Fe 550D, physical properties and chemical composition of TMT bars, stripping time of formwork for RCC work using OPC 43 grade cement and PPC, surface treatment of shuttering by polymer based water soluble compounds, gas pressure welding and RMC incorporated.

8.6

Brick Work: Specifications of mechanized autoclave fly ash lime bricks, sewer bricks, burnt clay perforated building bricks and gypsum partition panels incorporated.

8.7

Stone Work: Specifications of gang saw cut stone, providing and fixing dry stone cladding and structural steel frame work for stone cladding have been added. Specifications of stone masonry in cement mortar with fine sand and with lime mortar are deleted.

8.8

Marble Work: Types of Marbles which are not easily available in market have been deleted.

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8.9

Wood Work and PVC Work : Wood work in doors & windows for frames / shutters in deodar wood deleted as deodar wood is not easily available. Specifications of other species of wood, available in market have been incorporated. Specifications of LVL, UPVC, solid PVC, FRP flush & panelled door shutters & frames, wall panelling of calcium silicate boards and FRP chajjas included.

8.10

Steel Work: Steel glazed doors & windows fixed, side hung, top hung, centre hung, composite units including mullion bar and steel beadings are clubbed together and to be paid in Kg in one item instead of earlier being measured in sqm. Profiles of pressed steel door & window frames revised. Specifications for factory made windows and doors, ERW tubular pipes for handrails etc incorporated.

8.11

Flooring: Specifications pertaining to obsolete items deleted. Specifications for laying tiles in flooring and dado with polymer based adhesives included.

8.12

Roofing: Non-asbestos cement sheet provided in place of asbestos cement sheet roofing. Items of corrugated G.S. sheet roofing 1.60 mm thick & 1.25 mm thick deleted as these are not readily available. 20 mm thick wooden planks ceiling, 18 mm insulating board, 18 mm flame retardant board on roofs deleted as boards of these thicknesses are not readily available. Lime concrete terracing deleted.

8.13

Finishing: Items of plaster with lime deleted. Specifications of gypsum plaster and exterior painting on walls added.

8.14

Repairs to Buildings: Items pertaining to repairs in various sub-heads are shifted to this head. Specifications are up-dated.

8.15

Dismantling and Demolishing: Specifications of dismantling and demolishing of different elements of structures and safety measures included.

8.16

Road Work: Items of preparation and consolidation of sub grade clubbed together. Supplying R.C.C. posts /struts /rails /pales at site are clubbed together and to be paid in cubic meter instead of numbers. Mix modified to 1:1.5:3 instead of 1:2:4. New items of Concertina coil fencing & Chain link fencing, Dense Bituminous Macadam, Bituminous Macadam, Dense Bituminous Concrete with CRMB & PMB are added. Various signages viz Caution / regulatory retro reflective boards & over head signage boards, Road marking (retro-reflective) are also included. Kerb channel, post delineators, Factory made RCC pavement slabs, CC interlocking paver blocks & kerb stones, vacuum de-watered CC pavement, scarifying BM by mechanical means etc have also been included.

8.17

Sanitary Installations: Items of long pan W.C., C..P. brass trap & union, G.I. chain with G.I. pull are not in use now a days and hence deleted. Specifications of PVC cisterns and stainless steel kitchen sink have been added.

8.18

Water Supply: Specifications of PE-AL-PE pipes, PP-R pipes and CPVC pipes included. Items not in use have been deleted.

8.19

Drainage: Specifications of Stone ware pipes, RCC pipes etc updated and items not in use deleted. (vii)

8.20

Specifications of sub-heads of ‘Pile Work’, ‘Aluminium Work’, ‘Water Proofing’ and ‘Horticulture & Landscape’ are added for the first time.

9.0.

A lot of effort has gone into the preparation of CPWD Specifications, 2009. I convey my deep appreciation and sincere thanks to Shri Virendra Sharma, CE, CSQ, Shri Mayank Tilak, S.E. (TAS), Sh. S.K.Jain, EE (S&S), Sh. S.C Malik, EE (S&S), Sh. P.P. Singh, EE (S&S), Sh. G.K. Jindal, AE, Sh. V.P.Singh, AE, Sh. Natthi Lal, AE, Sh. R.K. Vashisth, AE, Sh. L.C. Gothwal, AE and other officers and staff of TAS Unit for sincere efforts made in the preparation of this document in such a short time.

10.

Due care has been taken to print CPWD Specifications, 2009 as correctly as possible. It is, however, possible that some errors might have crept in. In case any error or omission is noticed, it may be brought to the notice of the Superintending Engineer (TAS), CPWD, Room No. 418, A- Wing, Nirman Bhawan, New Delhi.

11.

In case of any discrepancy between English and Hindi versions, the English version shall be held valid. Suggestions for improvement are welcome.

(Bhishma Kumar Chugh) ADG (WS) (TD), CPWD, Nirman Bhawan, New Delhi

(viii)

COMMITTEES FOR DRAFTING OF CPWD SPECIFICATIONS – 2009

CPWD specifications are very comprehensive and contain not only standards of the construction materials but also guidelines for execution of works, testing for quality assurance and mode of measurements for billing. CPWD Specifications are part of contract document also and it shall take cognizance of field conditions. It was, therefore, felt necessary to take inputs from as many officers as possible and incorporate their experiences. Accordingly, the following committees were constituted: 1 Drafting Committee (i) (ii) (iii) (v) (v)

Sh.Virendra Sharma, CE(CSQ) Sh.Mayank Tilak, SE(TAS) Sh.S.K.Jain, EE(S&S) Sh.S.C.Malik, EE(S&S) Sh.P.P.Singh, EE(S&S)

Chairman Member Member Member Member

2. Committee for revision of sub – heads 1 to 5 & 20 of CPWD Specifications- 2009 (i) (ii) (iii) (iv) (v)

Sh. R.N Dandekar, C. E Sh S.L.Meena, SE Sh. Bhagwan Singh, SE Sh Rajeev Kumar, EE Sh V.K.Asol, EE

Chairman Member Member Member Member

3. Committee for revision of sub – heads 6 to 13 & 21 of CPWD Specifications- 2009 (i) (ii) (iii) (iv) (v) (vi) (vii)

Sh. Rakesh Misra C. E Sh A.K.Aggarwal, SE Sh. Ram Dayal, SE Sh. A.K.Sharma, SE Sh A.K.Grover, EE Sh Sher Singh, EE Sh. A.K.Singh, EE

Chairman Member Member Member Member Member Member

4.. Committee for revision of sub – heads 14, 15, 17 to 19 & 22 of CPWD Specifications - 2009 (i) (ii) (iii) (iv) (v)

Sh. S.M. Amrit, C. E Sh Deepak Gupta, SE Sh. V.K.Sharma, SE Sh Sanjeev Rastogi, EE Sh R.K.Kayesth, EE

Chairman Member Member Member Member

(ix)

5. Committee for revision of CPWD Specifications for sub-head 23 of CPWD Specifications 2009 (i) (ii) (iii) (iv) (v)

Dr. V.K.Verma, DDG (Horticulture), since retired Sh Dhan Singh, Director (H) Sh. S.C.Dixit, DD (H) Sh B.N.Srivastava, DD (H) Sh Sukhbir Singh, DD (H), since retired

Chairman Member Member Member Member

I convey my sincere thanks to above members of committees for preparation of this document. I also thank Shri Jose Kurien, CE (Retd), CPWD and Shri B.B. Makkar, SE, CPWD, who were not members of any committee, but have widely contributed in finalisation of these specifications in general and in subheads of “Pile Work” and “Aluminium Work” & “Water Proofing Work”, respectively in particular. I also express my sincere thanks to Shri S.R. Pandey, ADG (Retd.) CPWD and Shri Kamlesh Shukla, A.E., CPWD for their useful suggestions for specifications of “Road Work”. I am sure that CPWD Specifications, 2009 will be useful to all concerned. Due care has been taken to print CPWD Specifications, 2009. It is however, possible that some errors might have crept in. In case any error or omission is noticed, it may be brought to the notice of the Superintending Engineer (TAS), CPWD, Room no. 418, A-Wing, Nirman Bhawan, New Delhi.

(Virendra Sharma) Chief Engineer (CSQ), CPWD

(x)

CONTENTS Vol. 1 SH. No.

Name of Sub-Head

0.0

GENERAL

1-8

1.0

CARRIAGE OF MATERIALS

9-24

2.0

EARTH WORK

25-60

3.0

MORTARS

61-82

4.0

CONCRETE WORK

83-112

5.0

REINFORCED CEMENT CONCRETE WORK

113-200

6.0

BRICK WORK

201-236

7.0

STONE WORK

237-272

8.0

MARBLE WORK

273-290

9.0

WOOD WORK AND PVC WORK

291-392

10.0

STEEL WORK

393-442

11.0

FLOORING

443-480

12.0

ROOFING

481-532

For remaining Sub Heads see Vol. 2

Page No.

SUB HEAD : 0.0

GENERAL

CONTENTS Clause No. 0.1

Brief Description

Page No. 5

0.2

5

0.3

Interpretations

5

0.4

Definitions

5

0.5

Floor and Levels

5

0.6

Foundations and Plinth

6

0.7

Measurements

6

0.8

Materials

6

0.9

Safety in Construction

7

0.10

Abbreviations

7

3

SUB HEAD 0.0 : GENERAL

CPWD SPECIFICATIONS 2009

4

0.0 GENERAL 0.1 Reference mentioned herein shall be applicable to all sections to the extent the context permits and are intended to supplement the provisions in the particular section. In case of any discrepancy/ deviation, the provisions in the particular section shall take precedence. 0.2 The rates for all items of work unless clearly specified otherwise shall include cost of all labour, materials and other inputs involved in the execution of the items. 0.3 INTERPRETATIONS 0.3.1 The Director General (Works), CPWD shall be the sole deciding authority as to the meaning, interpretation and implications for various provisions of the specifications. His decision in writing shall be final. 0.3.2 Wherever any reference is made to any Indian Standard, it shall be taken as reference to the latest edition with all amendments issued thereto. In the event of any variation between the CPWD specifications and the Indian Standard, the former shall take precedence over the latter. 0.4

DEFINITIONS The following terms and expressions in the specifications shall have the meaning or implication hereby assigned to them unless otherwise specified elsewhere. 0.4.1 Contractor: The Contractor shall mean the individual or firm or company whether incorporated or not undertaking the works and shall include the legal personal representatives of such individual or the persons composing such firm or company, or the successors of such individual or firm or company and the permitted assignees of such individual or firm of company. 0.4.2 Engineer-in-Charge: The ‘Engineer-in-Charge’ means the Engineer officer who shall supervise and be in-charge of the work and who shall sign the contract on behalf of the President. 0.4.3 Site: The ‘site’ shall mean the land/ or other places on, in, into or through which the work is to be executed under the contract or any adjacent land, path or street through which the work is to be executed under the contract, or any adjacent land, path or street which may be allotted or used for the purpose of carrying out the contract. 0.4.4 Store: The ‘store’ shall mean the place of issue of materials included in the appropriate schedule of a contract for issue by the CPWD. In all other cases ‘Store’ shall mean any CPWD store in the district. 0.4.5 IS: The standards, specification and code of practices issued by the Bureau of Indian Standards. 0.4.6 Best: The word ‘best’ when used shall mean that in the opinion of the Engineer-in-Charge, there is no superior material/ article and workmanship obtainable in the market and trade respectively. As far as possible the standard required shall be specified in preference to the word ‘best’. 0.4.7 Department: ‘Department’ shall mean Central Public Works Department (CPWD). 0.5 FLOOR AND LEVELS 0.5.1 Building 0.5.1.1 Floor 1 is the lowest floor above the ground level in the building unless otherwise specified in a particular case. The floors above floor 1 shall be numbered in sequence as floor 2, floor 3 and so on. The number shall increase upwards. 0.5.1.2 Floor level: For floor 1, top level of finished floor shall be the floor level and for all other floors above floor 1, top level of the structural slabs shall be the floor level.

5

SUB HEAD 0.0 : GENERAL

0.5.1.3 Plinth level: Floor 1 level or 1.2 m above the ground level whichever is lower shall be the plinth level. 0.5.2 Special Structures 0.5.2.1 For structures like retaining walls, wing walls, chimneys, over head reservoirs/ tanks and other elevated structures, where elevations/ heights above a defined datum level have not been specified and identification of floors cannot be done as in case of building. Level, at 1.2 m above the ground level shall be the floor 1 level as well as plinth level. Level at a height of 3.5 m above floor 1 level will be reckoned as floor 2 level and level at a height of 3.5 m above the floor 2 level will be floor 3 level and so on, where the total height above floor 1 level is not a whole number multiple of 3.5 metre. Top most floor level shall be the next in sequence to the floor level below even if the difference in height between the two upper most floor levels is less than 3.5 metres 0.6

FOUNDATION AND PLINTH The work in foundation and plinth shall include: (a) For buildings: All works upto 1.2 metre above ground level or upto floor 1 level whichever is lower: (b) For abutments, piers and well steining: all works upto 1.2 m above the bed level: (c) For retaining wall, wing walls, compound walls, chimneys, over head reservoirs/ tanks and other elevated structures: All works upto 1.2 metre above the ground level: (d) For reservoirs/ tanks (other than overhead reservoirs/ tanks): All works upto 1.2 metre above the ground level: (e) For basements: All works upto 1.2 m above ground level or upto floor 1 level whichever is lower. Note: Specific provision shall be made in the estimate for such situations where the foundation level is more than 3 (three) metre depth from the plinth for all types of structures mentioned above.

0.7 MEASUREMENTS 0.7.1 In booking dimensions, the order shall be consistent and in the sequence of length, width and height or depth or thickness. 0.7.2 Rounding off: Rounding off where required shall be done in accordance with IS: 2-1960. The number of significant places rounded in the rounded off value should be as specified. 0.8 MATERIALS 0.8.1 Samples of all materials to be used on the work shall be got approved by the contractor from the Engineer-in-Charge well in time. The approved samples duly authenticated and sealed shall be kept in the custody of the Engineer-in-Charge till the completion of the work. All materials to be provided by the contractor shall be brand new and as per the samples approved by the Engineer-in-Charge. 0.8.2 Materials obtained by the contractor from the sources approved by the Department shall be subjected to the Mandatory tests. Where such materials do not conform to the relevant specifications, the matter shall be taken up by the Engineer-in-Charge for appropriate action against the defaulters. In all such cases, necessary documents in original and proof of payment relating to the procurement of materials shall be made available by the contractor to the Engineer-in-Charge. 0.8.3 Samples, whether submitted for approval to govern bulk supplies or required for testing before use and also the sample of materials bearing ‘Standard mark,’ if required for testing, shall be provided free of cost by the contractor. All other incidental expenditure to be incurred for testing of samples e.g. packaging, sealing transportation, loading, unloading etc. except testing charges shall be borne by the contractor. 0.8.4 The materials, supplied by the Department shall be deemed to be complying with the specifications. 0.8.5 Materials stored at site, depending upon the individual characteristics, shall be protected from atmospheric effects due to rain, sun, wind and moisture to avoid deterioration. CPWD SPECIFICATIONS 2009

6

0.8.6 Materials like timber, paints etc. shall be stored in such a way that there may not be any possibility of fire hazards. Inflammable materials and explosives shall be stored in accordance with the relevant rules and regulations or as approved by Engineer-in-Charge in writing so as to ensure desired safety during storage. 0.8.7 The unit weight of materials unless otherwise specified shall be reckoned as given in IS: 1911-1967. 0.9 SAFETY IN CONSTRUCTION 0.9.1 The contractor shall employ only such methods of construction, tools and plant as are appropriate for the type of work or as approved by Engineer-in-Charge in writing. 0.9.2 The contractor shall take all precautions and measures to ensure safety of works and workman and shall be fully responsible for the same. Safety pertaining to construction works such as excavation, centering and shuttering, trenching, blasting, demolition, electric connections, scaffolds, ladders, working platforms, gangway, mixing of bituminous materials, electric and gas welding, use of hoisting and construction machinery shall be governed by CPWD safety code, relevant safety codes and the direction of Engineer-in-Charge 0.10 ABBREVIATIONS The following abbreviations wherever they appear in the specifications, shall have the meaning or implication hereby assigned to them: Mm Cm M Km Mm2/sqmm Cm2/sqcm Dm2/sqdm M2/sqm Cm3/ cubic cm Dm3/ cubic dm M3/cum Ml Kl Gm Kg Q T Fps system °C Fig Re/Rs No Dia AC CI GC GP GI PVC RCC SW SWG

Millimetre Centimetre Metre Kilometre Square Milimetre Square centimetre Square decimetre Square metre Cubic centimetre Cubic decimetre Cubic metre Millilitre Kilolitre Gram Kilogram Quintal Tonne Foot pound second system Degree Celsius temperature Figure Rupee/ Rupees Number Diameter Asbestos cement Cast Iron Galvanised corrugated Galvanised plain Galvanised iron Polyvenyl chloride Reinforced cement concrete Stone ware Standard wire Gauge 7

SUB HEAD 0.0 : GENERAL

CPWD SPECIFICATIONS 2009

8

SUB HEAD : 1.0

CARRIAGE OF MATERIALS

CONTENTS Clause No.

Brief Description List of Bureau of Indian Standard Codes

1.0

General

14

1.1

Responsibility for Loss or Damage

14

1.2

Mode of Carriage

14

1.3

Lead

14

1.4

General Consideration for Stacking and Storage

14

1.5

Protection against Atmospheric Agencies

14

1.6

Protection against fire and other Hazards

14

1.7 to 1.26

Stacking and Storage of Materials

1.27

Measurements

21

1.28

Rate

21

Table 1.1

Storage and Stacking Check List

22

Fig. 1.1

Typical Sketch for Cement Godown

23

11

Page No. 13

15-21

SUB HEAD 1.0 : CARRIAGE OF MATERIALS

CPWD SPECIFICATIONS 2009

12

LIST OF BUREAU OF INDIAN STANDARD CODES S. No.

I. S. No.

Subject

1.

IS 4082

Stacking & storage of construction materials and components at site – Recommendations

2.

IS 1141

Seasoning of Timber – Code of Practice

13

SUB HEAD 1.0 : CARRIAGE OF MATERIALS

1.0 CARRIAGE OF MATERIALS

1.0 GENERAL The carriage and stacking of materials shall be done as directed by the Engineer-in-Charge. Any tools and plants, required for the work shall be arranged by the Contractor. The carriage of materials includes loading within a lead of 50 metres, unloading and stacking within a lead of 50 metres. 1.1 RESPONSIBILITY FOR LOSS OR DAMAGE Loading, carriage, unloading and stacking shall be done carefully to avoid loss or damage to materials. In case of any loss or damage, recovery shall be effected from the Contractor at twice Departmental issue rates of the materials. If the departmental issue rates of the materials are available then the recovery shall be effected at twice the prevailing market rates as determined by Engineer-in-Charge.

the the not the

1.2 MODE OF CARRIAGE Depending upon the feasibility and economy, the Engineer-in-Charge shall determine the mode of carriage viz. whether by mechanical or animal transport or manual labour. 1.3 LEAD 1.3.1 All distances shall be measured over the shortest practical route and not necessarily the route actually taken. Route other than shortest practical route may be considered in cases of unavoidable circumstances and as approved by Engineer-in-Charge alongwith reasons in writing. 1.3.2 Carriage by manual labour shall be reckoned in units of 50 metres or part thereof. 1.3.3 Carriage by animal and mechanical transport shall be reckoned in one km unit. Distances of 0.5 km or more shall be taken as 1 km and distance of less than 0.5 km shall be ignored. However, when the total lead is less than 0.5 km, it will not be ignored but paid for separately in successive stages of 50 metres subject to the condition that the rate worked on this basis does not exceed the rate for initial lead of 1 km by mechanical/ animal transport. 1.4 GENERAL CONSIDERATION FOR STACKING AND STORAGE 1.4.1 Planning of Storage Layout For any site, there should be proper planning of the layout for stacking and storage of different materials, components and equipments with proper access and proper manoeuvrability of the vehicles carrying the material. While planning the layout, the requirements of various materials, components and equipments at different stages of construction shall be considered. The storage & stacking check list is given in Table 1.1. For further details refer IS- 4082. 1.4.2 Material shall be stored in such a manner as to prevent deterioration or intrusion of foreign matter and to ensure the preservation of their quality and fitness for the work. 1.5 PROTECTION AGAINST ATMOSPHERIC AGENCIES Materials stored at site, depending upon the individual characteristics, shall be protected from atmospheric actions, such as rain, sun, winds and moisture to avoid deterioration. 1.6 PROTECTION AGAINST FIRE AND OTHER HAZARDS 1.6.1 Materials like timber, coal, paints, etc. shall be stored in such a way that there may not be any possibility of fire hazards. Inflammable materials like kerosene and petrol, shall be stored in accordance with the relevant rules and regulations so as to ensure the desired safety during storage. Stacks shall CPWD SPECIFICATIONS 2009

14

not be piled so high as to make them unstable under fire fighting conditions and in general they shall not be more than 4.5 m in height. The provisions given in IS 13416 (part 5) shall be followed. 1.7 STACKING AND STORAGE OF MATERIALS 1.7.1 Cement 1.7.1.1 In case cement is received in bags. Cement shall be stored at the work site in a building or a shed which is dry, leakproof and as moisture proof as possible. The building or shed for storage should have minimum number of windows and close fitting doors and these should be kept closed as far as possible. 1.7.1.2 Cement shall be stored and stacked in bags and shall be kept free from the possibility of any dampness or moisture coming in contact with them. Cement bags shall be stacked off the floor on wooden planks in such a way as to keep about 150 mm to 200 mm clear above the floor. The floor may comprise of lean cement concrete or two layers of dry bricks laid on well consolidated earth. A space of 600 mm minimum shall be left alround between the exterior walls and the stacks (see Fig. 1.1) In the stacks the cement bags shall be kept close together to reduce circulation of air as much as possible. Owing to pressure on the bottom layer of bags sometimes ‘warehouse pack’ is developed in these bags. This can be removed easily by rolling the bags when the cement is taken out for use. Lumbed bags, if any should be removed and disposed off. 1.7.1.3 The height of stack shall not be more than 10 bags to prevent the possibility of lumping up under pressure. The width of the stack shall be not more than four bags length or 3 metres. In stacks more than 8 bags high, the cement bags shall be arranged alternately length-wise and cross-wise so as to tie the stacks together and minimize the danger of topping over. Cement bags shall be stacked in a manner to facilitate their removal and use in the order in which they are received; a lable showing date of receipt of cement shall be put on each stack to know the age of cement. 1.7.1.4 For extra safety during the monsoon, or when it is expected to store for an unusually long period, the stack shall be completely enclosed by a water proofing membrane such as polyethylene, which shall close on the top of the stack. Care shall be taken to see that the waterproofing membrane is not damaged any time during use. 1.7.1.5 Cement in gunny bags, paper bags and polyethylene bags shall be stored separately. 1.7.2 In case cement is received in drums These shall be stored on plane level ground, as far as possible near the concrete mixing place. After taking out the required quantity of cement, the lid of the drum shall be securely tied to prevent ingress of moisture. 1.7.3 In case cement is received in silos The silos shall be placed near the concrete batching plant. Proper access shall be provided for the replacement of silos. 1.7.4 Different types of cements shall be stacked and stored separately. 1.8 BRICKS 1.8.1 Bricks shall be stacked in regular tiers as and when they are unloaded to minimize breakage and defacement. These shall not be dumped at site. 1.8.2 Bricks stacks shall be placed close to the site of work so that least effort is required to unload and transport the bricks again by loading on pallets or in barrows. Building bricks shall be loaded or

15

SUB HEAD 1.0 : CARRIAGE OF MATERIALS

unloaded a pair at a time unless palletized. Unloading of building bricks or handling in any other way likely to damage the corners or edges or other parts of bricks shall not be permitted. 1.8.3 Bricks shall be stacked on dry firm ground. For proper inspection of quality and ease in counting the stacks shall be 50 bricks long, 10 bricks high and not more than 4 bricks in width, the bricks being placed on edge, two at a time along the width of the stack. Clear distance between adjacent stacks shall not be less than 0.8 m. Bricks of each truck load shall be put in one stack. 1.8.4 Bricks of different types, such as clay bricks, clay fly ash bricks, fly ash lime bricks, sand lime (calcium silicate) bricks, auto-clave bricks etc. shall be stacked separately. Bricks of different classification and size consideration (such as, conventional and modular) shall be stacked separately. Also bricks of different types, such as, solid, hollow and perforated shall be stacked separately. 1.9 BLOCKS 1.9.1 Blocks are available as hollow and solid concrete blocks, hollow and solid light weight concrete blocks, autoclaved aerated concrete blocks, concrete stone masonry blocks and soil based blocks. 1.9.2 Blocks shall be unloaded one at a time and stacked in regular tiers to minimize breakage and defacement. These shall not be dumped at site. The height of the stack shall not be more than 1.2 m. The length of the stack shall not be more than 3.0 m, as far as possible and the width shall be of two or three blocks. 1.9.3 Normally blocks cured for 28 days only should be received at site. In case blocks cured for less than 28 days are received, these shall be stacked separately. All blocks should be water cured for 10 to 14 days and air cured for another 15 days; thus no blocks with less than 28 days curing shall be used in building construction. 1.9.4 Blocks shall be placed close to the site of work so that least effort is required for their transportation. 1.9.5 Blocks manufactured at site shall be stacked at least for required minimum curing period as given in 1.9.3. 1.9.6 The date of manufacture of the blocks shall be suitably marked on the stacks of blocks manufactured at factory or site. 1.10 FLOOR, WALL AND ROOF TILES 1.10.1 Floor, wall and clay roof tiles of different types, such as, cement concrete tiles (plain, coloured and terrazzo) and ceramic tiles (glazed and unglazed) shall be stacked on regular platform as far as possible under cover in proper layers and in tiers and they shall not be dumped in heaps. In the stack, the tiles shall be so placed that the mould surface of one faces that of another. Height of the stack shall not be more than one metre. During unloading, these shall be handled carefully so as to avoid breakage. 1.10.2 Tiles of different quality, size and thickness shall be stacked separately to facilitate easy removal for use in work. Tiles when supplied by manufacturers packed in wooden crates, shall be stored in crates. The crates shall be opened one at a time as and when required for use. 1.10.3 Ceramic tiles and clay roof tiles are generally supplied in cartons which shall be handled with care. It is preferable to transport these at the site on platform trolleys. 1.11 AGGREGATES 1.11.1 Aggregates shall be stored at site on a hard dry and level patch of ground. If such a surface is not available, a platform of planks or old corrugated iron sheets, or a floor of bricks, or a thin layer of CPWD SPECIFICATIONS 2009

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lean concrete shall be made so as to prevent contamination with clay, dust, vegetable and other foreign matter. 1.11.2 Stacks of fine and coarse aggregates shall be kept in separate stock piles sufficiently removed from each other to prevent the material at the edges of the piles from getting intermixed. On a large job, it is desirable to construct dividing walls to give each type of aggregates its own compartment. Fine aggregates shall be stacked in a place where loss due to the effect of wind is minimum. 1.11.3 Unless specified otherwise or necessitated by site conditions stacking of the aggregates should be carried out in regular stacks. The suggested sizes for stacks are as follows : Sl. no.

Material

(i)

Soling stone

(ii)

Coarse aggregates

Size of Stack (in m)

Or Or Or (iii)

Fine aggregates Or Or

Length 5.0 5.0 2.0 5.0 5.0 2.0 5.0 5.0

Breadth 2.0 1.0 2.0 5.0 1.0 2.0 5.0 1.0

Height 0.50 0.50 0.50 1.00 0.50 0.50 1.00 0.50

1.12 FLY ASH Fly ash shall be stored in such a manner as to permit easy access for proper inspection and identification of each consignment. Fly ash in bulk quantities shall be stored in stack similar to fine aggregates as specified in 1.11 to avoid any intrusion of foreign matter. Fly ash in bags shall be stored in stacks not more than 10 bags high. 1.13 STEEL 1.13.1 For each classification of steel, separate areas shall be earmarked. It is desirable that ends of bars and sections of each class be painted in distinct separate colours. 1.13.2 Steel reinforcement shall ordinarily be stored in such a way as to avoid distortion and to prevent deterioration and corrosion. It is desirable to coat reinforcement with cement wash before stacking to prevent scaling and rusting. 1.13.3 Bars of different classification, sizes and lengths shall be stored separately to facilitate issues in such sizes and lengths so as to minimize wastage in cutting from standard lengths. 1.13.4 In case of long storage, reinforcement bars shall be stacked above ground level by at lest 150 mm. Also in coastal areas or in case of long storage a coat of cement wash shall be given to prevent scaling and rusting. 1.13.5 Structural steel of different classification, sizes and lengths shall be stored separately. It shall be stored above ground level by at least 150 mm upon platforms, skids or any other suitable supports to avoid distortion of sections. In coastal areas or in case of long storage suitable protective coating of primer paint shall be given to prevent scaling and rusting. 1.14 ALUMINIUM SECTIONS Aluminium sections of different classification, sizes and lengths shall be stored separately, on a level platform under cover. The aluminium sections shall not be pulled or pushed from the stack nor shall be slided over each other, to protect the anodizing layer. 17

SUB HEAD 1.0 : CARRIAGE OF MATERIALS

1.15 DOORS, WINDOWS AND VENTILATORS 1.15.1 General While unloading, shifting handling and stacking timber or other lignocellulosic material based, metal and plastic door and window frames and shutters, care shall be taken that the material is not dragged one over the other as it may cause damage to the surface of the material particularly in the case of decorative shutters. The material should be lifted and carried preferably flat avoiding damage of corners or sides. 1.15.2 Metal and plastic doors, windows and ventilators shall be stacked upright (on their sills) on level ground preferably on wooden battens and shall not come in contact with dirt and ashes. If received in crates they shall be stacked according to manufacturer’s instructions and removed from the crates as and when required for the work. 1.15.3 Metal and plastic frames of doors, windows and ventilators shall be stacked upside down with the kick plates at the top. These shall not be allowed to stand for long in this manner before being fixed so as to avoid the door frames getting out of shape and hinges being strained and shutters drooping. 1.15.4 During the period of storage all metal doors, windows and ventilators shall be protected from loose cement and mortar by suitable covering such as tarpauline. The tarpauline shall be hung loosely on temporary framing to permit circulation of air to prevent condensation. 1.15.5 All timber and other lignocellulosic material based frames and shutters shall be stored in a dry and clean covered space away from any infestation and dampness. The storage shall preferably be in well ventilated dry rooms. The frames shall be stacked one over the other in vertical stacks with cross battens at regular distances to keep the stack vertical and straight. These cross battens should be of uniform thickness and placed vertically one above the other. The door shutters shall be stacked in the form of clean vertical stacks over the other and at least 80 mm above ground on pallets or suitable beams or rafters. The top of the stack shall be covered by a protecting cover and weighted down by means of scantlings or other suitable weights. The shutter stack shall rest on hard and level ground. 1.15.6 If any timber or other lignocellulosic material based frame or shutter becomes wet during transit, it shall be kept separate from the undamaged material. The wet material may be dried by stacking in shade with battens in between adjacent boards with free access of dry air generally following the guidance laid down in IS 1141. 1.15.7 Separate stacks shall be built up for each size, each grade and each type of material. When materials of different sizes grades and types are to be stacked in one stack due to shortage of space, the bigger size shall be stacked in the lower portion of the stacks. Suitable pallets or separating battens shall be kept in between the two types of material. 1.16 ROOFING SHEETS 1.16.1 Roofing sheets shall be stored and handled in such a manner as not do damage them in any way. 1.16.1 Plain and corrugated asbestos cement sheets shall be stacked horizontally to a height of not more than one meter on a firm and level ground, with timber or other packing beneath them. If stacked in exposed position, they shall be protected from damage by the winds. Asbestos cement sheets of same variety and size shall be stacked together. Damage sheets shall not be stacked with sound materials. All damaged sheets shall be salvaged as early as possible.

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1.16.2 Corrugated galvanized iron sheets and aluminium sheets shall be stacked horizontally to a height of not more than 0.5 m on a firm and level ground, with timber or other packing beneath them. To protect them from dust and rain water, these shall be covered with tarpaulin or polyethylene sheets. 1.16.3 Plastic sheets and glass reinforced plastic (GRP) sheets shall be stacked under a shed to a height of not more than 0.5 m on a firm and level ground with timber or other packing beneath them. 1.17 GYPSUM BOARDS, PLYWOOD, FIBREBOARD, PARTICLE BOARD, BLOCK BOARD, ETC. 1.17.1 These boards shall be stored flat in a covered clean and dry place. Different sizes and types of each of these boards shall be stacked separately. The board shall be stacked on a flat platform on which a wooden frame shall be constructed with 50 mm x 25 mm battens in such a way that it will give support to all four edges and corners of the boards with intermediate battens placed at suitable intervals to avoid warping. The boards shall be stacked in a solid block in a clear vertical alignment. The top sheet of each stack shall be suitably weighed down to prevent warping wherever necessary. The boards shall be unloaded and stacked with utmost care avoiding damage to the corners and surface. In case of decorative plywood and decorative boards, the surfaces of which are likely to get damaged by dragging one sheet over another it is advisable that these are lifted as far as possible in pairs facing each other. 1.18 GLASS SHEETS 1.18.1 It is important that all glass sheets whether stored in crates or not shall be kept dry. Suitable covered storage space shall be provided for the safe storage of the glass sheets. In removing glass sheets from crates, great care shall be taken to avoid damages. The glass sheets shall be lifted and stored on its long edges against a vertical wall or other support with the first sheet so placed that its bottom edge is 25 mm from the vertical support. The stacks shall be of not more than 25 panes and shall be supported at two points by fillets of wood at 300 mm from each end. The whole stack shall be as close and as upright as possible. The glass sheets of different sizes, thickness and type shall be stacked separately. The distance between any two stacks shall be of the order of 400 mm. 1.19 CAST IRON, GALVANIZED IRON AND ASBESTOS CEMENT PIPES AND FITTINGS 1.19.1 The pipes shall be unloaded where they are required when the trenches are ready to receive them. 1.19.2 Storage shall be done on firm, level and clear ground and wedges shall be provided at the bottom layer to keep the stack stable. 1.19.3 The stack shall be in pyramid shape or the pipes length-wise and cross-wise in alternate layers. The pyramid stack is advisable in smaller diameter pipes for conserving space in storing them. The height of the stack shall not exceed 1.5 m. 1.19.4 Each stack shall contain only pipes of same class and size, with consignment or batch number marked on it with particulars of suppliers wherever possible. 1.19.5 Cast iron detachable joints and fittings shall be stacked under cover separately from the asbestos cement pipes and fittings.

19

SUB HEAD 1.0 : CARRIAGE OF MATERIALS

1.19.6 Rubber rings shall be kept clean, away from grease, oil heat and light. 1.20 POLYETHYLENE PIPES 1.20.1 Natural polyethylene pipe should be stored under cover and protected from direct sunlight. However, black polyethylene pipes may be stored either under cover or in the open. 1.20.2 Coils may be stored either on edges or stacked flat one on top of the other, but in either case they should not be allowed to come into contact with hot water or steam pipes and should be kept away from hot surface. 1.20.3 Straight lengths should be stored on horizontal racks giving continuous support to prevent the pipe taking on a permanent set. 1.20.4 Storage of pipes in heated areas exceeding 27o C should be avoided. 1.21 UNPLASTICIZED PVC PIPES 1.21.1 The pipe should be given adequate support at all times. Pipes should be stored on a reasonably flat surface free from stones and sharp projections so that the pipe is supported throughout its length. In storage, pipe racks should be avoided. Pipe should not be stacked in large piles, especially under warm temperature conditions as the bottom pipes may distort, thus giving rise to difficulty in jointing. Socket and spigot pipes should be stacked in layers with sockets placed at alternate ends of the stacks to avoid lopsided stacks. 1.21.1.1 It is recommended not to store pipe inside another pipe. 1.21.1.2 On no account should pipes be stored in a stressed or bent condition or near the sources of heat. 1.21.1.3 Pipes should not be stacked more than 1.5 m high. Pipes of different sizes and classes should be stacked separately. 1.21.2 The ends of pipe should be protected from abrasion particularly those specially prepared for jointing either spigot or socket solvent welded joints or shouldered for use with couplings. 1.21.3 In tropical conditions, pipes should be stored in shade. In very cold weather, the impact strength of PVC is reduced making it brittle and more care in handling shall be exercised in wintry condition. 1.21.4 If due to unsatisfactory storage of handling a pipe becomes kinked, the damaged portion should be cut out completely. Kinking is likely to occur only on very thin walled pipes. 1.22 BITUMEN, ROAD TAR, ASPHALT, ETC. 1.22.1 All types of bitumen, road tar, asphalt, etc, in drums or containers shall be stacked vertically on their bottoms in up to 3 tiers. Leaky drums shall be segregated. Empty drums shall be stored in pyramidal stacks neatly in rows. 1.23 WATER 1.23.1 Wherever water is to be stored for construction purposes this shall be done in proper storage tanks to prevent any organic impurities getting mixed up with it. 1.24 OIL PAINTS 1.24.1 All containers of paints, thinners and allied materials shall preferably be stored in a separate room on floors with sand cushions. The room shall be well-ventilated and free from excessive heat, sparks of flame and direct rays of sun. The containers of paint shall be kept covered or properly fitted CPWD SPECIFICATIONS 2009

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with lid and shall not be kept open except while using. The containers of paints have expiry date marked by the manufacturers, which should be highlighted so as to facilitate use of paint within due period. 1.25 SANITARY APPLIANCES 1.25.1 All sanitary appliances shall be carefully stored under cover to prevent damage. When accepting and storing appliances, advance planning shall be made regarding the sequence of removal from the store to the assembly positions. Supporting brackets shall be so stored as to be readily accessible for use with the appliances. 1.26 OTHER MATERIALS 1.26.1 Small articles like nails, screws, nuts and bolts, door and window fittings, polishing stones, protective clothing, spare parts of machinery, linings, packing, water supply and sanitary fittings, electrical fittings, insulation board, etc, shall be kept in suitable and properly protected store rooms. Valuable small material such as, copper pipes and fittings shall be kept under lock and key. 1.27 MEASUREMENTS Length, breadth and height of stacks shall be measured correct to a cm. The quantity shall be worked out in cubic metre correct to two place of decimal. The volume of stacks shall be reduced by percentages as shown against each for looseness in stacking to arrive at the net quantity for payment . No reduction shall be made in respect of articles or materials for which mode of payment is by length or weight or number. 1.27.1 Earth 1.27.1.1 In loose stacks such as cart loads, lorry loads, etc. – 20% 1.27.1.2 In fills consolidated by light mechanical machinery – 10% 1.27.1.3 In fills consolidated by heavy mechanical machinery but not under OMC (Optimum Moisture Content) – 5% 1.27.1.4 In fills consolidated by heavy mechanical machinery at OMC – Nil 1.27.1.5 Consolidated fills in confined situation such as under floors. etc. – Nil 1.27.2 Other Materials 1.27.2.1 Manure or sludge – 8% 1.27.2.2 Moorum, building rubbish Lime and sand – Nil 1.27.2.3 Stone metal, 40 mm nominal size and above – 7.5% 1.27.2.4 Coarse aggregate/ stone metal below 40 mm nominal size – Nil 1.27.2.5 Soling stone/ Boulder 100 mm and above – 15% 1.27.2.6 Excavated rocks – 50% 1.28 RATE The rate for carriage of materials is inclusive of all the operations described above.

21

SUB HEAD 1.0 : CARRIAGE OF MATERIALS

TABLE 1.1 Storage and Stacking Check List (Clause 1.4.1) Sl. No.

Material/ Component

1. 2.

Cement Stone and Aggregates Stones, aggregates, fly ash and cinder Veneering stones Bricks and Blocks Tiles Clay and concrete floor, wall and roof tiles Ceramic tiles Steel Aluminum Sections Door, windows and Ventilators Roofing Sheets AC GI and Aluminum Sheets Plastic Sheets Boards like Plywood, Particle Boards, Fibre Boards, Blockboards and Gypsum Board Glass Sheets CI, GI and AC Pipes & fittings Pipes CI and GI fittings AC Fittings Polyethlylene Pipes Unplasticized PVC Pipes Bitumen, Road Tar, Asphalt, etc in Drums Oil Paints Sanitary Appliances

(a)

(b) 3. 4. (a)

(b) 5. 6. 7. 8. (a) (b) (c) 9.

10. 11. (a) (b) (c) 12. 13. 14.

15. 16.

Firm Level Ground

CPWD SPECIFICATIONS 2009

Base Hard Floor

Off Floor

Heaps

√ √

Stack Tiers Flat

Vertical

Open

√ √



√ √

√ √











√ √ √





Type of Cover Open Under but shed covered √

√ √





√ √

√ √ √

√ √ √ √

√ √

√ √

√ √

√ √



√ √ √ √ √







√ √



√ √ √ √













√ √ √





22





√ √

√ √

√ √

TYPICAL SKETCH FOR CEMENT GODOWN Sub Head : Carriage Clause : 1.7.1.2

A.C. or G.I. SHEET OR ANY KIND OF WEATHER PROOF ROOF

1400

2400

LOAD BEARING WALL

MAX 10 BAGS A B C

G.L.

D

P

A

S

S

A

G

E

SECTION

600

1400

600

1400

600

DOOR PLAN

A = Planks B = Wooden Battens C = 150 Dry Bricks in two Layers or Lean Cement Concrete D = 150 Consolidated Earth Drawing not to scale All Dimensions in millimetres

Fig. 1.1 : Typical Arrangement in Cement Godown

23

SUB HEAD 1.0 : CARRIAGE OF MATERIALS

CPWD SPECIFICATIONS 2009

24

SUB HEAD : 2.0

EARTH WORK

CONTENTS Clause No.

Brief Description List of Bureau of Indian Standard Codes

2.0

Definitions

30

2.1

Classification of Soils

30

2.2

Antiquities and Useful Materials

31

2.3

Protections

31

2.4

Site Clearance

31

2.5

Setting out and Making profiles

32

2.6

Blasting

32

2.7

Excavation in All kinds of soils

34

2.8

Excavation in Ordinary/ Hard rock

35

2.9

Earth work by mechanical means

36

2.10

Filling

38

2.11

Measurements

38

2.12

Rates

40

2.13

Surface Excavation

40

2.14

Rough Excavation and Filling

41

2.15

Excavation over Area (All kinds of Soil)

41

2.16

Excavation over Area (Ordinary/Hard rock)

41

2.17

Excavation in Trenches for Foundations and Drains (All kinds of Soil)

41

2.18

Excavation in Trenches for Foundation and Drains (Ordinary/ Hard rock)

41

2.19

Excavation in Trenches for Pipes, Cables etc. and Refilling

42

2.20

Planking and Strutting

43

2.21

Excavation in Water, Mud or Foul position

44

27

Page No. 29

SUB HEAD 2.0 : EARTH WORK

2.22

Earth work for major works

45

2.23

Filling in Trenches, Plinth, under Floor etc.

46

2.24

Sand Filling in Plinth

47

2.25

Surface Dressing

47

2.26

Jungle Clearance

47

2.27

Felling Trees

48

2.28

Anti Termite Treatment

49

Fig. 2.1

The Design for Temporary Site Bench Mark

54

Fig. 2.2

Close and Open Planking and Strutting

55

Fig. 2.3 (i to viii)

Anti-Termite Construction Stage 1 to 8

56

Fig. 2.4

Anti-Termite Construction – Final Recommendations

60

CPWD SPECIFICATIONS 2009

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LIST OF BUREAU OF INDIAN STANDARD CODES S. No. 1 2 3

I.S. No. IS 632 IS 1200 (Pt 1) IS 1200 (Pt-27)

4 5 6 7 8 9 10 11

IS 4081 IS 4988 (Part IV) IS 6313 (pt-II) IS 6313(pt.-III) IS 6940 IS 8944 IS 8963 IS 12138

Subject Gamma – BHC (Lindane) emulsifiable concentrates Method of measurement of earth work Method of measurement of earth work (by Mechanical Appliances ) Safety code for Blasting and related drilling operation Excavators Anti Termite measures in buildings (pre -constructional) Anti Termite Measures in Buildings for existing buildings Methods of test for pesticides and their formulations Chlorpyrifos emulsifiable concentrates Chlorpyrifos – Technical specifications Earth moving Equipments

29

SUB HEAD 2.0 : EARTH WORK

2.0 EARTH WORK 2.0 DEFINITIONS Deadmen or Tell Tales: Mounds of earth left undisturbed in pits dug out for borrowing earth Burjis: Short pillars of brick/ stone having top surface finished with cement plaster for marking etc. Formation or Profile: Final shape of the ground after excavation or filling up. Foul condition: Filthy and unhygienic conditions where physical movements are hampered such as soil mixed with sewage or night soil. Lead : All distances shall be measured over the shortest practical route and not necessarily the route actually taken. Route other than shortest practical route may be considered in cases of unavoidable circumstances and approved by Engineer-in-charge along with reasons in writing. Carriage by manual labour shall be reckoned in units of 50 metres or part thereof. Carriage by animal and mechanical transport shall be reckoned in one km. unit. Distances of 0.5 km. or more shall be taken as 1 km. and distance of less than 0.5 km. shall be ignored. However, when the total lead is less than 0.5 km., it will not be ignored but paid for separately in successive stages of 50 metres subject to the condition that the rate worked on this basis does not exceed the rate for initial lead of 1 km. by mechanical/animal transport. Lift: The vertical distance for removal with reference to the ground level. The excavation up to 1.5 metres depth below the ground level and depositing the excavated materials upto 1.5 metres above the ground level are included in the rate of earth work. Lifts inherent in the lead due to ground slope shall not be paid for. Safety rules: Safety rules as laid down by the statutory authority and as provided in National Building Code (NBC) shall be followed. 2.1 CLASSIFICATION OF SOILS 2.1.0 The earthwork shall be classified under the following categories and measured separately for each category: (a) All kind of soils: Generally any strata, such as sand, gravel, loam, clay, mud, black cotton moorum, shingle, river or nallah bed boulders, siding of roads, paths etc. and hard core, macadam surface of any description (water bound, grouted tarmac etc.), lime concrete mud concrete and their mixtures which for excavation yields to application of picks, showels, jumper, sacrifiers, ripper and other manual digging implements. (b) Ordinary rock: Generally any rock which can be excavated by splitting with crow bars or picks and does not require blasting, wedging or similar means for excavation such as lime stone, sand stone, hard laterite, hard conglomerate and un-reinforced cement concrete below ground level. If required light blasting may be resorted to for loosening the materials but this will not in any way entitle the material to be classified as ‘Hard rock’. (c) Hard rock: Generally any rock or boulder for the excavation of which blasting is required such as quartzite, granite, basalt, reinforced cement concrete (reinforcement to be cut through but not separated from concrete) below ground level and the like.

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(d) Hard rock (blasting prohibited): Hard rock requiring blasting as described under (c) but where the blasting is prohibited for any reason and excavation has to be carried out by chiseling, wedging, use of rock hammers and cutters or any other agreed method. 2.2 ANTIQUITIES AND USEFUL MATERIALS 2.2.1 Any finds of archaeological interest such as relics of antiquity, coins, fossils or other articles of value shall be delivered to the Engineer-in-Charge and shall be the property of the Government. 2.2.2 Any material obtained from the excavation which in the opinion of the Engineer-in-Charge is useful shall be stacked separately in regular stacks as directed by the Engineer-in-Charge and shall be the property of the Government. 2.3 PROTECTIONS 2.3.1 Excavation where directed by the Engineer-in-Charge shall be securely barricaded and provided with proper caution signs, conspicuously displayed during the day and properly illuminated with red lights and/or written using fluorescent reflective paint as directed by engineer in charge during the night to avoid accident. 2.3.2 The Contractor shall take adequate protective measures to see that the excavation operations do not damage the adjoining structures or dislocate the services. Water supply pipes, sluice valve chambers, sewerage pipes, manholes, drainage pipes and chambers, communication cables, power supply cables etc. met within the course of excavation shall be properly supported and adequately protected, so that these services remain functional. However, if any service is damaged during excavation shall be restored in reasonable time. 2.3.3 Excavation shall not be carried out below the foundation level of the adjacent buildings until underpinning, shoring etc. is done as per the directions of the Engineer-in-Charge for which payment shall be made separately.

2.3.4 Any damages done by the contractor to any existing work shall be made good by him at his own cost. Existing drains pipes, culverts, over head wires, water supply lines and similar services encountered during the course of execution shall be protected against damage by the contractor. The contractor shall not store material or otherwise occupy any part of the site in manner likely to hinder the operations of such services. 2.4 SITE CLEARANCE 2.4.1 Before the earth work is started, the area coming under cutting and filling shall be cleared of shrubs, rank vegetation, grass, brushwood, trees and saplings of girth up to 30cm measured at a height of one metre above ground level and rubbish removed up to a distance of 50 metres outside the periphery of the area under clearance. The roots of trees and saplings shall be removed to a depth of 60cm below ground level or 30 cm below formation level or 15 cm below sub grade level, whichever is lower, and the holes or hollows filled up with the earth, rammed and leveled. 2.4.2 The trees of girth above 30 cm measured at a height of one metre above ground shall be cut only after permission of the Engineer-in-Charge is obtained in writing. The roots of trees shall also be removed as specified in 2.4.1. payment for cutting such trees and removing the roots shall be made separately. 2.4.3 Existing structures and services such as old buildings, culverts, fencing, water supply pipe lines, sewers, power cables, communication cables, drainage pipes etc. within or adjacent to the area if required to be diverted/removed, shall be diverted/dismantled as per directions of the Engineer-inCharge and payment for such diversion/dismantling works shall be made separately. 31

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2.4.4 In case of archaeological monuments within or adjacent to the area, the contractor shall provide necessary fencing alround such monuments as per the directions of the Engineer-in-Charge and protect the same properly during execution of works. Payment for providing fencing shall be made separately. 2.4.5 Lead of 50 m mentioned in the ‘Schedule Of Quantities’ is the average lead for the disposal of excavated earth within the site of work. The actual lead for the lead for the disposal of earth may be more or less than the 50 m for which no cost adjustment shall be made in the rates. 2.4.6 Disposal of Earth shall be disposed off at the specified location or as decided by the Engineer-inCharge. The contractor has to take written permission about place of disposal of earth before the earth is disposed off, from Engineer-in-Charge. 2.5 SETTING OUT AND MAKING PROFILES 2.5.1 A masonry pillar to serve as a bench mark will be erected at a suitable point in the area, which is visible from the largest area. This bench mark shall be constructed as per Fig. 2.1 and connected with the standard bench mark as approved by the Engineer-in-Charge. Necessary profiles with strings stretched on pegs, bamboos or ‘Burjis’ shall be made to indicate the correct formation levels before the work is started. The contractor shall supply labour and material for constructing bench mark, setting out and making profiles and connecting bench mark with the standard bench mark at his own cost. The pegs, bamboos or ‘Burjis’ and the bench mark shall be maintained by the contractor at his own cost during the excavation to check the profiles. 2.5.2 The ground levels shall be taken at 5 to 15 metres intervals (as directed by the Engineer-inCharge) in uniformly sloping ground and at closer intervals where local mounds, pits or undulations are met with. The ground levels shall be recorded in field books and plotted on plans. The plans shall be drawn to a scale of 5 metres to one cm or any other suitable scale decided by the Engineer-in-Charge. North direction line and position of bench mark shall invariable be shown on the plans. These plans shall be signed by the contractor and the Engineer-in-Charge or their authorized representatives before the earth work is started. The labour required for taking levels shall be supplied by the contractor at his own cost. 2.6 BLASTING 2.6.0 Where hard rock is met with and blasting operations are considered necessary, the contractor shall obtain the approval of the Engineer-in-Charge in writing for resorting to blasting operation. Note: In ordinary rock blasting operations shall not be generally adopted. However, the contractor may resort to blasting with the permission of the Engineer-in-charge, but nothing extra shall be paid for such blasting operations. The contractor shall obtain license from the competent authority for undertaking blasting work as well as for obtaining and storing the explosive as per the Explosive Act, 1884 as amended up to date and the Explosive Rules, 1983. The contractor shall purchase the explosives fuses, detonators, etc. only from a licensed dealer. The contractor shall be responsible for the safe transportation, storage and custody as per explosive rules and proper accounting of the explosive materials. Fuses and detonators shall be stored separately and away from the explosives. The Engineer-in-Charge or his authorized representative shall have the right to check the contractor’s store and account of explosives. The contractor shall provide necessary facilities for this. The contractor shall be responsible for any damage arising out of accident to workmen, public or property due to storage, transportation and use of explosive during blasting operation. 2.6.1 Blasting operations shall be carried out under the supervision of a responsible authorized agent of the contractor (referred subsequently as agent only), during specified hours as approved in writing by CPWD SPECIFICATIONS 2009

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the Engineer-in-Charge. The agent shall be conversant with the rules of blasting. In case of blasting with dynamite or any other high explosive, the position of all the bore holes to be drilled shall be marked in circles with white paint. These shall be inspected by the contractor’s agent. Bore holes shall be of a size that the cartridge can easily pass down. After the drilling operation, the agent shall inspect the holes to ensure that drilling has been done only at the marked locations and no extra hole has been drilled. The agent shall then prepare the necessary charge separately for each bore hole. The bore holes shall be thoroughly cleaned before a cartridge is inserted. Only cylindrical wooden tamping rods shall be used for tamping. Metal rods or rods having pointed ends shall never be used for tamping. One cartridge shall be placed in the bore hole and gently pressed but not rammed down. Other cartridges shall then be added as may be required to make up the necessary charge for the bore hole. The top most cartridge shall be connected to the detonator which shall in turn be connected to the safety fuses of required length. All fuses shall be cut to the length required before being inserted into the holes. Joints in fuses shall be avoided. Where joints are unavoidable a semi-circular nitch shall be cut in one piece of fuse about 2 cm deep from the end and the end of other piece inserted into the nitch. The two pieces shall then be wrapped together with string. All joints exposed to dampness shall be wrapped with rubber tape. The maximum of eight bore holes shall be loaded and fired at one occasion. The charges shall be fired successively and not simultaneously. Immediately before firing, warning shall be given and the agent shall see that all persons have retired to a place of safety. The safety fuses of the charged holes shall be ignited in the presence of the agent, who shall see that all the fuses are properly ignited. Careful count shall be kept by the agent and others of each blast as it explodes. In case all the charged bore holes have exploded, the agent shall inspect the site soon after the blast but in case of misfire the agent shall inspect the site after half an hour and mark red crosses (X) over the holes which have not exploded. During this interval of half an hour, nobody shall approach the misfired holes. No driller shall work near such bore until either of the following operations have been done by the agent for the misfired boreholes. (a) The contractor’s agent shall very carefully (when the tamping is of damp clay) extract the tamping with a wooden scraper and withdraw the fuse, primer and detonator. After this a fresh detonator, primer and fuse shall be placed in the misfired holes and fired, or (b) The holes shall be cleaned for 30 cm of tamping and its direction ascertained by placing a stick in the hole. Another hole shall then be drilled 15 cm away and parallel to it. This hole shall be charged and fired. The misfired holes shall also explode along with the new one. Before leaving the site of work, the agent of one shift shall inform the another agent relieving him for the next shift, of any case of misfire and each such location shall be jointly inspected and the action to be taken in the matter shall be explained to the relieving agent. The Engineer-in-Charge shall also be informed by the agent of all cases of misfires, their causes and steps taken in that connection. 2.6.2 General Precautions For the safety of persons red flags shall be prominently displayed around the area where blasting operations are to be carried out. All the workers at site, except those who actually ignite the fuse, shall withdraw to a safe distance of at least 200 metres from the blasting site. Audio warning by blowing whistle shall be given before igniting the fuse. Blasting work shall be done under careful supervision and trained personnel shall be employed. Blasting shall not be done with in 200 metres of an existing structure, unless specifically permitted by the Engineer-in-Charge in writing.

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All procedures and safety precautions for the use of explosives drilling and loading of explosives drilling and loading of explosives before and after shot firing and disposal of explosives shall be taken by the contractor as detailed in IS 4081, safety code for blasting and related drilling operation. 2.6.3 Precautions against Misfire The safety fuse shall be cut in an oblique direction with a knife. All saw dust shall be cleared from inside of the detonator. This can be done by blowing down the detonator and tapping the open end. No tools shall be inserted into the detonator for this purpose. If there is water present or if the bore hole is damp, the junction of the fuse and detonator shall be made water tight by means of tough grease or any other suitable material. The detonator shall be inserted into the cartridge so that about one third of the copper tube is left exposed outside the explosive. The safety fuse just above the detonator shall be securely tied in position in the cartridge. Water proof fuse only shall be used in the damp bore hole or when water is present in the bore hole. If a misfire has been found to be due to defective fuse, detonator or dynamite, the entire consignment from which the fuse detonator or dynamite was taken shall be got inspected by the Engineer-in-Charge or his authorized representative before resuming the blasting or returning the consignment. 2.7 EXCAVATION IN ALL KINDS OF SOILS 2.7.1 All excavation operations manually or by mechanical means shall include excavation and ‘getting out’ the excavated materials. In case of excavation for trenches, basements, water tanks etc. ‘getting out’ shall include throwing the excavated materials at a distance of at least one metre or half the depth of excavation, whichever is more, clear off the edge of excavation. In all other cases ‘getting out’ shall include depositing the excavated materials as specified. The subsequent disposal of the excavated material shall be either stated as a separate item or included with the items of excavation stating lead. 2.7.2 During the excavation the natural drainage of the area shall be maintained. Excavation shall be done from top to bottom. Undermining or undercutting shall not be done. 2.7.3 In firm soils, the sides of the trenches shall be kept vertical upto a depth of 2 metres from the bottom. For greater depths, the excavation profiles shall be widened by allowing steps of 50 cms on either side after every 2 metres from the bottom. Alternatively, the excavation can be done so as to give slope of 1:4 (1 horizontal : 4 vertical). Where the soil is soft, loose or slushy, the width of steps shall be suitably increased or sides sloped or the soil shored up as directed by the Engineer-inCharge. It shall be the responsibility of the contractor to take complete instructions in writing from the Engineer-in-Charge regarding the stepping , sloping or shoring to be done for excavation deeper than 2 metres. 2.7.4 The excavation shall be done true to levels, slope, shape and pattern indicated by the Engineer-inCharge. Only the excavation shown on the drawings with additional allowances for centering and shuttering or as required by the Engineer-in-Charge shall be measured and recorded for payment. 2.7.5 In case of excavation for foundation in trenches or over areas, the bed of excavation shall be to the correct level or slope and consolidated by watering and ramming. If the excavation for foundation is done to a depth greater than that shown in the drawings or as required by the Engineer-in-Charge, the excess depth shall be made good by the contractor at his own cost with the concrete of the mix used for levelling/ bed concrete for foundations. Soft/defective spots at the bed of the foundations shall be dug out and filled with concrete (to be paid separately) as directed by the Engineer-in-Charge. CPWD SPECIFICATIONS 2009

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2.7.6 While carrying out the excavation for drain work care shall be taken to cut the side and bottom to the required shape, slope and gradient. The surface shall then be properly dressed. If the excavation is done to a depth greater than that shown on the drawing or as required by the Engineer-in-Charge, the excess depth shall be made good by the contractor at his own cost with stiff clay puddle at places where the drains are required to be pitched and with ordinary earth, properly watered and rammed, where the drains are not required to be pitched. In case the drain is required is to be pitched, the back filling with clay puddle, if required, shall be done simultaneously as the pitching work proceeds. The brick pitched storm water drains should be avoided as far as possible in filled-up areas and loose soils. 2.7.7 In all other cases where the excavation is taken deeper by the contractor, it shall be brought to the required level by the contractor at his own cost by filling in with earth duly watered, consolidated and rammed. 2.7.8 In case the excavation is done wider than that shown on the drawings or as required by the Engineer-in-Charge, additional filling wherever required on the account shall be done by the contractor at his own cost. 2.7.9 The excavation shall be done manually or by mechanical means as directed by Engineer-in-charge considering feasibility, urgency of work, availability of labour /mechanical equipments and other factors involved. Contractor shall ensure every safety measures for the workers. Neither any deduction will be made nor any extra payment will be made on this account. 2.8 EXCAVATION IN ORDINARY/HARD ROCK 2.8.1 All excavation operations shall include excavation and ‘getting out’ the excavated matter. In case of excavation for trenches, basements, water tanks etc. ‘getting out’ shall include throwing the excavated materials at a distance of at least one metre or half the depth of excavation, whichever is more, clear off the edge or excavation. In all other cases ‘getting out’ shall include depositing the excavated materials as specified. The subsequent disposal of the excavated material shall be either stated as a separate item or included with the item of excavation stating lead. 2.8.2 During the excavation, the natural drainage of the area shall be maintained. Excavation shall be done from top to bottom. Undermining or under cutting shall not be done. 2.8.3 Where hard rock is met with and blasting operations are considered necessary, the contractor shall obtain the approval of the Engineer-in-Charge in writing for resorting to the blasting operations. Blasting operations shall be done as specified in para 2.6 and chiseling shall be done to obtain correct levels, slopes, shape and pattern of excavation as per the drawings or as required by the Engineer-in-Charge and nothing extra shall be payable for chiseling. 2.8.4 Where blasting operations are prohibited or are not practicable, excavation in hard rock shall be done by chiseling. 2.8.5 In ordinary rock excavation shall be carried out by crowbars, pick axes or pneumatic drills and blasting operation shall not be generally adopted. Where blasting operations are not prohibited and it is practicable to resort to blasting for excavation in ordinary rock, contractor may do so with the permission of the Engineer-in-Charge in writing but nothing extra shall be paid for this blasting. Blasting shall be done as specified in para 2.6. 2.8.6 If the excavation for foundations or drains is done to a depth greater than that shown in the drawings or as required by the Engineer-in-Charge. The excess depth shall be made good by the contractor at his own cost with the concrete of the mix used for levelling/ bed concrete for foundations. Soft/ defective spots at the bed of foundations shall be dug out and filled with concrete (to be paid separately) as directed by the Engineer-in-Charge. 35

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2.8.7 In all other cases where the excavation is taken deeper by the contractor, it shall be brought to the required level by the contractor at his own cost by filling with earth duly watered, consolidated and rammed. 2.8.8 In case the excavation is done wider than that shown on the drawings or as required by the Engineer-in-Charge, filling wherever required on this account shall be done by the contractor at his own cost. 2.8.9 Only the excavation shown on the drawings or as required by the Engineer-in-Charge shall be measured and recorded for payment except in case of hard rock, where blasting operations have been resorted to, excavation shall be measured to the actual levels, provided the Engineer-in-Charge is satisfied that the contractor has not gone deeper than what was unavoidable. 2.8.10 The excavation shall be done manually or by mechanical means as desired by Engineer-inCharge considering feasibility, urgency of work, availability of labour /mechanical equipments and other factors involved Contractor shall ensure every safety measures for the workers. Neither any deduction will be made nor any extra payment will be made on this account. 2.9

EARTH WORK BY MECHANICAL MEANS Earth work by mechanical means involves careful planning keeping in view site conditions i.e. type of soil, nature of excavation, distances through which excavated soil is to be transported and working space available for employing these machines. The earth moving equipment should be accordingly selected. The earth moving equipment consists of excavating and transporting equipment. Excavating equipments may be further classified as excavators and tractor based equipments. 2.9.1 Excavators Excavators generally used at site are as follows: (i) Dipper–shovel : It is used for excavating against a face or bank consisting of open-top bucket or dipper with a bottom opening door, fixed to an arm or dipper stick which slides and pivots on the jib of the crane. It is suitable for excavating all clay chalk and friable materials and for handling rock and stone. However, it is not suitable for surface excavation for which a skimmer is used. (ii) Backhoe : It is similar to face shovel except that the dipper stick pivots on the end of the jib and the dipper or bucket works towards the chassis and normally has no bottom door but is emptied by swinging away from the chassis to invert the bucket. It may be designed to carry both a front –mounted bucket loading mechanism and a rear mounted backhoe. It is mainly used to excavate trenches and occasionally used for the excavation of open areas such as small basements. In the backhoe mode the bucket lifts, swings and discharges materials while the undercarriage is stationary. When used in the ‘loader’ mode, the machine loads or excavated through forward motion of the machine, and lifts, transports and discharges materials. (iii) Skimmer : This arrangement is similar to the face shovel except that in this case the bucket slides on rollers directly along the jib and thus has a more restricted movement. It is used for surface excavation and levelling in conjunction with transport to haul away the excavated material. (iv) Dragline : It is usually fitted with a long slender boom or jib and the bucket, which in operation faces towards the machine and has no door, is supported by cable only as on a crane. It works from the side of the excavation at normal ground level and is used for excavating large open excavations such as basements when the depth is beyond the limit of the boom of a backhoe. It is commonly used for open cast mining operations. CPWD SPECIFICATIONS 2009

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(v) Clamshell : It consists of two hinged half-buckets or jaws pivoted to a frame which is suspended by cable from a long jib of an excavation. The grab is used for deep excavations of limited area on all types of soil except rock. Crane and Grab is a variant of this type of equipment. 2.9.2 Tractor–based Equipment It is a self–propelled crawler or wheeled machine used to exert a push or pull force through mounted equipment. It is designed either as attachments to normal tracked or wheeled tractors or as machines in which the earth moving attachments and the tractor are designed as a single integrated unit. A tractor, which is hydraulically operated, can be rigged as : (i) Loaders : It is used for loading, light dozing, scraping and grabbing operations, lifting and transporting the materials (loose earth, rubble, sand, gravel aggregate etc) at various sites through forward motion of the machine. (ii) Tractor Shovel : This consists of a tipping bucket at the front attached by strong pivoted arms or booms to the frame of the machine. It is used for stripping top soil, excavating against a face, bulldozing and for loading spoil or loose materials. It is similar to crawler dipper-shovel. (iii) Trench Digger : It operates on the same principle as a backhoe excavator except that the bucket is controlled by hydraulic rams instead of cables and pulleys. (iv) Scraper : Scrapers provide unique capability to excavate, load, haul and dump materials. Scrapers are available in various capacities by a number of manufacturers with options such as self – loading with elevators, twin engines or push-pull capability. They are cost effective where the haul distance is too long for bulldozers, yet too short for trucks. This distance typically ranges from 120 m to 1200 m; however, the economics should be evaluated for each project. Scraper has an open bowl with a cutting edge positioned between the axles, which cuts, loads, transports, discharges and spreads through forward motion of the machine. Loading through forward motion of the machine can be assisted by a powered mechanism (elevator) fixed to the scraper bowl. (v) Bulldozer and Angle-dozer : The most common equipment used for clearing and levelling activities is a bulldozer. The terms bulldozer is used to define a tractor mounted with a dozing blade. The bulldozer consists of a rectangular steel blade with renewable cutting edge set at right angles (capable of only tilting but not angling) to the direction of travel and attached by steel arms to the side frames of a crawler tractor. It may be used for excavating natural soil or for moving loose soil or debris, which is pushed forward as the tractor forces it ahead. (vi) Angledozer is capable of both tilting and angling 2.9.3 Transporting Equipment This implies horizontal movement primarily but it can involve some vertical movement too. (i) Dumpers : These are self-propelled wheeled machines, having an open body. It is designed for the transport of excavated materials and consists of a shallow tipping hopper or skip mounted on a wheeled chassis, such as, power barrow, dumper, multi-skip dumpers, high discharge dumpers, dump truck, etc. These can be rear dump, side dump or bottom dump. (ii) Vibratory Roller : It is a single Drum Vibratory Roller for compaction of embankments, etc. The smooth drum version is for compaction of granular and mixed soil. The sheepsfoot Roller consists of a hallow cylindrical steel drum or drums on which projecting feet are mounted. These 37

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feet penetrate into the fill as a roller moves forward and cause compaction. The geometry of the foot may be sheep, club pyramid, cone or cylinder foot. Such rollers are employed for compaction (densification) of cohesive and semi-cohesive soils. 2.10 FILLING 2.10.1 The earth used for filling shall be free from all roots, grass, shrubs, rank vegetation, brushwood, tress, sapling and rubbish. 2.10.2 Filling with excavated earth shall be done in regular horizontal layers each not exceeding 20 cm in depth. All lumps and clods exceeding 8 cm in any direction shall be broken. Each layer shall be watered and consolidated with steel rammer or ½ tonne roller. Where specified, every third and top must layer shall also be consolidated with power roller of minimum 8 tonnes. Wherever depth of filling exceeds 1.5 metre vibratory power roller shall be used to consolidate the filing unless otherwise directed by Engineer-in-charge. The top and sides of filling shall be neatly dressed. The contractor shall make good all subsidence and shrinkage in earth fillings, embankments, traverses etc. during execution and till the completion of work unless otherwise specified. 2.11 MEASUREMENTS 2.11.1 The length and breadth of excavation or filling shall be measured with a steel tape correct to the nearest cm. The depth of cutting or height of filling shall be measured, correct to 5 mm, by recording levels before the start of the work and after the completion of the work. The cubical contents shall be worked out to the nearest two places of decimal in cubic metres. 2.11.1.1 In case of open footings up to the depth of 1.5 metres, alround excavation of 30 cm. beyond the outer dimension of footing shall be measured for payment to make allowances for centering and shuttering. Any additional excavation beyond this limit shall be at the risk and cost of the contractor and shall not be measured for payment. 2.11.1.2 In case of open footings/Rafts at a depth of more than 1.5 metre, alround excavation of 75 cm shall be measured for payment to make allowance for centering and shuttering. Additional excavation beyond this limit shall be at the risk and cost of the contractor and shall not be measured for payment. 2.11.2 In case the ground is fairly uniform and where the site is not required to be levelled, the Engineer-in-Charge may permit the measurements of depth of cutting or height of filling with steel tape, correct to the nearest cm. In case of borrow pits, diagonal ridges, cross ridges or dead-men, the position of which shall be fixed by the Engineer-in-Charge, shall be left by the contractor to permit accurate measurements being taken with steel tape on the completion of the work Deduction of such ridges and dead men shall be made from the measurements unless the same are required to be removed later on and the earth so removed is utilized in the work. In the latter case nothing extra will be paid for their removal as subsequent operation. 2.11.3 Where ordinary rock and hard rock is mixed. The measurement of the excavation shall be made as specified in 2.11.1 and 2.11.2 The two kinds of rock shall be stacked separately and measured in stacks. The net quantity of the two kinds of rocks shall be arrived at by applying deduction of 50% to allow for voids in stacks. If the sum of net quantity of two kinds of rocks exceeds the total quantity of the excavated material, then the quantity for each type of rock shall be worked out from the total quantity in the ratio of net quantities in stack measurements of the two types of rocks. If in the opinion of the Engineering-in-charge stacking is not feasible, the quantity of ordinary and hard rock shall be worked out by means of cross-sectional measurements. 2.11.4 Where soil, ordinary rock and hard rock are mixed, the measurements for the entire excavation shall be made as specified in 2.11.1 and 2.11.2 Excavated materials comprising hard rock and ordinary rock shall be stacked separately, measured, and each reduced by 50% to allow for voids to arrive at the CPWD SPECIFICATIONS 2009

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quantity payable under hard rock and ordinary rock. The difference between the entire excavation and the sum of the quantities payable under hard rock and ordinary rock shall be paid for as excavation in ordinary soil or hard soil as the case may be. 2.11.5 Where it is not possible or convenient to measure the depth of cutting by recording levels as specified in 2.11.1 quantity of excavation shall be worked out from filling. The actual measurements of the fill shall be calculated by taking levels of the original ground before start of the work after site clearance and after compaction of the fill as specified and the quantity of earth work so computed shall be reduced by 10% in case of consolidated fills and by 5% in case the consolidation is done by heavy mechanical machinery to arrive at the net quantity of excavation for payment. No such deduction shall, however, be made in case of consolidation by heavy mechanical machinery at optimum moisture content, or when the consolidated filling is in confined situations such as under floors. 2.11.6. Recording Measurements for Earth Levelling Work 2.11.6.1 Level Books: In case of levelling operations and earthwork, measurements are required to be recorded in level books in addition to Measurement Books. The Level Books should be numbered, accounted for and handled like Measurement Books. 2.11.6.2 Preparatory Works: Before starting the earth work, following steps should be taken : (1) Original ground levels should be recorded in the Level Book in the presence of the contractor or his authorized representative, and should be signed by him and the Department Officer who records the levels. All the local mounds and depressions should be indicated clearly in the drawing and the field Level Book and should be checked by the Assistant Engineer/Executive Engineer before the levelling work is started. (2) A suitable baseline should be fixed with permanent masonry pillars at distances not exceeding 150 metres to provide a permanent reference line for facilitating check work. The base line (s) should be entered in the Level Book with co-ordinates. These baselines should be maintained till the final payment for the work has been made. (3) While recording the levels, it should be ensured that the circuit is closed by taking final levels of the starting point or any other point, the R.L. of which was previously determined. (4) Plans showing initial levels, location of bench marks and reduced levels, should be prepared and signed by both the parties and attached to the agreement before commencement of the work. 2.11.6.3 Test Check of the Levels (1) The Assistant Engineer should exercise test check at least to the extent of 50%, and the Executive Engineer at least to the extent of 10% where the value of this item of work exceeds 10% of the tender acceptance power of the Assistant Engineer. (2) The test check of the levels should be carried out independently by each officer, and the readings should be recorded in the prescribed Level Book in red ink against the old levels which should be neatly scored out wherever necessary. If the test check carried out reveals serious mistakes in the original levels, these should be taken or re-taken and re-checked. (3) The test check carried out by an officer should be as representative as possible for the entire work done. (4) On completion of work, the levels should again be recorded in the Level Book and the contractor’s signatures obtained. These levels should also be test checked by the Assistant Engineer/Executive Engineer to the same extent as indicated in (1) within one month of the date of completion of the earth work, and according to the procedure as laid down in the case of initial levels as indicated above. (5) The formation levels as per final execution of the work should be compared with the proposed formation levels and the work got rectified within permissible tolerance. 39

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2.11.6.4 Payment of Leveling Work (1) Every fourth running bill and the final bill should be paid on the basis of levels. (2) Intermediate payments can, however, be made on the basis of borrow pit measurements. The Executive Engineer should take care that the quantities thus assessed are not in any case more than the actual work done. 2.11.6.5 Large Scale Leveling Work (1) In case of large scale levelling work involving both cutting and filling, an accurate site plan should be prepared before the work is commenced. The portions requiring cutting and filling shall then be divided into squares and corresponding squares into filling, which are complementary to the squares in cutting given the same number. (2) A table may be written upon the plan showing leads involved between the various complementary squares. This would form a lead chart for the work to be done. (3) Before the work of levelling is commenced, the lead chart shall be checked by the Assistant Engineer in the presence of the contractor or his authorized representative, and his signatures shall be obtained on the same. This should form an integral part of the contract and should be duly signed by both the integral parties before commencement of the work. (4) The quantity payable for earthwork shall be lower of the quantity derived from cutting or filling. The payment for lead shall be based on lead chart prepared in the aforesaid manner. 2.11.6.6 Import of Earth: In case of earth to be imported, the area from where the earth is to be imported, should be pre-determined wherever possible before the start of the work, and wherever feasible, the average lead should be worked out and stipulated in the tender. After this is determined, initial levels of the area to be filled should be recorded. The levels should be properly checked during the progress of work and on completion. 2.12 RATES 2.12.1 Rates for Earthwork shall include the following: (a) Excavation and depositing excavated material as specified. (b) Handing of antiquities and useful material as specified on 2.2. (c) Protection as specified in 2.3. (d) Site clearance as specified in 2.4. (e) Setting out and making profiles as specified in 2.5. (f) Forming (or leaving) dead – men or ‘Tell Tales’ in borrow pits and their removal after measurements. (g) Bailing out or pumping of rain water from excavations. (h) Initial lead of 50 m and lift of 1.5 m. (i) Blasting operations for hard rock as specified in 2.6. 2.12.2 No deduction shall be made from the rate if in the opinion of the Engineer- in-charge, operations specified in 2.12.1 (b) to (h) are not required to be carried out on any account whatsoever. 2.13 SURFACE EXCAVATION 2.13.1 Excavations exceeding 1.5 m in width and 10 sqm. on plan but not exceeding 30 cm. in depth in all types of soils and rocks shall be described as surface excavation and shall be done as specified in 2.7 and 2.8. 2.13.1 Measurements The length and breadth shall be measured with a steel tape correct to the nearest cm. and the area worked out to the nearest two places of decimal in square metres.

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2.13.3 Rate shall be as specified in 2.12. 2.14. ROUGH EXCAVATION AND FILLING 2.14.1 Excavation for earth from borrow pits, cutting hill side slopes etc. shall be described as rough excavation and shall be done as specified in 2.7, 2.8 and 2.9. 2.14.2 Wherever filling is to be done, the earth from excavation shall be directly used for filling and no payment for double handling of earth shall be admissible. Filling of excavated earth shall be done as specified in 2.10. In case of hill side cutting, where the excavated materials is thrown down the hill slopes, payment for filling excavated earth shall not be admissible. 2.14.3 Measurements shall be as specified in 2.11. 2.14.4 Rates shall be as specified in 2.12. 2.15 EXCAVATION OVER AREA (ALL KINDS OF SOIL) 2.15.1 This shall comprise: (a) Excavation exceeding 1.5 m in width and 10 sqm on plan and exceeding 30 cm in depth. (b) Excavation for basements, water tanks etc. (c) Excavation in trenches exceeding 1.5 m in width and 10 sqm on plan. 2.15.2 Excavation shall be done as specified in 2.7. 2.15.3 Measurements shall be as specified in 2.11. 2.15.4 Rates shall be as specified in 2.12. 2.16 EXCAVATION OVER AREA (ORDINARY/ HARD ROCK) 2.16.1 This shall comprise: (a) Excavation exceeding 1.5 m in width and 10 sqm on plan and exceeding 30 cm in depth. (b) Excavation for basements, water tanks etc. (c) Excavation in trenches exceeding 1.5 m in width and 10 sqm on plan. 2.16.2 Excavation shall be done as specified in 2.8 and 2.9. 2.16.3 Measurements shall be done as specified in 2.11. 2.16.4 Rates shall be as specified in 2.12. 2.17 EXCAVATION IN TRENCHES FOR FOUNDATIONS AND DRAINS (ALL KINDS OF SOIL) 2.17.1 This shall comprise excavation not exceeding 1.5 m in width or 10 sqm on plan and to any depth in trenches (excluding trenches for pipes, cables, conduits etc.) 2.17.2 Excavation shall be done as specified in 2.7. 2.17.3 Measurements shall be as specified in 2.11. 2.17.4 Rates shall be as specified in 2.12. 2.18 EXCAVATION IN TRENCHES FOR FOUNDATION AND DRAINS (ORDINARY/ HARD ROCK) 2.18.1 This shall comprise excavation not exceeding 1.5m in width or 10 sqm. On plan and to any depth in trenches (excluding trenches for pipes, cables, conduits etc.)

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2.18.2 Excavation shall be done as specified in 2.8. and 2.9. 2.18.3 Measurements shall be as specified in 2.11. 2.18.4 Rates shall be as specified in 2.12. 2.19 EXCAVATION IN TRENCHES FOR PIPES, CABLES ETC. AND REFILLING 2.19.1 This shall comprise excavation not exceeding 1.5 mts in width or 10 sqm in plan and to any depth trenches for pipes. Cables etc. and returning the excavated material to fill the trenches after pipes, cables etc. are laid and their joints tested and passed and disposal of surplus excavated material upto 50 m lead. 2.19.2 Width of Trench (a) Upto one metre depth the authorized width of trench for excavation shall be arrived at by adding 25 cm to the external diameter of pipe (not socket/ collar) cable, conduit etc. Where a pipe is laid on concrete bed/ cushioning layer, the authorized width shall be the external diameter of pipe (not socket/ collar) plus 25 cm or the width of concrete bed/ cushioning layer whichever is more. (b) For depths exceeding one metre, an allowance of 5 cm per metre of depth for each side of the trench shall be added to the authorized width (that is external diameter of pipe plus 25 cm) for excavation. This allowance shall apply to the entire depth of the trench. In firm soils the sides of the trenches shall be kept vertical upto depth of 2 metres from the bottom. For depths greater than 2 metres, the excavation profiles shall be widened by allowing steps of 50 cm on either side after every two metres from bottom. (c) Where more than one pipe, cable, conduit etc, are laid, the diameter shall be reckoned as the horizontal distance from outside to outside of the outermost pipes, cable, conduit etc. (d) Where the soil is soft, loose or slushy, width of trench shall be suitably increased or side sloped or the soil shored up as directed by the Engineer-in-Charge. It shall be the responsibility of the contractor to take complete instructions in writing from the Engineer-in-Charge regarding increase in the width of trench. Sloping or shoring to be done for excavation in soft, loose or slushy soils. 2.19.3 Excavation : Shall be done as specified in 2.7, 2.8 and 2.9. 2.19.4 Refilling Filling in trenches shall be commenced soon after the joints of pipes, cables, conduits etc. have been tested and passed. The space alround the pipes, cables conduits etc. shall be cleared of all debris, brick bats etc. Where the trenches are excavated in hard/ soft soil, the filling shall be done with earth on the side and top of pipes in layers not exceeding 20 cm in depth. Each layer shall be watered, rammed and consolidated. All clods and lumps of earth exceeding 8 cm in any direction shall be broken or removed before the excavated earth is used for filling. In case of excavation trenches in ordinary/ hard rock, the filling upto a depth of 30cm above the crown of pipe, cable, conduits etc. shall be done with fine material like earth, moorum or pulverized/ decomposed rock according to the availability at site. The remaining filling shall be done with boulders of size not exceeding 15cm mixed with fine material like decomposed rock, moorum or earth as available to fill up the voids, watered, rammed and consolidated in layers not exceeding 30cm. Excavated material containing deleterious material, salt peter earth etc. shall not be used for filling. Ramming shall be done with iron rammers where feasible and with blunt ends of crow bars where rammers cannot be used. Special care shall be taken to ensure that no damage is caused to the pipes, Cables, Conduits etc. laid in the trenches. 2.19.5 Measurements 2.19.5.1 Trenches for pipes, cables, conduits etc. shall be measured in running metre correct to the nearest cm in stages of 1.5 m depth and described separately as under: (a) Pipes, cables, conduits, etc. not exceeding 80 mm dia. CPWD SPECIFICATIONS 2009

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(b) Pipes, cables, conduits etc. exceeding 80 mm dia but not exceeding 300mm dia. (c) Pipes, cables, conduits etc. exceeding 300 mm dia. 2.19.5.2 Where two or more categories of each work are involved due to different classification of soil within the same stage of trench depth or where the soil is soft loose or slushy requiring increase in the width of trench or sloping sides or shoring, trenches for pipes, cables, conduits, etc. shall be measured in cubic metres as specified in 2.10. Extra excavation, if any, on account of collar/ socket of pipes shall neither be measured nor paid for separately. 2.19.6 Rates The rate shall be as specified in 2.12 and shall also include the cost of refilling and all other operations described above. 2.20 PLANKING AND STRUTTING 2.20.1 When the depth of trench in soft/loose soil exceeds 2 metres, stepping, sloping and/ or planking and strutting of sides shall be done. In case of loose and slushy soils, the depths at which these precautions are to be taken, shall be determined by the Engineer-in-Charge according to the nature of soil. Planking and strutting shall be ‘close’ or ‘open’ depending on the nature of soil and the depth of trench. The type of planking and strutting shall be determined by the Engineer-in-Charge. It shall be the responsibility of the contractor to take all necessary steps to prevent the sides of trenches from collapse. Engineer-in-Charge should take guidance from IS: 3764 for designing the shoring and strutting arrangements and specifying the profile of excavation. 2.20.2 Close Planking and Strutting Close planking and strutting shall be done by completely covering the sides of the trench generally with short upright, members called ‘poling boards’. These shall be 250x38 mm in section or as directed by the Engineer-in-Charge. The boards shall generally be placed in position vertically in pairs. One boards on either side of cutting. These shall be kept apart by horizontal wallings of strong wood at a maximum spacing of 1.2 metres cross strutted with ballies, or as directed by Engineer-in-Charge. The length and diameter of the ballies strut shall depend upon the width of the trench. Typical sketch of close timbering is given in Fig. 2.2. Where the soil is very soft and loose, the boards shall be placed horizontally against the sides of the excavation and supported by vertical ‘wallings’ which shall be strutted to similar timber pieces on the opposite face of the trench. The lowest boards supporting the sides shall be taken in the ground for a minimum depth of 75 mm. No portion of the vertical side of the trench shall remain exposed. The withdrawal of the timber members shall be done very carefully to prevent collapse of the trench. It shall be started at one end and proceeded systematically to the other end. Concrete or masonry shall not be damaged while removing the planks. No claim shall be entertained for any timber which cannot be withdrawn and is lost or buried, unless required by the Engineer-in-Charge to be left permanently in position. 2.20.3 Open Planking and Strutting In case of open planking and strutting, the entire surface of the side of the trench is not required to be covered. The vertical boards 250 mm wide & 38 mm thick, shall be spaced sufficiency apart to leave unsupported strips of 50 cm average width. The detailed arrangement, sizes of the timber and the distance apart shall be subject to the approval of the Engineer-in-Charge. In all other respect, specifications for close planking and strutting shall apply to open planking and strutting. Typical sketch of open planking and strutting is given in fig. 2.2.

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2.20.4 Measurements The dimensions shall be measured correct to the nearest cm and the area of the face supported shall be worked out in square metres correct to two places of decimal. 2.20.4.1 Works shall be grouped according to the following: (a) Depth not exceeding 1.5 m. (b) Depth exceeding 1.5m in stages of 1.5 m. 2.20.4.2 Planking and strutting to the following shall be measured separately: (a) Trenches. (b) Areas- The description shall include use and waste of raking shores. (c) Shafts, walls, cesspits, manholes and the like (d) Where tightly driven close but jointed sheeting is necessary as in case of running sheeting is necessary as in case of running sand the item shall be measured separately and packing of cavities behind sheeting with suitable materials included with the item. (e) Planking and strutting required to be left permanently in position shall be measured separately. 2.20.5 Rates Rates shall include use and waste of all necessary timber work as mentioned above including fixing and subsequent removal. 2.21 EXCAVATION IN WATER. MUD OR FOUL POSITION 2.21.1 All water that may accumulate in excavations during the progress of the work from springs, tidal or river seepage, broken water mains or drains (not due to the negligence of the contractor), and seepage from subsoil aquifer shall be bailed, pumped out or otherwise removed. The contractor shall take adequate measures for bailing and/or pumping out water from excavations and/or pumping out water from excavations and construct diversion channels, bunds, sumps, coffer dams etc. as may be required. Pumping shall be done directly from the foundation trenches or from a sump out side the excavation in such a manner as to preclude the possibility of movement of water through any fresh concrete or masonry and washing away parts of concrete or mortar. During laying of concrete or masonry and for a period of at least 24 hours thereafter, pumping shall be done from a suitable sump separated from concrete or masonry by effective means. Capacity and number of pumps, location at which the pumps are to be installed, pumping hours etc. shall be decided from time to time in consultation with the Engineer-in-Charge. Pumping shall be done in such a way as not to cause damage to the work or adjoining property by subsidence etc. Disposal of water shall not cause inconvenience or nuisance in the area or cause damage to the property and structure nearby. To prevent slipping of sides, planking and strutting may also be done with the approval of the Engineer-in-Charge. 2.21.2 Classification The earth work for various classification of soil shall be categorised as under: (a) Work in or under water and/or liquid mud: Excavation, where water is met with from any of the sources specified in 2.21.1 shall fall in this category. Steady water level in the trial pits before the commencement of bailing or pumping operations shall be the sub-soil water level in that area. (b) Work in or under foul position: Excavation, where sewage, sewage gases or foul conditions are met with from any source, shall fall in this category. Decision of the Engineer-in-Charge whether the work is in foul position or not shall be final.

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2.21.3 Measurements 2.21.3.1 The unit, namely, metre depth shall be the depth measured from the level of foul position/ subsoil water level and upto the centre of gravity of the cross sectional area of excavation actually done in the conditions classified in 2.21.2. Metre depth shall be reckoned correct to 0.1 m, 0.05 m or more shall be taken as 0.1 m and less than 0.05 m ignored. The extra percentage rate is applicable in respect of each item but the measurements shall be limited only to the quantities of earth work actually executed in the conditions classified in 2.21.2. 2.21.3.2 In case earth work in or under foul position is also in or under water and/or liquid mud, extra payment shall be admissible only for the earth work actually executed in or under foul position. 2.21.3.3 Pumping or bailing out water met within excavations from the sources specified in 2.21.1 where envisaged and specifically ordered in writing by the Engineer-in-Charge shall be measured separately and paid. Quantity of water shall be recorded in kilolitres correct to two places of decimal. This payment shall be in addition to the payment under respective items of earthwork and shall be admissible only when pumping or bailing out water has been specifically ordered by the Engineer-in-Charge in writing. 2.21.3.4 Planking and strutting or any other protection work done with the approval of the Engineer-inCharge to keep the trenches dry and/or to save the foundations against damage by corrosion of rise in water levels shall be measured and paid for separately. 2.21.3.5 Bailing or pumping out water, accumulated in excavation, due to rains is included under respective items of earthwork and is not to be paid separately. 2.21.4 Rates The rates for respective items described above shall include cost of all the operations as may be applicable. 2.22 EARTH WORK FOR MAJOR WORKS 2.22.1 Excavation shall be undertaken to the width of the Basement/Retaining wall footing including necessary margins for construction operation as per drawing or directed otherwise. Where the nature of soil or the depth of the trench and season of the year, do not permit vertical sides, the contractor at his own expense shall put up the necessary shoring, strutting and planking or cut slopes with or without steps, to a safer angle or both with due regard to the safety of personnel and works and to the satisfaction of the Engineer. Measurement of plan area of excavation for payment shall be permitted only. 2.22.2 All the major excavation shall be carried out by mechanical excavator. No extra payment shall be made for that. 2.22.3 The contractor shall make at his own cost all necessary arrangements for maintaining water level, in the area where works are under execution low enough so as not to cause any harm to the work shall be considered as inclusive of pumping out or bailing out water, if required, for which no extra payment shall be made. This will include water coming from any source, such as rains, accumulated rain water, floods, leakages from sewer and water mains, subsoil water table being high or due to any other cause whatsoever. The contractor shall make necessary provision of pumping, dredging bailing out water coming from all above sources and excavation and other works shall be kept free of water by providing suitable system approved by the Engineer-in-charge. Sub-soil water table at work site is reported to be about approx. 6.5 m. below the general ground level as observed in the month of April. The water level is likely to rise up to 1 to 2 m. during rainy season. In order to avoid possibility of basement floor of main building being getting uplifted/damaged due to water pressure, the contractor shall lower the ground water table below the proposed foundation level by boring tube wells all around the proposed building using well point sinking method or any 45

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suitable method as approved by Engineer-in-charge. Sub soil water table shall be maintained at least 50 cm. below the P.C.C. level during laying of P.C.C. water proofing treatment, laying of basement raft and beams including filling of earth/sand under the basement floor. The water table shall not be allowed to rise above base of raft level until completion of outer retaining walls including water proofing of vertical surface of walls and back filling along the walls upto ground level and until the structure attains such height to counter balance the uplift pressure. However, the contractor should inspect the site and make his own assessment about sub-soil water level likely to be encountered at the time of execution and quote his rates accordingly. Rate of all items are inclusive of pumping out or bailing out water, if required. Nothing extra on this account whatsoever shall be paid to him. The sequence of construction shall be got approved by the Engineer-in-charge. 2.22.4 The contractor shall take all necessary measures for the safety of traffic during construction and provide, erect and maintain such barricades including signs, markings, flags, lights and flagman, as necessary at either end of the excavation/embankment and at such intermediate points as directed by the Engineer-in-charge for the proper identification of construction area. He shall be responsible for all damages and accidents caused due to negligence on his part. 2.22.5 The contractor shall provide suitable barricading with suitably painted single row of G.I. Sheets about 3’- 0” wide (90 cms.) nailed or bolted with wooden poles spaced 2 to 3 metre apart and each pole 1.6 m to 2 m long 8 cm. to 10 cm. dia. The poles will be embedded in mobile iron pedestal rings suitably framed for giving stable support as per direction of the Engineer-in-charge. All management (including watch and ward) of barricades shall be the full responsibility of the contractor. The barricades shall be removed only after completion of the work or part of the work. The contractor’s rate shall include all above items of work and nothing extra shall be paid to the contractor over and above his quoted rates. 2.23 FILLING IN TRENCHES, PLINTH, UNDER FLOOR ETC. 2.23.1 Earth Normally excavated earth from same area shall be used for filling. Earth used for filling shall be free from shrubs, rank, vegetation, grass, brushwood, stone shingle and boulders (larger than 75mm in any direction), organic or any other foreign matter. Earth containing deleterious materials, salt peter earth etc. shall not be used for filling. All clods and lumps of earth exceeding 8 cm in any direction shall be broken or removed before the earth is used for filling. 2.23.2 Filling The space around the foundations and drains in trenches shall be cleared of all debris, brick bats etc. The filling shall be done in layers not exceeding 20 cm in depth. Each layer shall be watered, rammed and consolidated. Ramming shall be done with iron rammers where possible and with blunt end of crow bars where rammers cannot be used. Special care shall be taken to ensure that no damage is caused to the pipes, drains, masonry or concrete in the trenches. In case of filling under floor, the finished level of filling shall be kept to the slope intended to be given to the floor. 2.23.3 Measurements 2.23.3.1 Filling Side of Foundations: The cubical contents of bed concrete levelling course and masonry/ concrete in foundations upto the ground level shall be worked out and the same deducted from the cubical contents of earthwork in excavation for foundations already measured under the respective item of earth work to arrive at the quantity for filling sides of foundation. The quantity shall be calculated correct to two places of decimal. 2.23.3.2 Filling in Plinth and under Floors: Depth of filling shall be the consolidated depth. The dimensions of filling shall be on the basis of pre-measurement correct to the nearest cm and cubical content worked out in cubic metres correct to two places of decimal. 2.23.4 Rates The rates include cost of all the operations described above.

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2.24 SAND FILLING IN PLINTH 2.24.1 Sand Sand shall be clean and free from dust organic and foreign matter and its grading shall be within the limits of grading zone IV or V specified in Section 3 ‘Mortars’. 2.24.2 Filling Sand filling shall be done in a manner similar to earth filling in plinth specified in 2.23.3.2. except that consolidation shall be done by flooding with water. The surface of the consolidated sand filling shall be dressed to the required level or slope and shall not be covered till the Engineer-in-Charge has inspected and approved the sand filling. 2.24.3 Measurements The length, breadth and depth of consolidated sand shall be measured with steel tape correct to the nearest cm and cubical contents worked out in cubic metres correct to two places of decimal. 2.24.4 Rates The rates include the cost of material and labour involved in all the operations described above. 2.25 SURFACE DRESSING. 2.25.1 Surface dressing shall include cutting and filling upto a depth of 15 cm and clearing of shrubs, rank vegetation, grass, brushwood, trees and saplings of girth upto 30 cm measured at a height of one metre above the ground level and removal of rubbish and other excavated material upto a distance of 50 metres outside the periphery of the area under surface dressing. High portions of the ground shall be cut down and hollows depression filled upto the required level with the excavated earth so as to give an even, neat and tidy look. 2.25.2 Measurements Length and breadth of the dressed ground shall be measured correct to the nearest cm and the area worked out in square metres correct to two places of decimal. 2.25.3 Rates The rates shall include cost of labour involved in all the operations described above. 2.26 JUNGLE CLEARANCE 2.26.0 Jungle clearance shall comprise uprooting of rank vegetation, grass, brushwood, shrubs, stumps, trees and saplings of girth upto 30 cm measured at a height of one metre above the ground level. Where only clearance of grass is involved it shall be measured and paid for separately. 2.26.1 Uprooting of Vegetations The roots of trees and saplings shall be removed to a depth of 60 cm below ground level or 30 cm below formation level or 15 cm below sub-grade level, whichever is lower. All holes or hollows formed due to removal of roots shall be filled up with earth rammed and levelled. Trees, shrubs, poles, fences, signs, monuments, pipe lines, cable etc., within or adjacent to the area which are not required to be disturbed during jungle clearance shall be properly protected by the contractor at his own cost and nothing extra shall be payable. 2.26.2 Stacking and Disposal All useful materials obtained from clearing and grubbing operation shall be stacked in the manner as directed by the Engineer-in-Charge. Trunks and branches of trees shall be cleared of limbs and tops and stacked neatly at places indicated by the Engineer-in-Charge. The materials shall be the property of the Government. All unserviceable materials which in the opinion of the Engineer-in-Charge cannot be used or auctioned shall be removed up to a distance of 50 m outside the periphery of the area under

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clearance. It shall be ensured by the contractor that unserviceable materials are disposed off in such a manner that there is no likelihood of getting mixed up with the materials meant for construction. 2.26.3 Clearance of Grass Clearing and grubbing operation involving only the clearance of grass shall be measured and paid for separately and shall include removal of rubbish upto a distance of 50 m outside the periphery of the area under clearance. 2.26.4 Measurements The length and breadth shall be measured correct to the nearest cm and area worked out in square metres correct to two places of decimal. 2.26.5 Rates The rate includes cost of all the operation described above. Note: Jungle clearance and clearance of grass are not payable separately for the earth work specified in 2.13 to 2.19. 2.27 FELLING TREES 2.27.1 Felling While clearing jungle, growth trees above 30 cm girth (measured at a height of one metre above ground level) to be cut, shall be approved by the Engineer-in-Charge and then marked at site. Felling trees shall include taking out roots upto 60 cm below ground level or 30 cm below formation level or 15 cm below sub-grade level, whichever is lower. All excavation below general ground level arising out of the removal of trees, stumps etc. shall be filled with suitable material in 20 cm layers and compacted thoroughly so that the surfaces at these points conform to the surrounding area. The trunks and branches of trees shall be cleared of limbs and tops and cut into suitable pieces as directed by the Engineer-in-Charge. 2.27.2 Stacking and Disposal Wood, branches, twigs of trees and other useful material shall be the property of the Government. The serviceable materials shall be stacked in the manner as directed by the Engineer-in-Charge upto a lead of 50m. All unserviceable material, which in the opinion of Engineer-in-Charge cannot be used or auctioned shall be removed from the area and disposed off as per the directions of the Engineer-in-Charge. Care shall be taken to see that unsuitable waste materials are disposed off in such a manner that there is no likelihood of these getting mixed up with the materials meant for construction. 2.27.3 Measurements Cutting of trees above 30 cm in girth (measured at a height of one metre above level) shall be measured in numbers according to the sizes given below: (a) Beyond 30 cm girth, upto and including 60cm girth. (b) Beyond 60 cm girth, upto and including 120 cm girth. (c) Beyond 120 cm girth, upto and including 240 cm girth. (d) Above 240 cm girth. 2.27.4 Rate The rate includes the cost involved in all the operations described above. The contract unit rate for cutting trees above 30 cm in girth shall include removal of stumps as well.

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2.28 ANTI-TERMITE TREATMENT 2.28.0 Sub-terranean termites are responsible for most of the termite damage in buildings. Typically, they form nests or colonies underground. In the soil near ground level in a stump or other suitable piece of timber in a conical or dome shaped mound. The termites find access to the super-structure of the building either through the timber buried in the ground or by means of mud shelter tubes constructed over unprotected foundations. Termite control in existing as well as new building structures is very important as the damage likely to be caused by the termites to wooden members of building and other household article like furniture, clothing, stationery etc. is considerable. Anti-termite treatment can be either during the time of construction i.e. pre-constructional chemical treatment or after the building has been constructed i.e. treatment for existing building. Prevention of the termite from reaching the super-structure of the building and its contents can be achieved by creating a chemical barrier between the ground, from where the termites come and other contents of the building which may form food for the termites. This is achieved by treating the soil beneath the building and around the foundation with a suitable insecticide. 2.28.1 Materials 2.28.1.0 Chemicals: Any one of the following chemicals in water emulsion to achieve the percentage concentration specified against each chemical shall be used: (i) Chlorphriphos emulsifiable concentrate of 20% (ii) Lindane emulsifiable concentrate of 20% Anti-termite treatment chemical is available in concentrated form in the market and concentration is indicated on the sealed containers. To achieve the specified percentage of concentration, Chemical should be diluted with water in required quantity before it is used. Graduated containers shall be used for dilution of chemical with water in the required proportion to achieve the desired percentage of concentration. For example, to dilute chemical of 20% concentration. 19 parts of water shall be added to one part of chemical for achieving 1% concentration. Engineer-in-Charge shall procure the chemical of required concentration in sealed original containers directly from the reputed and authorized dealers, chemical shall be kept in the custody of the Engineerin-Charge or his authorized representatives and issued for use to meet the day’s requirements. Empty containers after washing and concentrated chemical left unused at the end of the day’s work shall be returned to the Engineer-in-Charge or his authorized representative. 2.28.1.1 Measurements: Concentrated chemical in sealed containers shall be measured in litres. Chemicals of different types and concentration shall be measured separately. 2.28.1.2 Rate: The Rate for the concentrated chemical shall include the cost of material, containers and all the operations involved in transportation and delivery at the place specified. 2.28.2 Safety Precautions Chemical used for anti-termite treatment are insecticides with a persistent action and are highly poisonous. This chemical can have an adverse effect upon health when absorbed through the skin, inhaled as vapours or spray mists or swallowed. The containers having emulsifiable concentrates shall be clearly labelled and kept securely closed in stores so that children or pet cannot get at them. Storage and mixing of concentrates shall not be done near any fire source or flame. Persons using these chemical shall be warned that absorption though skin is the most likely source of accidental poisoning. Particular care shall be taken to prevent skin contact with concentrates and prolonged exposure to dilute emulsion shall also be avoided. After handling the concentrates or dilute emulsion. Workers shall wash themselves with soap and water and wear clean 49

SUB HEAD 2.0 : EARTH WORK

clothing, especially before eating. In the event of severe contamination, clothing shall be removed at once and the skin washed with soap and water. If chemical has splashed into the eyes, they shall be flushed with plenty of soap and water and immediate medical attention shall be sought. Care should be taken in the application of chemicals to see that they are not allowed to contaminate wells or springs which serve as source of drinking water. 2.28.3 Anti-Termite Treatment: Constructional Measures The construction measures specified below should be adopted for protection against subterranean termites originating both internally from within the plinth and externally from the area surrounding the building. (i) Earth free from roots, dead leaves, or other organic matter shall be placed and compacted in successive horizontal layers of loose material not more than 200 mm thick. Dry brick shall be inserted at last 50 mm in brick masonry for providing apron floor around the periphery. [See Fig. 2.3(i)] (ii)

Brick on edge masonry in cement mortar shall be laid on the plinth wall. Dry brick shall be placed on the inner side of plinth wall for getting anticipated offset space for coarse sand and on the other side for installing anti-termite masonry groove. In the case of intermediate walls, dry bricks are placed on either side of the brick on edge masonry for getting offset space for coarse sand layer. [See Fig. 2.3(ii)]

(iii)

The dry brick for the anti-termite groove shall be taken out and dense cement concrete 1:3:6 (1 cement : 3 sand : 6 coarse aggregate by volume) sub-floor carpet shall be laid casting the anti-termite groove in position. In case of internal partition walls, the cement concrete sub-floor shall be laid on either side over the dry bricks to sufficient extent for getting staggered vertical joints over the joint of plinth wall and earth filling. [See Fig. 2.3(iii)]

(iv)

Superstructure masonry shall be raised over the dense cement concrete sub floor carpet and over-head jobs completed. [See Fig. 2.3)(iv)]

(v)

The dry brick for coarse sand layer shall be removed and graded sand (of size 3 to 5 mm) layer at least 100 mm thick shall be compacted over the earth filling and underneath the partially laid dense cement concrete sub-floor carpet [See Fig. 2.3)(v)]

(vi)

Dense cement concrete (1:3:6 mix.) sub-floor at least 75 mm thick shall be laid over the sand filling. Necessary finish may be provided to the cement concrete sub-floor carpet. [See Fig. 2.3)(vi)]

(vii) Dry brick provided for apron floor shall be taken out and 600 mm wide formation of earth in 1:30 slope shall be made. Over the formation, 75 mm thick lime concrete 1:3:6 (1 lime:3 sand: 6 coarse aggregate, by volume) shall be laid. [See Fig. 2.3)(vii)] (viii) Over the 75 mm thick like concrete bed at least 25 mm thick cement concrete topping 1:2:4 (1 cement: 2 sand: 4 fine aggregate, by volume) shall be laid and 12 mm thick cement plaster shall be applied on foundation and plinth. [See Fig. 2.3)(viii)] The final recommendations incorporating the constructional details given above (i to viii) are shown in Fig. 2.4. 2.28.4 Anti Termite Treatment : Treatment for Existing Building: Post Construction Treatment 2.28.4.1 Material (i) Chemicals : Any one of the following chemicals conforming to relevant Indian Standards in water emulsion may be used for soil treatment in order to protect a building from termite attack.

CPWD SPECIFICATIONS 2009

50

Chemical with Percent

Relevant Indian Standards

Chlorpyrifos

20EC

IS 8944

Concentration by weight (Active ingredient) 1.0

Lindane

20EC

IS 632

1.0

These chemicals are available in concentrated form in the market and concentration is indicated on the sealed containers. To achieve the specified percentage of concentration, chemicals should be diluted with water in required quantity before it is used. Graduated containers shall be used for dilution of chemicals with water in the required proportion to achieve the desired percentage of concentration. For example, to dilute chemical of 20% concentration, 19 parts of water shall be added to one part of chemical for achieving 1% concentration. Oil or kerosene based solution of chlorpyrifos 20 EC or Lindane 20 EC, 1.0 percent (by weight) concentration is useful for treatment of wood. Engineer-in-charge shall procure the chemical of required concentration in sealed original containers directly from the reputed and authorized representative. Chemical shall be kept in the custody of the Engineer-in-charge or his authorized representatives and issued for use to meet the day’s requirements. Empty containers after washing and concentrated chemical left unused at the end of the day’s work shall be returned to the Engineer-in-charge or his authorized representative. (ii) Measurements : Concentrated chemical in sealed containers shall be measured in litres. Chemicals of different types and concentration shall be measured separately. (iii) Rate : The rate for the concentrated chemical shall include the cost of material, containers and all the operations involved in transportation and delivery at the place specified. (iv) Safety Precautions : Chemical used for antitermite treatment are insecticides with a persistent action and are highly poisonous. This chemical can have an adverse effect upon health when absorbed through the skin, inhaled as vapours or spray mists or swallowed. The containers having emulsifiable concentrates shall be clearly labeled and kept securely closed in stores so that children or pet cannot get at them. Storage and mixing of concentrates shall not be done near any fire source or flame. Persons carrying out chemical soil treatments should familiarize themselves and exercise due care when handling the chemicals whether in concentrated or in diluted form. After handling the concentrates or dilute emulsion, worker shall wash themselves with soap and water and wear clean clothing especially before eating and smoking. In the event of severe contamination, clothing shall be removed at once and the skin washed with soap and water. If chemical has splashed into the eyes, they shall be flushed with plenty of soap and water and immediate medical attention shall be sought. The use of chemical shall be avoided where there is any risk of wells or other water supplies becoming contaminated. 2.28.4.2 Treatment (i) Once the termites have an ingress into the building, they keep on multiplying and destroy the wooden and cellulosic materials, and as such it becomes essential to take measures for protection against termites. Anti termite measures described below are necessary for the eradication and control of termites in existing building. To facilitate proper penetrations of chemical in to the surface to be treated, hand operated pressure pump shall be used. To have proper check for uniform penetration of chemical, graduated containers shall be used. Proper check should be kept so that the specified quantity of chemical is used for the required area during the operation. Chemical treatment for the eradication and control of sub-terranean termites in existing building shall be done as per IS 6313 (Part III). Treatment shall be got done only from the approved specialized agencies using the chemical procured directly by the Engineer-in-Charge from reputed and authorized dealers.

51

SUB HEAD 2.0 : EARTH WORK

(ii) Treatment along outside of foundations: The soil in contact with the external wall of the building shall be treated with chemical emulsion at the rate of 7.5 litres per square metre of vertical surface of the sub-structure to a depth of 300 mm. To facilitate this treatment, a shallow channel shall be excavated along and close to the wall face. The chemical emulsion shall be directed towards the wall at 1.75 litres per running metre of the channel. Rodding with 12 mm diameter mild steel rods at 150 mm apart shall be done in the channel. If necessary, for uniform dispersal of the chemical to 300 mm depth from the ground level. The balance chemical of 0.5 litre per running metre shall then be used to treat the backfill earth as it is returned to the channel directing the spray towards the wall surface. If there is a concrete or masonry apron around the building, approximately 12 mm diameter holes shall be drilled as close as possible to the plinth wall about 300 mm apart, deep enough to reach the soil below and the chemical emulsion pumped into these holes to soak the soil below at the rate of 2.25 litres per linear metre. In soils which do not allow percolation of chemicals to desired depth, the uniform disposal of the chemical to a depth of 300 mm shall be obtained by suitably modifying the mode of treatment depending on site condition. In case of RCC foundations the soil (backfill) in contact with the column sides and plinth beams along with external perimeter of the building shall be treated with chemical emulsion at the rate of 7.5 litres/sqm. of the vertical surface of the structure. To facilitate this treatment, trenches shall be excavated equal to the width of the shovel exposing the sides of the column and plinth beams upto a depth of 300 mm or upto the bottom of the plinth beams, if this level is less than 300 mm. The chemical emulsion shall be sprayed on the backfill earth as it is returned into the trench directing the spray against the concrete surface of the beam or column as the case may be. (iii) Treatment of Soil under Floors : The points where the termites are likely to seek entry through the floor are the cracks at the following locations: (a) At the junction of the floor and walls as result of shrinkage of the concrete; (b) On the floor surface owing to construction defects; (c) At construction joints in a concrete floor, cracks in sections; and (d) Expansion joints in the floor. Chemical treatment shall be provided in the plinth area of ground floor of the structure, wherever such cracks are noticed by drilling 12 mm holes at the junction of floor and walls along the cracks on the floor and along the construction and expansion joints at the interval of 300 mm to reach the soil below. Chemical emulsion shall be squirted into these holes using a hand operated pressure pump to soak the soil below until refusal or upto a maximum of one litre per hole. The holes shall then be sealed properly with cement mortar 1:2 (1 cement: 2 coarse sand) finished to match the existing floors. The cement mortar applied shall be cured for at least 10 days as per instruction of Engineer-in-charge. (iv) Treatment of Voids in Masonry : The movement of termites through the masonry wall may be arrested by drilling holes in masonry wall at plilnth level and squirting chemical emulsions into the holes to soak the masonry. The holes shall be drilled at an angle of 45 degree from both sides of the plinth wall at 300 mm intervals and emulsion squirted through these holes to soak the masonry using a hand operated pump. This treatment shall also be extended to internal walls having foundations in the soil. Holes shall also be drilled at wall corners and where door and window frames are embedded in the masonry or floor at ground. Emulsion shall be squirted through the holes till refusal or to a maximum of one litre per hole. Care shall be taken to seal the holes after the treatment. CPWD SPECIFICATIONS 2009

52

(v) Treatment at Points of Contact of Wood Work : The wood work which has already been damaged beyond repairs by termites shall be replaced. The new timber shall be dipped or liberally brushed at least twice with chemical in oil or kerosene. All existing wood work in the building which is in contact with the floor or walls and which is infested by termites, shall be treated by spraying at the points of contacts with the adjoining masonry with the chemical emulsion by drilling 6 mm holes at a dowonward angle of about 45 degree at junction of wood work and masonry and squirting chemical emulsion into these holes till refusal or to a maximum of half a litre per hole. The treated holes shall then be sealed. Infested wood work in chaukhats, shelves, joints, purlins etc., in contact with the floor or the walls shall be provided with protective treatment by drilling holes of about 3 mm diameter with a downward slant to the core of the wood work on the inconspicuous surface of the frame. These holes should be at least 150 mm centre to centre and should cover in entire frame work. Chemicals shall be liberally infused in these holes. If the wood is not protected by paint or varnish two coats of the chemicals shall be given on all the surfaces and crevices adjoining the masonry. 2.28.4.3 Measurements : All dimensions shall be measured correct to a cm. The measurements shall be made of the surface actually provided with anti termite treatment. Measurements shall be done separately for treatment of foundations, soils under floors, voids in masonry and wood work as detailed below: (i) Treatment along outside of foundations : The measurements shall be made in running metres taking length along the plinth of the building. (ii) Treatment of soil under floors : The measurements shall be made in square metres, inside clear dimensions of rooms, verandah etc. shall be taken. (iii) Treatment of voids in masonry : The measurements shall be made in running metres along the plinth of the building. (iv) Treatment of wood work : The measurements shall be made in running metres for chowkhats, joints, purlins, beams etc. 2.28.4.4 Rates The rate shall include the cost of labour and all other inputs (except concentrated chemical) involved in all the operations described above including drilling, refilling and making good the holes. 2.28.4.5 Treatment of Electrical Fixtures If infestation in electrical fixture (like switch boxes in the wall) is noticed, covers of the switch boxes shall be removed and inside of such boxes shall be treated liberally with 5 per cent Malathion dusting powder. The covers of the switch boxes shall be refixed after dusting.

53

SUB HEAD 2.0 : EARTH WORK

THE DESIGN FOR TEMPORARY SITE BENCH MARK Sub Head : Earthwork Clause : 2.5.1 75 x 75 x 6 mm M.S. PLATE EMBEDED IN CONCRETE & WELDED TO M.S. ROD

25 mm M.S. HEMISPHERICAL BALL WELDED TO PLATE

340 150 20 MM SLIT FOR DRAINAGE

100

25 mm M.S. ROD WELDED TO PLATE

CEMENT CONCRETE 1:2:4

BRICK WORK IN CEMENT MORTAR 1:4

350

LEVEL

GROUND 150 150

CEMENT CONCRETE 1:5:10

150 850 X - SECTIONAL ELEVATION

25

25

560 850

150

340

PLAN DRAWING NOT TO SCALE ALL DIMENSIONS ARE IN M.M.

Fig. 2.1 : Design for Temporary Site Bench Mark

CPWD SPECIFICATIONS 2009

54

CLOSE AND OPEN PLANKING AND STRUTTING Sub Head : Earthwork Clause : 2.20.2 and 2.20.3

X MA

00 06 180

60

0

WALING 100 x 100 POLING BOARD 250 x 38

POLING BOARD 250 X 38 RAKE

2000 STRUTS

2000 MAX 1200 MAX 300

BLOCKING

PLANKING & STRUTTING FOR SHALLOW-WIDE EXCAVATION

CLOSE PLANKING & STRUTTING WITH VERTICAL POLING BOARD

5 00 250

18 00 MA X

WALING 100 X 100

250

600

600

WALING 100 X 100

POLING BOARD 250 X 38 2000

2000 600

POLING BOARD 250 X 38

X M A00 18

STRUTS

CLOSE PLANKING & STRUTTING WITH LONGITUDINAL POLING BOARD

OPEN PLANKING & STRUTTING

DRAWING NOT TO SCALE ALL DIMENSIONS ARE IN M.M.

Fig. 2.2 : Close & Open Planking & Strutting

55

SUB HEAD 2.0 : EARTH WORK

ANTI-TERMITE CONSTRUCTION STAGE -1 Sub Head : Earthwork Clause : 2.28.3(i)

EARTH FILLING 50 GL

100 DRY BRICK FOR APRON FLOOR

Drawing not to Scale All dimensions in millimetres

Fig. 2.3(i) : Anti-Termite Construction – Stage 1

ANTI-TERMITE CONSTRUCTION STAGE -2 Sub Head : Earthwork Clause : 2.28.3(ii)

BRICK ON EDGE IN CEMENT MORTAR DRY BRICK DRY BRICK FOR ANTI-TERMITE GROOVE

100

GL

100 mm OFFSET PROVIDED ON THE INNER SIDE OF OUTER WALL FOR SAND LAYER

Drawing not to Scale All dimensions in millimetres

Fig. 2.3(ii) : Anti-Termite Construction – Stage 2

CPWD SPECIFICATIONS 2009

56

ANTI-TERMITE CONSTRUCTION STAGE -3 Sub Head : Earthwork Clause : 2.28.3(iii) DENSE CEMENT CONCRETE (1:3:6) SUBFLOOR CARPET LAID CASTING ANT-TERMITE GROOVE IN POSITION DRY BRICK

12 mm THICK CEMENT PLASTER 75 75

100

68

100

A

GL 100

DETAIL AT A

Drawing not to Scale All dimensions in millimetres

Fig. 2.3(iii) : Anti-Termite Construction – Stage 3

ANTI-TERMITE CONSTRUCTION STAGE -4 Sub Head : Earthwork Clause : 2.28.3(iv) SUPERSTRUCTURE WALL

50

GL

Drawing not to Scale All dimensions in millimetres

Fig. 2.3(iv) : Anti-Termite Construction – Stage 4 57

SUB HEAD 2.0 : EARTH WORK

ANTI-TERMITE CONSTRUCTION STAGE -5 Sub Head : Earthwork Clause : 2.28.3(v)

DRY BRICKS TAKEN OUT AND 100 mm THICK SAND LAYER LAID AND COMPACTED

GL

Drawing not to Scale

Fig. 2.3(v) : Anti-Termite Construction – Stage 5

ANTI-TERMITE CONSTRUCTION STAGE -6 Sub Head : Earthwork Clause : 2.28.3(vi) SKIRTING COMPLETED 75 mm THICK DENSE CEMENT CONCRETE SUBFLOOR

FLOOR FINISH

GL

Drawing not to Scale

Fig. 2.3(vi) : Anti-Termite Construction – Stage 6 CPWD SPECIFICATIONS 2009

58

ANTI-TERMITE CONSTRUCTION STAGE -7 Sub Head : Earthwork Clause : 2.28.3 (vii)

50 600

25 GL

100

50 DRY BRICK TAKEN OUT AND LIME CONCRETE BED (1:3:6) LAID FOR APRON FLOOR

Drawing not to Scale All dimensions in millimetres

Fig. 2.3(vii) : Anti-Termite Construction – Stage 7

ANTI-TERMITE CONSTRUCTION STAGE -8 Sub Head : Earthwork Clause : 2.28.3(viii)

12 mm THICK CEMENT PLASTER

25 mm THICK CEMENT CONCRETE (1:2:4) TOPPING

GL

Drawing not to Scale

Fig. 2.3(viii) : Anti-Termite Construction – Stage 8 59

SUB HEAD 2.0 : EARTH WORK

ANTI-TERMITE CONSTRUCTION FINAL RECOMMENDATIONS Sub Head : Earthwork Clause : 2.28.3(viii)(a)

SUPERSTRUCTURE FLOOR FINISH

75 mm THICK CEMENT CONCRETE SUBFLOOR

SAND FILLING

BRICK ON EDGE

75 100 12 mm THICK CEMENT PLASTER 50

600 25

100

GL

EARTH FILLING

50 LIME CONCRETE APRON CEMENT CONCRETE TOPPING

Drawing not to Scale All dimensions in millimetres

Fig. 2.4 : Anti-Termite Construction – Final Recommendations

CPWD SPECIFICATIONS 2009

60

SUB HEAD : 3.0

MORTARS

CONTENTS Clause No.

Brief Description List of Mandatory Tests

Page No. 65

List of Bureau of Indian Standard Codes

67

3.0

General

68

3.1

Materials

68

3.2

Preparation of Mortars & its Grade

74

Appendix A

Test for Organic Impurities

76

Appendix B

Test for Particle size (Sieve Analysis)

77

Appendix C

Test for Silt Content

78

Appendix D

Bulking of Fine Aggregates/ Sand (Field Methods)

79

Appendix E

Physical Requirements & Chemical Requirements of Fly Ash

80

Appendix F

Criteria for Selection of Masonry Mortars

81

63

SUB HEAD 3.0 : MORTARS

CPWD SPECIFICATIONS 2009

64

LIST OF MANDATORY TESTS Material Clause

1 Water

2 3.1.1

Cement 3.1.2

Sand

3.1.3.1

3.1.3.2 3.1.3.4

Test

3 (i) pH Value (ii) Limits of Acidity (iii) Limits of Alkality (iv) Percentage of solids (a) Chlorides (b) Suspended matter (c) Sulphates (d) Inorganic solids (e) Organic solids

Field/ laboratory test

4 Lab Lab

Test procedure

5 IS 3025

Min. quantity of material for carrying out the test 6 -

Lab Lab Lab Lab Lab Lab Lab

(a) Physical requirement (i) Fineness

Lab

(ii) Soundness

Lab

(iii) Setting time (Initial & Final) (iv) Compressive strength (v) Consistency of standard cement paste Organic impurities

Lab

Silt Content Particle size distribution a,b,c,d &e

Frequency of testing

7 Water from each source shall be got tested before the commencement of work and thereafter once in every three months till the completion of the work. Water from municipal source need be tested only once in six months. Number of Tests for each source shall be 3

IS 4031 (Part II) IS 4031 (Part III) IS 4031 (Part V) IS 4031 (Part VI) IS 4031 (Part VI)

Each lot

Every 50 tonnes or part thereof. Each brand of cement brought to site shall be tested as per this frequency.

Field

Appendix ‘A’

20 cum

Field Field or Laboratory as decided by the Engineer-incharge

Appendix C Appendix B

20 cum 40 cum

Every 20 cum or part thereof or more frequently as decided by Engineer-in-Charge. -do40 cum or part thereof

Lab Lab

65

SUB HEAD 3.0 : MORTARS

1 Sand

2 3.1.3.5

3 Bulking of Sand

Fly Ash

3.1.5 & 3.1.5.1

4 Field

5 Appendix D

6 20 cum

Total chloride in Lab percent by mass, max.

IS 12423

10 cum

Loss of ignition in Lab percent by mass, max. Fineness, specific Lab/field surface in m2/kg

IS 1727

10 cum

Blaine’s permeability method -

10 cum

-do-

10 cum

Only in cases when fly ash is used as pozzolana in cement

Compressive Lab. strength at 28 days in N/mm2, Min.

CPWD SPECIFICATIONS 2009

66

7 Every 20 cum or part thereof or more frequently as decided by Engineer-in-Charge. Every 10 cum or part thereof or more Frequency as decided by Engineer-in-charge

LIST OF BUREAU OF INDIAN STANDARD CODES S. No. 1 2

I.S. No. IS 269 IS 383

3 4 5 6 7 8 9 10 11 12

IS 455 IS 460 (Part I) IS 650 IS 1269 IS 1344 IS 1489 IS 1542 IS 1727 IS 2116 IS 2250

13

IS 2386 (Pt-I)

14

IS 2386 (Pt-II)

15

IS 2386 (Pt-III)

16 17 18

IS 3025 IS 3406 IS 3812 (Part I)

19

IS 3812 (Part II)

20

IS 4031 (Part I) to (Part XIII) IS 4032 IS 8041 IS 8042 IS 8043 IS 8112 IS 11652 IS 11653 IS 12174

21 22 23 24 25 26 27 28

Subject Specification for 33 grade ordinary Portland cement Specification for coarse and fine aggregate from natural source for concrete. Specification for Portland slag cement. Specification for test sieves: wire cloth test sieves. Specification for standard sand for testing of cement Specification for 53 grade ordinary Portland cement Specification for calcined clay Pozzolana. Specification for Portland pozzolana cement Specification for sand for plaster Methods of Test for Pozzolanic materials Specification for sand for masonry mortar. Code of practice for preparation and use of masonry Mortar. Method of test for aggregate for concrete (Particle size and shape) -Do- Estimation of deleterious materials and organic impurities. -Do- Specific gravity, density, voids, absorption and bulking. Method of sampling and test for water Specification for masonry cement. Specification for flyash for use as pozzolana in cement mortar and concrete Specification for flyash for use as admixture in cement martar and concrete Method of Physical test for hydraulic cement Method of chemical analysis of Hydraulic cement. Rapid hardening Portland cement. Specification for white cement Hydrophobic Portland cement Specification for 43 grade ordinary Portland cement Woven HDPE sacks for packing cement Woven polypropylene sacks for packing cement Jute synthetic union bags for packing cement

67

SUB HEAD 3.0 : MORTARS

3.0 MORTARS 3.0 GENERAL Desirable properties of mortars for use in masonry are: (a) Workability (b) Water retentivity (c) Rate of stiffing (d) Strength (e) Resistance to rain penetration (f) Durability 3.1 MATERIALS 3.1.1 Water 3.1.1.1 Water used for mixing and curing shall be clean and free from injurious quantities of alkalies, acids, oils, salts, sugar, organic materials, vegetable growth or other substance that may be deleterious to bricks, stone, concrete or steel. potable water is generally considered satisfactory for mixing. The Ph value of water shall be not less than 6. The following concentrations represent the maximum permissible values: (of deleterious materials in water). (a) Limits of Acidity: To neutralize 100ml sample of water, using phenolphthalein as an indicator, it should not require more than 5ml of 0.02 normal NaOH. The details of test shall be as given in IS 3025 (part 22). (b) Limits of Alkalinity: To neturalise 100ml sample of water, using mixed indicator, it should not require more than 25ml of 0.02 normal H2SO4. The details of tests shall be as given in IS 3025 (part 23). (c) Percentage of Solids: Maximum permissible limits of solids when tested in accordance with IS 3025 shall be as under: Organic 200mg/ litre Inorganic 3000 mg/ litre Sulphates 400 mg/ litre Chlorides 2000 mg/ litre.for concrete not containing embedded steel and 500 mg./ltr.for reinforced concrete work. Suspended matter 2000 mg/ litre The physical and chemical properties of ground water shall be tested along with soil investigation and if the water is not found conforming to the requirements of IS 456-2000, the tender documents shall clearly specify that the contractor has to arrange good quality water for construction indicating the source. 3.1.1.2 Water found satisfactory for mixing is also suitable for curing. However, water used for curing shall not produce any objectionable stain or unsightly deposit on the surface. 3.1.1.3 Sea water shall not be used for mixing or curing 3.1.1.4 Water from each source shall be tested before the commencement of the work and thereafter once in every three months till the completion of the work. In case of ground water, testing shall also be done for different points of drawdown. Water from each source shall be got tested during the dry season before monsoon and again after monsoon. 3.1.2 Cement 3.1.2.1 The cement used shall be any of the following grade and the type selected should be appropriate for the intended use. CPWD SPECIFICATIONS 2009

68

(a) (b) (c) (d) (e) (f) (g) (h) (i) (j) (k)

33 grade ordinary Portland cement conforming to IS 269. 43 grade ordinary Portland cement conforming to IS 8112. 53 grade ordinary Portland cement conforming to IS 12269. Rapid hardening Portland cement conforming to IS 8041. Portland slag cement conforming to IS 455. Portland Pozzolana cement (flyash based) conforming to IS 1489 (Part 1). Portland Pozzolona cement (calcined clay based) conforming to IS 1489 (part 2). Hydrophobic cement conforming to IS 8043 Low heat Portland cement conforming to IS 12600. Sulphate resisting Portland cement conforming to IS 12330 White cement conforming to IS 8042

Different types of cement shall not be mixed together. In case more than one type of cement is used in any work, a record shall be kept showing the location and the types of cement used. 3.1.2.2 Caution in Use of Cement Grade 53 in Construction: Because of the faster hydration process, the concrete releases heat of hydration at a much faster rate initially and release of heat is the higher in case of Grade. 53. The heat of hydration being higher, the chances of micro-cracking of concrete is much greater. Thus, during initial setting period of concrete, the higher heat of hydration can lead to damaging micro-cracking within the concrete which may not be visible at surface. This cracking is different from shrinkage cracks which occurs due to faster drying of concrete in windy conditions. The situation can be worse when we tend to increase the quantity of the cement in the concrete with a belief that such increases are better for both strength and durability of concrete. Thus, it is very essential to be forewarned that higher grade cement specially grade 53 should be used only where such use is warranted for making higher strength concrete and also where good Quality Assurance measures are in place, by which proper precaution are taken to relieve the higher heat of hydration through chilling of aggregates or by proper curing of concrete. There are instances where higher grade cement is being used even for low strength concrete, as, mortar or even for plastering. This can lead to unnecessary cracking of concrete/ surfaces. Another issue to be cautioned against is the tendency of the manufacturers to project Grade 53 cement as stronger cement, whereas Grade 33 or 43 are enough to produce the concrete of desired characteristic strength. The scenario of method of production of cement by various manufacturers should also be kept in mind while ordering various grades of cement. The ability to produce cements of particular fineness get fixed by the machinery installed by the manufacturers, and thus the ability to produce other various grades of cement by a particular manufacturer also gets limited. Whereas tendency today is to supply the consumer what he orders for by the manufacturers by simply stamping such grades on the bags. Thus, it is often observed that cement bags marked as grade 33 or 43 may really be containing cements of much higher grade. 3.1.2.3 Compressive Strength : Compressive strength requirement of each type of cement for various grades when tested in accordance with IS 4031 (part 6) shall be as under: Sample Age at testing 72 + 1 hr 168 + 2 hrs 672 + 4 hrs

Gr. 33 16 22 33

Strength in N/mm2 not less than for Gr.43 23 33 43

Gr. 53 27 37 53

3.1.2.4 Setting Time: Setting time of cement of any type of any grade when tested by Vicat apparatus method described in IS 4031 shall conform to the following requirement: 69

SUB HEAD 3.0 : MORTARS

(a) Initial setting time: Not less than 30 minutes (b) Final setting time: Not more than 600 minutes 3.1.2.5 Supply : The cement shall be packed in jute sacking bags conforming to IS 2580, double hessian bituminized (CRI type) or woven HDPE conforming to IS 11652. Woven polypropylene conforming to IS 11653, jute synthetic union conforming to IS: 12174, or any other approved composite bags, bearing the manufacturer’s name or his registered trade mark if any, with grade batch no. and type of cement, with date of manufacturing of batch of cement. Every delivery of cement shall be accompanied by a producer’s certificate conforming that the supplied cement conforms to relevant specifications. These certificates shall be endorsed to the Engineer-in-Charge for his record. Every consignment of cement must have identification marks on packages indicating date of manufacturing grade and type of cement batch no. etc. Cemnt brought to works shall not be more than 6 weeks old from the date of manufacture. Effective precautionary measures shall be taken to eliminate dust-nuisance during loading or transferring cement. 3.1.2.6 Stacking and Storage : Cement in bags shall be stored and stacked in a shed which is dry, leakproof and as moisture-proof as possible. Flooring of the shed shall consists of the two layers of dry bricks laid on well consolidated earth to avoid contact of cement bags with the floor. Stacking shall be done about 150 to 200 mm clear above the floor using wooden planks. Cement bags shall be stacked at least 450 mm clear off the walls and in rows of two bags leaving in a space of atleast 600 mm between two consecutive rows. In each row the cement bags shall be kept close together so as to reduce air circulation. Stacking shall not be more than 10 bags high to avoid lumping under pressure. In stacks more than 8 bags high, the cement bags shall be arranged in header and stretcher fashion i.e. alternately lengthwise and crosswise so as to tie the stacks together and minimise the danger of toppling over. A typical arrangement for storing and stacking of cement is shown in Fig. 1. of sub-head of Carriage of Materials. Different types of cement shall be stacked and stored separately. Cement bags shall be stacked in a manner to facilitate their removal and use in the order in which they are received. For extra safety during monsoon, or when cement is expected to be stored for an unusually long period, each stack shall be completely enclosed by a water proofing membrane, such as polyethylene, which shall cover the top of the stack. Care shall be taken to see that the water proofing membrane is not damaged at any time during use. Storage of cement at the work site shall be at the contractor’s expense and risk. Any damage occurring to cement due to faulty storage in contractor’s shed or on account of negligence on his part shall be the liability of the contractor. 3.1.3 Fine Aggregate 3.1.3.1 Aggregate most of which passes through 4.75 mm IS sieve is known as fine aggregate. Fine aggregate shall consist of natural sand, crushed stone sand, crushed gravel sand stone dust or marble dust, fly ash and broken brick (Burnt clay). It shall be hard, durable, chemically inert, clean and free from adherent coatings, organic matter etc. and shall not contain any appreciable amount of clay balls or CPWD SPECIFICATIONS 2009

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pellets and harmful impurities e.g. iron pyrites, alkalies, salts, coal, mica, shale or similar laminated materials in such form or in such quantities as to cause corrosion of metal or affect adversely the hardening, the strength, the durability or the appearance of mortar, plaster or concrete. The sum of the percentages of all deleterious material shall not exceed 5%. Fine aggregate must be checked for organic impurities such as decayed vegetation humps, coal dust etc. in accordance with the procedure prescribed in Appendix ‘A’ of Chapter 3. 3.1.3.2 Silt Content : The maximum quantity of silt in sand as determined by the method prescribed in Appendix ‘C’ of Chapter 3 shall not exceed 8%. Fine aggregate containing more than allowable percentage of silt shall be washed as many times as directed by Engineer-in-charge so as to bring the silt content within allowable limits for which nothing extra shall be paid. 3.1.3.3 Grading : On the basis of particle size, fine aggregate is graded in to four zones. The grading when determined in accordance with the procedure prescribed in Appendix ‘B’ of Chapter 3 shall be within the limits given in Table 3.1 below. Where the grading falls outside the limits of any particular grading zone of sieves, other than 600 micron IS sieve, by a total amount not exceeding 5 per cent, it shall be regarded as falling within that grading zone. TABLE 3.1 Fine Aggregates (Clause 3.1.3 ) IS Sieve 10 mm 4.75 mm 2.36 mm 1.18 mm 600 microns 300 microns 150 microns Note 1:

Note 2: Note 3:

Note 4:

Grading Zone I 100 90-100 60-95 30-70 15-34 5-20 0-10

Percentage passing for Grading Zone II Grading Zone III 100 100 90-100 90-100 75-100 85-100 55-90 75-100 35-59 60-79 8-30 12-40 0-10 0-10

Grading Zone IV 100 95-100 95-100 90-100 80-100 15-50 0-15

For crushed stone sands, the permissible limit on 150 micron sieve is increased to 20 per cent. This does not affect the 5 per cent allowance permitted in 3.1.3.4 (e) (1) applying to other sieves. Allowance of 5% permitted in 3.1.3.4 (e) (1) can be split up, for example it could be 1% on each of three sieves and 2% on another or 4% on one sieve and 1% on another. Fine aggregate conforming to Grading Zone IV shall not be used in reinforced cement concrete unless tests have been made to ascertain the suitability of proposed mix proportions. Sand requiring use for mortar for plaster work shall conform to IS 1542 and for masonry work shall conform to IS 2116.

3.1.3.4 Type and grading of fine aggregate to be used shall be specified. It shall be coarse sand, fine sand, stone dust or marble dust, fly ash and surkhi. Use of sea sand shall not be allowed, unless otherwise specified. (a) Coarse sand shall be either river sand or pit sand or a combination of the two. Badarpur sand available in Delhi generally falls in category of pit sand. It shall be clean, sharp, angular, gritty to touch and composed of hard silicious material. Its grading shall fall within the limits of grading zone I, II, III of Table 3.1. Grading of sand shall conform to IS 2116 for use in Masonry work. 71

SUB HEAD 3.0 : MORTARS

(b) Fine sand shall be either river sand or pit sand or a combination of the two. Its grading shall fall within the limits of Grading zone IV of Table 3.1. As a guideline, fine sand conforming to grading Zone IV can be generally obtained in Delhi by mixing one part of Badarpur sand and two parts of jamuna Sand (by volume). Grading of sand shall conform to IS 1542 for use in plaster work. (c) Stone dust shall be obtained by crushing hard stones or gravel. Its grading shall fall within the limits of grading Zone, I, II, or III of Table 3.1. (d) Marble dust shall be obtained by crushing marble. Its grading shall fall within the limits of Grading Zone IV of Table 3.1. Grading of Marble dust for use in Mortar shall be as per following table. Grading of Marble Dust IS Sieve 10 mm 4.75 mm 2.36 mm 1.18 mm 600 micron 300 micron 150 micron

Percentage Passing 100 95-100 95-100 90-100 80-100 15-50 0-15

(e) Sand for Masonry Mortar and for Plaster- Sand shall consist of natural sand, crushed stone sand or crushed gravel sand or a combination of any of these. Sand shall be hard durable, clean and free from adherent coating and organic matter and shall not contain the amount of clay, silt and fine dust more than specified as under. Deleterious Material: Sand shall not contain any harmful impurities such as iron, pyrites, alkalis, salts, coal or other organic impurities, mica, shale or similar laminated materials, soft fragments, sea shale in such form or in such quantities as to affect adversely the hardening, strength or durability of the mortar. The maximum quantities of clay, fine silt, fine dust and organic impurities in the sand / Marble dust shall not exceed the following limits: (1)

(2)

Clay, fine silt and fine dust when Not more than 5% by mass determined in accordance within IS 2386 (Part II). In natural sand or crushed gravel sand & crushed stone sand Organic impurities when determined in Colour of the liquid shall be lighter than accordance with IS 2386 (Part II) that indicated by the standard specified in IS 2386 (Part II).

Grading of sand for use in masonry mortar shall be conforming to IS 216 (Table 3.2 below). Grading of sand for use in plaster shall be conforming to IS 1542 (Table 3.2 below): TABLE 3.2 Grading of Sand for use in Masonry Mortar and Plaster Grading of sand for use in masonry mortar IS Sieve Designation Pecentage passing by mass 10 mm 100 4.75 mm 100 2.36 mm 90 to 100 CPWD SPECIFICATIONS 2009

Grading of sand for use in plaster IS Sieve Designation Pecentage passing by mass 10 mm 100 4.75 mm 95 to 100 2.36 mm 95 to 100 72

Grading of sand for use in masonry mortar IS Sieve Designation Pecentage passing by mass 1.18 mm 70 to 100 600 micron 40 to 100 300 micron 5 to 70 150 micron 0 to 15

Grading of sand for use in plaster IS Sieve Designation Pecentage passing by mass 1.18 mm 90 to 100 600 micron 80 to 100 300 micron 20 to 65 150 micron 0 to 50

Note: For crushed stone sands, the permissible limit on 150 micron IS Sieve is increased to 20%, this does not affect the 5% allowance as per IS 2386 (Part 1). 3.1.3.5 Bulking: Fine aggregate, when dry or saturated, has almost the same Volume but dampness causes increase in volume. In case fine aggregate is damp at the time of proportioning the ingredients for mortar or concrete, its quantity shall be increased suitably to allow for bulkage, which shall be determined by the method prescribed in Appendix ‘D’ of Chapter 3.0 Table 3.3 gives the relation between moisture content and percentage of bulking for guidance only. TABLE 3.3 Moisture content % age 2 3 4 5

Bulking % age (by volume) 15 20 25 30

3.1.3.6 Stacking: Fine aggregate shall be so stacked as to prevent dust and foreign matter getting mixed up with it as far as practically possible. Marble dust in dry condition shall be collected in bags and properly staked so as not to form lumps, suitable arrangements shall be made to protect it from moisture similar to those adopted for stacking of cement bags. 3.1.3.7 Measurements: As the fine aggregate bulks to a substantial extent when partially wet, measurements shall be taken when the stacks are dry or appropriate allowance made for bulking. 3.1.4 Broken Brick (Burnt Clay) Fine Aggregate 3.1.4.1 Broken Brick (Burnt Clay) Fine Aggregate, also known as Surkhi, shall be made by grinding well burnt (but not under or over burnt) broken bricks as specified in IS 3068-1986. It shall not contain any harmful impurities, such as iron pyrites, salts, coal, mica, shale or similar laminated or other materials in such form of quantity as to adversely affect hardening, strength, durability or appearance of the mortar. The maximum quantities of clay, fine silt, fine dust and organic impurities in surkhi (all taken together) shall not exceed five per cent by weight. The particle size grading of surkhi for use in lime mortars shall be within the limits specified in Table 3.4. TABLE 3.4 IS Sieve Designation 4.75 mm 2.36 mm 1.18 mm 600 microns 300 microns 150 microns

Percentage passing (by wt) 100 90-100 70-100 40-100 5-70 0-15

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3.1.4.2 Stacking: Surkhi shall be stacked on a hard surface or platform so as to prevent the admixture of clay, dust, vegetation and other foreign matter. It shall be also protected form rain and dampness and kept under adequate coverings. 3.1.4.3 Measurements: Surkhi shall be measured in regular stacks in cubic metres. Alternatively it may be measured by weight when supplied in bags. 3.1.5 Fly Ash Fly ash is finely divided residue resulting from the combustion of pulverized coal in boilers. Fly ash is the pulverized fuel ash extracted from the flue gases by any suitable process such as cyclone separation or electrostatic precipitation. The ash collected from the bottom of boilers is termed as bottom ash. Fly ash is finer than bottom ash. Siliceous fly ash (ASTM Class F) containing calcium oxide less than 10% by mass is normally produced from burning anthracite or bituminous coal and possesses pozzolanic properties. Calcareous fly ash (ASTM Class C) is poruduced by burning lignite or sub-bituminous coal and contains calcium exide more than 10% by mass; the content could be as high as 25%. This fly ash has both hydraulic and pozzolanic properties. It shall be clean and free from any contamination of bottom ash, grit or small pieces of pebbles. It is obligatory on the part of supplier/ manufacture that the fly ash conforms to the requirements if mutually agreed upon & shall furnish a certificate to this effect to the purchaser or his representative. 3.1.5.1 Characteristics: The physical requirements of fly-ash shall be as specified in Annexure ‘E’ of Chapter 3. The chemical properties of fly ash shall be as per IS 3812 (part 1 & 2) depending on the usage. 3.1.5.2 Stacking: Fly ash shall be protected from dirt collecting on it. 3.1.5.3 Measurements: Fly ash shall be measured in regular stacks in cubic metres. Alternatively it may be measured by weight when supplied in bags. 3.2 PREPARTATION OF MORTARS AND ITS GRADE 3.2.0 Grade of Masonry Mortar The grade of masonry mortar will be defined by its compressive strength in N/mm2 at the age of 28 days as determined by the standard procedure detailed in IS 2250. 3.2.0.1 For proportioning the ingredients by volume, the conversion of weight into volume shall be made on the following basis: (a) (b) (c) (d)

Burnt Clay Pozzolana Coarse Sand (dry) Fine sand (dry) Fly Ash

860 Kg/cum 1280 kg/cum 1600 kg/ cum 590 kg/ cum

For details of grades and criteria for selection of Masonry mortars see Appendix ‘F’ of chapter-3. 3.2.1 Cement Mortar 3.2.1.1 This shall be prepared by mixing cement and sand with or without the addition of pozzolana in specified proportions as per Appendix ‘F’. 3.2.1.2 Proportioning: Proportioning on weight basis shall be preferred taking into account specific gravity of sand and moisture content . Boxes of suitable size shall be prepared to facilitate proportioning on weight basis. Cement bag weighting 50 kg shall be taken as 0.035 cubic metre. Other ingredients in specified proportion shall be measured using boxes of size 40 x 35 x 25 cm. Sand shall be measured on the basis of its dry volume in the case of volumetric proportioning. CPWD SPECIFICATIONS 2009

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3.2.1.3 Mixing 3.2.1.3.1 The mixing of mortar shall be done in mechanical mixers operated manually or by power as decided by Engineer-in-Charge. The Engineer-in-Charge may, however, permit hand mixing at his discretion taking into account the nature, magnitude and location of the work and practicability of the use of mechanical mixers or where item involving small quantities are to be done or if in his opinion the use of mechanical mixer is not feasible. In cases, where mechanical mixers are not to be used, The contractor shall take permission of the Engineer-in-Charge in writing before the commencement of the work. (a) Mechanical Mixing: Cement and sand in the specified proportions shall be mixed dry thoroughly in a mixer. Water shall then be added gradually and wet mixing continued for at least three minutes. only the required quantity of water shall be added which will produce mortar of workable consistency but not stiff paste. Only the quantity of mortar, which can be used within 30 minutes of its mixing shall be prepared at a time. Mixer shall be cleaned with water each time before suspending the work. (b) Hand Mixing: The measured quantity of sand shall be leveled on a clean masonry platform and cement bags emptied on top. The cement and sand shall be thoroughly mixed dry by being turned over and over, backwards and forwards, several times till the mixture is of a uniform colour. The quantity of dry mix which can be used within 30 minutes shall then be mixed in a masonry trough with just sufficient quantity of water to bring the mortar to a stiff paste of necessary working consistency. 3.2.1.4 Precautions: mortar shall be used as soon as possible after mixing and before it begins to set, and in any case within half hour, after the water is added to the dry mixture. 3.2.2 Cement Flyash Sand Mortar 3.2.2.1 This shall be prepared by mixing cement, flyash and sand in specified proportions as per Appendix G. Mixing shall be done in a mechanical mixer (operated manually or by power) unless otherwise permitted by the Engineer-in-Charge in writing. The Engineer-in-Charge may, however, permit hand mixing at his discretion, taking into account the nature, magnitude and location of the work and practicability of the use of mechanical mixer or where items involving small quantities are to be done or if in his opinion the use of mechanical mixer is not feasible. In case, where mechanical mixer is not to be used, the contractor shall take permission of the Engineer-in-Charge in writing before the commencement of the work. 3.2.2.2 Proportioning: Proportioning on weight basis shall be preferred taking into account specific gravity of Fly Ash, sand and moisture content. Boxes of suitable size shall be prepared to facilitate proportioning on weight basis. Cement bag weighting 50 kg shall be taken as 0.035 cubic metre. Other ingredients in the specified proportions shall be measured using boxes of suitable sizes. Sand and flyash shall be measured on the basis of their dry volume in the case of volumetric proportioning. 3.2.2.3 Mixing (a) Mechanical Mixing: Sand and flyash in the specified proportions shall be mixed dry in a mixer and then the specified quantity of cement shall be added and mixed dry thoroughly. Water shall then be added gradually and wet mixing continued for atleast one minute. Water shall be just sufficient to bring the mortar to the consistency of a workable paste. Only the quantity of mortar which can be used within 30 minutes of its mixing shall be prepared at a time. (b) Hand Mixing: The measured quantity of sand and flyash shall be mixed dry on a clean masonry platform before adding specified quantity of cement to it. The resulting mixture of cement, sand and flyash shall then be mixed thoroughly being turned over and over, backward several times till the mixture is of a uniform colour. The quantity of dry mix which can be used within 30 minutes shall then be mixed in a clean watertight masonry trough with just sufficient quantity of water, to bring the mortar to a stiff paste of necessary working consistency. 3.2.2.4 Precautions: Shall be same as specified in 3.2.1.4. 75

SUB HEAD 3.0 : MORTARS

APPENDIX ‘A’

TEST FOR ORGANIC IMPURITIES (Clause 3.1.3.1)

The aggregate must also be checked for organic impurities such as decayed vegetation humus, coal dust etc. What is called the colour test is reliable indicator of the presence of harmful organic matter in aggregate, except in the area where there are deposits of lignite. Fill a 350 ml clear glass medicine bottle upto 70 ml mark with a 3% solution of caustic soda or sodium hydroxide. The sand is next added gradually until the volume measured by the sandy layer is 125 ml. The volume is then made upto 200 ml by addition of more of solution. The bottle is then stoppered and shaken vigorously and allowed to stand for 24 hours. At the end of this period, the colour of the liquid will indicate whether the sand contains a dangerous amount of matter. A colourless liquid indicates a clean sand free from organic matter. A straw coloured solution indicates some organic matter but not enough to be seriously objectionable. Darker colour means that the sand contains injurious amounts and should not be used unless it is washed, and a retest shows that it is satisfactory. Add 2.5 ml of two per cent solution of tannic acid in 10 per cent alcohol, to 97.5 ml of three per cent sodium hydroxide solution. Place in a 350 ml bottle, fix the stopper, shake vigorously and allow to stand for 24 hours before comparison with the solution above the sand. Note: A three per cent solution of caustic soda is made by dissolving 3 g of sodium hydroxide in 100 ml of water, preferably distilled. The solution should be kept in a glass of bottle tightly closed with a rubber stopper. Handling sodium hydroxide with moist hands may result in serious burns. Care should be taken not to spill the solution for it is highly injurious to clothing, leather, and other materials.

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APPENDIX ‘B’

TEST FOR PARTICLE SIZE (SIEVE ANALYSIS) (Clause 3.1.3.3) Apparatus: Perforated plate sieves of designation 10 mm, 4.75 mm and fine mesh sieve of designation 2.36 mm, 1.18 mm, 600 micron, 300 micron and 150 micron should be used. The balance or scale shall be such that it is readable and accurate to 0.1 per cent of the weight of the test sample. Sample: The weight of sample available shall not be less than the weight given in the table below. The sample of sieving shall be prepared from the larger sample either by quartering or by means of a sample divider. TABLE SHOWING MINIMUM WEIGHTS FOR SAMPLING Maximum size present in Minimum weight of sample for substantial proportions (mm) sieving (Kg) 10 0.5 4.75 0.2 2.36 0.1 Test Procedure: The sample shall be brought to an air-dry condition before weighing and sieving. This may be achieved either by drying at room temperature or by heating at a temperature of 100 degree to 110 degree centigrade. The air dry sample shall be weighed and sieved successively on the appropriate sieves starting with the largest. Care shall be taken to ensure that the sieves are clean before use. Each sieve shall be shaken separately over a clean tray until not more than a trace passes, but in any case for a period of not less than two minutes. The shaking shall be done with a varied motion, backwards and forwards, left to right, circular clockwise and anti-clockwise, and with frequent jarring, so that the material is kept moving over the sieve surface in frequently changing directions. Materials shall not be forced through the sieve by hand pressure, but on sieves coarser than 20 mm, placing of particles is permitted, Lumps of fine material, if present may be broken by gentle pressure with fingers against the side of the sieve. Light brushing of under side of the sieve with a soft brush may be used to clear the sieve openings. Light brushing with a fine camel hair brush may be used on the 150 micron IS sieve to prevent segregation of powder and blinding of apertures. Stiff or worn out brushes shall not be used for this purpose and pressure shall not be applied to the surface of the sieve to force particles through the mesh. On completion of sieving the material retained on each sieve, together with any material cleaned from the mesh, shall be weighed. Reporting of Results: The results shall be calculated and reported as: (a) The cumulative percentage by weight of the total sample passing each of the sieves, to the nearest whole number: or (b) The percentage by weight of the total sample passing one sieve and retained on the next smaller sieve, to the nearest 0.1 percent.

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APPENDIX ‘C’

TEST FOR SILT CONTENT (Clause 3.1.3.2) The sand shall not contain more than 8% of silt as determined by field test with measuring cylinder. The method of determining silt contents by field test is given below: A sample of sand to be tested shall be placed without drying in a 200 ml measuring cylinder. The volume of the sample shall be such that it fills the cylinder upto 100 ml mark Clean water shall be added upto 150 ml mark. Dissolve a little salt in the water in the proportion one tea spoon to half a litre. The mixture shall be shaken vigorously, the last few shakes being sidewise direction to level off the sand and the contents allowed to settle for three hours. The height of the silt visible as settled layer above the sand shall be expressed as a percentage of the height of sand below. The sand containing more than the above allowable percentage of silt, shall be washed so as to bring the silt contents within allowable limits.

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APPENDIX ‘D’

BULKING OF FINE AGGREGATES/SAND (FIELD METHODS) (Clause 3.1.3.5) Two methods are suggested for determining the bulking of sand/fine aggregate. The procedure may be suitably varied, if necessary. Both depend on the fact that the volume of inundated sand/fine aggregate is the same if the sand/fine aggregate were dry. Method -1: Put sufficient quantity of sand loosely into a container until it is about two-third full. Level off the top of the sand and push a steel rule vertically down through the sand at the middle to bottom, measure the height. Suppose this is ‘X’ cm. Empty the sand out of the container into another container where none of it is lost. Half fill the first container with water. Put back about half the sand and rod it with a steel rod, about 6 mm in diameter, so that its volume is reduced to a minimum. Then add the remainder and level the top surface of the inundated sand. Measure its depth at the middle with the steel rule. Suppose this is ‘Y’ cm. The percentage of bulking of the sand due to moisture shall be calculated from the formula: Percentage bulking = (X/Y -1) X 100 Method-2: In a 250 ml measuring cylinder, pour the damp sand, consolidate it by staking until it reached the 200 ml mark. Then fill the cylinder with the water and stir the sand well (the water shall be sufficient to submerge the sand completely). It will be seen that the sand surface is now below its original level. Suppose the surface is at the mark of Yml, the percentage of bulking of sand due to moisture shall be calculated from the formula. Percentage bulking= (200/Y – 1) x 100

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APPENDIX ‘E’

PHYSICAL REQUIREMENTS OF FLY ASH (Clause 3.1.5 & 3.1.5.1) Sl. No

Characteristics

Requirement of Fly Ash For use as Pozzolana

1 (i) (ii) (iii)

(iv) (v)

2 Fineness- Specific surface in m2/kg by Blaine’s permeability method, min Lime reactivity – average compressive strength in N/mm2 Min Compressive strength at 28 days in N/ mm2

Soundness of autoclave test expansion of specimens, per cent, max Particles retained on 45 micron IS sieve (wet sieving) in percent maximum

CPWD SPECIFICATIONS 2009

80

3 320

For use as admixture in Cement Mortar and concrete 4 200

4.5

-

Not less than 80 per cent of the strength of corresponding mortar cubes. 0.8

-

0.8

34

50

APPENDIX ‘F’

CRITERIA FOR SELECTION OF MASONRY MORTARS (Clauses 3.2.0, 3.2.0.1, 3.2.1.1) (a) The selection of masonry mortars from durability consideration will have to cover both the loading and exposure condition of the masonry. The masonry mortar shall generally be as specified below in (b) to (g). (b) In case of masonry exposed frequent to rain and where there is further protection by way of plastering or rendering or other finishes, the grade of mortar shall not be less than 0.7 MM but shall preferably be of grade MM2. Where no protection is provided, the grade of mortar for external wall shall not be less than MM2. (c) In case of load bearing internal walls, the grade of mortar shall preferably be MM 0.702 or more for high durability but in no case less than MM 0.5. (d) In the case of masonry work in foundations laid below damp proof course, the grade of mortar for use in masonry shall be as specified below. (i) Where soil has little moisture, masonry mortar of grade not less than MM 0.7 shall be used. (ii) Where soil is very damp, masonry mortar of grade preferably MM 2 or more shall be used. But in no case shall the grade of mortar be less than MM 2. (e) For masonry in building subject to vibration of machinery, the grade of mortar shall not be less than MM 3. (f) For parapets, where the height is greater than thrice the thickness, the grade of masonry mortar shall not be less than MM3. In case of low parapets the grade of mortar shall be the same as used in the wall masonry. (g) The grade of mortar for bedding joints in masonry with large concrete blocks shall not be less than MM 3. (h) The compressive strength shall be determined in accordance with the procedure given in IS 2250. (i) While mixing the pozzolanic material like fly ash in mortars Ordinary Portland cement only shall be use. Grade of Masonry Mortar (IS 2250 ) (Clause 3.2.0) Sl. No.

Grade

1 2

MM 0.7

Compressive strength at 28 days in N/mm2 0.7 to 1.5

Cement 1 1

Pozzolana (Fly Ash) --0.4*

Sand 8 10

3 MM 1.5 1.5 to 2.0 1 --7 4 1 0.4* 8.75 5 MM 3 3.0 to 5.0 1 ---6 6 1** 0.21 4.2 7 1 0.4* 7.5 8 MM 5 5.0 to 7.5 1 ---5 9 1 0.4 6.25 10 1 0.4 5 11 MM 7.5 7.5 & above 1 ---4 12 1** 0.2* 2.1 13 1 --3 14 1 0.4 3.75 Note: * Pozzolana of minimum lime reactivity of 4 N/MM2 ** This ratio by volume correspondence approximately to cement pozzolana ratio of 0.8:0.2 by weight. In this case, only ordinary portland cement is to be used (see IS 269). Specifications for ordinary rapid hardening and low heat Portland Cement (Third revision). Note : Compressive strength shall be determined in accordance with the Appendix –A-IS 2550. 81

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82

SUB HEAD : 4.0

CONCRETE WORK

CONTENTS Clause No.

Brief Description List of Mandatory Tests

Page No. 87

List of Bureau of Indian Standard Codes

88

4.1 4.1.1 4.1.2

Material Coarse Aggregate Chemical Admixtures

89 89 91

4.2 4.2.1 4.2.2 4.2.3 4.2.4 4.2.5 4.2.6 4.2.7 4.2.8 4.2.9 4.2.10 4.2.11 4.2.12 4.2.13 4.2.14 4.2.15 4.2.16

Cement Concrete Grades of Cement Concrete Workability of Concrete Concrete Mix Proportioning Batching Mixing Placing Compaction Construction Joints Concreting under Special Conditions Curing Testing of Concrete Form Work Finishes Durability of Concrete Measurements Rate

92 92 94 95 95 97 99 99 99 99 100 101 101 101 101 104 106

4.3

Cement Fly Ash Concrete

106

4.4 4.4.1 4.4.2 4.4.3 4.4.4 4.4.5 4.4.6

Damp Proof Course Cement Concrete Layer Curing Application of Hot Bitumen Water Proofing Materials Measurements Rate

107 107 107 107 107 107 107

Appendix A

Determination of Particle Size

108

Appendix B

Test for Surface Moisture

108

Appendix C

Determination of Ten Per cent Fine Value

109

Appendix D

Slump Test

111

85

SUB HEAD 4.0 : CONCRETE WORK

CPWD SPECIFICATIONS 2009

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LIST OF MANDATORY TESTS Material

1

Clause Test

2

Stone 4.1.2.2 aggregate

Concrete

Field/ Laboratory

3

4

Test procedure

Min. qty of Frequency Material for of Testing Carrying out test

5

6

7

(a) Percentage of soft or deleterious material

Field or LaboratoryTest as required

IS 2386- As required For all Part II by Engineer- quantities in-charge

4.1.2.3

Particle size

Field/ Lab

Appendix ‘A’ 45 cum

For every 45 cum or part thereof for RCC Work only. For rest of items as decided by Engineer-incharge

4.1.2.5

(a) Estimation of organic impurities (b) Surface moisture (c) Determination of 10% fine value

Field/ Lab

IS 2386Part II

10 cum

Field/ Lab

IS 2386

10 cum

For every 40 cum or part thereof -do-

Field/ Lab

IS 2386

10 cum

-do-

(d) Specific gravity

Field/ Lab

IS 2386

10 cum

-do-

(e) Bulk density

Field/ Lab

IS 2386

10 cum

-do-

(f) Aggregate crusing Field/ Lab strength

IS 2386

10 cum

-do-

(g) Aggregate impact Field/ Lab value

IS 2386

10 cum

-do-

Slump test

Appendix ‘D’ 10 cum

4.2.2

Field

87

15 cum or part thereof

SUB HEAD 4.0 : CONCRETE WORK

LIST OF BUREAU OF INDIAN STANDARDS CODES S. No. I. S. No.

Subject

1.

IS 383

Specification for coarse and fine aggregate from natural sources for concrete.

2.

IS 456

Plain and reinforced concrete - Code of practice

3.

IS 516

Method of test for strength of concrete

4.

IS 1199

Method of sampling and analysis of concrete

5.

IS 1200 Method of measurement of building and civil engineering work (concrete (Part II) work)

6.

IS 1322

Specification for bitumen felt for water proofing and damp proofing.

7.

IS 1791

General requirements for batch type conrete mixers

8.

IS 2386

Method of test for aggregates for concrete (a) Part I - Particle size and shape (b) Part II - Estimation of deleterious materials and organic impurities (c) Part III - Specific gravity, density, voids absorption and bulking. (d) Part IV - Mechanical properties. (e) Part V – Soundness

9.

IS 2505

General requirements for concrete vibrators - immersion type.

10.

IS 2506

General requirements for concrete vibrators - screed board concrete vibrators

11.

IS 2645

Specification for integral water proofing compounds for cement mortar and concrete

12.

IS 3068

Specification for broken brick (burnt clay) coarse aggregate for use in concrete.

13.

IS 3812

Specification for flyash for use as pozzolana and admixture in cement mortar and concrete.

14.

IS 4656

Specification for form vibrators for concrete.

15.

IS 7861 Code of practice for extreme weather concreting (Part-I) recommended (Part-I) practice for hot weather concreting.

16.

IS 7861 Code of practice for extreme weather concreting (Part-II) recommended. (Part–II)

17.

IS 9103

Specification for concrete admixtures

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4.0 CONCRETE WORK 4.1. MATERIAL Water, cement, fine aggregate or sand, surkhi, and fly ash shall be as specified in Chapter 3.0 – Mortar. 4.1.1 Coarse Aggregate 4.1.1.1 General: Aggregate most of which is retained on 4.75 mm IS Sieve and contains only as much fine material as is permitted in IS 383 for various sizes and grading is known as coarse aggregate. Coarse aggregate shall be specified as stone aggregate, gravel or brick aggregate and it shall be obtained from approved/ authorized sources. (a) Stone Aggregate: It shall consist of naturally occurring (uncrushed, crushed or broken) stones. It shall be hard, strong, dense, durable and clean. It shall be free from veins, adherent coating, injurious amounts of disintegrated pieces, alkali, vegetable matter and other deleterious substances. It shall be roughly cubical in shape. Flaky and elongated pieces shall be avoided. It shall conform to IS 383 unless otherwise specified. (b) Gravel: It shall consist of naturally occurring (uncrushed, crushed or broken) river bed shingle or pit gravel. It shall be sound, hard and clean. It shall be free from flat particles of shale or similar laminated material, powdered clay, silt, loam, adherent coating, alkali, vegetable matter and other deleterious substances. Pit gravel shall be washed if it contains soil materials adhering to it. These shall conform to IS 383 unless otherwise specified. (c) Brick Aggregate: Brick aggregate shall be obtained by breaking well burnt or overburnt dense brick/ brick bats. They shall be homogeneous in texture, roughly cubical in shape and clean. They shall be free from unburnt clay particles. Soluble salt, silt, adherent coating of soil, vegetable matter and other deleterious substances. Such aggregate should not contain more than one percent of sulphates and should not absorb more than 10% of their own mass of water, when used in cement concrete. It shall conform to IS 306 unless otherwise specified. (d) Light weight aggregate such as sintered fly ash aggregate may also be used provided the Engineer-in-Charge is satisfied with the data on the proportion of concrete made with them. 4.1.1.2 Deleterious Material: Coarse aggregate shall not contain any deleterious material, such as pyrites, coal, lignite, mica, shale or similar laminated material, clay, alkali, soft fragments, sea shells and organic impurities in such quantity as to affect the strength or durability of the concrete. Coarse aggregate to be used for reinforced cement concrete. Coarse aggregate to be used for reinforced cement concrete shall not contain any material liable to attack the steel reinforcement. Aggregates which are chemically reactive with alkalies of cement shall not be used. The maximum quantity of deleterious material shall not be more than five percent of the weight of coarse aggregate when determined in accordance with IS 2386. 4.1.1.3 Size and Grading (i) Stone aggregate and gravel: It shall be either graded or single sized as specified. Nominal size and grading shall be as under:(a) Nominal sizes of graded stone aggregate or gravel shall be 40, 20, 16, or 12.5 mm as specified. For any one of the nominal sizes, the proportion of other sizes as determined by the method prescribed in Appendix ‘A’ of Chapter 4 shall be in accordance with Table 4.1.

89

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TABLE 4.1 Graded Stone Aggregate or Gravel IS Sieve Designation 80 mm 63 mm 40 mm 20 mm 16 mm 12.5 mm 10 mm 4.75 mm

40 mm 100 95 to 100 30 to 70 10 to 35 0 to 5

Percentage passing (by weight) for nominal size of 20 mm 16 mm 12.5 mm 100 95 to 100 100 100 90 to 100 90 to 100 25 to 55 30 to 70 40 to 85 0 to 10 0 to 10 0 to 10

(b) Nominal sizes of single sized stone aggregate or gravel shall be 63, 40, 20, 16, 12.5 or 10 mm as specified. For any one of the nominal size, the proportion of other sizes as determined by the method prescribed in Appendix ‘A’ of Chapter 4 shall be in accordance with Table 4.2. TABLE 4.2 Single Sized (Ungraded) Stone Aggregate or Gravel IS Sieve Designation 80 mm 63 mm 40 mm 20 mm 16 mm 12.5 mm 10 mm 4.75 mm 2.36 mm

63 mm 100 85-100 0-30 0- 5 0-5 -

Percentage passing (by weight) for nominal size of 40 mm 20 mm 16 mm 12.5 mm 100 85-100 100 0-20 85-100 100 85-100 100 85-100 0-5 0-20 0-30 0-45 0-5 0-5 0-10 -

10 mm 100 85-100 0-20 0-5

(c) When stone aggregate or gravel brought to site is single sized (ungraded), it shall be mixed with single sized aggregate of different sizes in the proportion to be determined by field tests to obtain graded aggregate of specified nominal size. For the required nominal size, the proportion of other sizes in mixed aggregate as determined by method prescribed in Appendix ‘A’ of Chapter 4 shall be in accordance with Table 4.1. Recommended proportions by volume for mixing of different sizes of single size (ungraded) aggregate to obtain the required nominal size of graded aggregate are given in Table 4.3. TABLE 4.3 Single Sized (Ungraded) Stone Aggregate or Gravel Cement concrete

(1) 1:6:12 1:6:12 1:5:10 CPWD SPECIFICATIONS 2009

Nominal size of graded aggregate required (2) 63 40 63

50 mm

Parts of single size aggregate of size 40 mm 20 mm 12.5 mm 10 mm

(3) 9 7.5 90

(4) 9 -

(5) 3 3 2.5

(6) -

(7) -

(1) (2) (3) (4) (5) (6) (7) 1:5:10 40 7.5 2.5 1:4:8 63 6 2 1:4:8 40 6 2 1:3:6 63 4.5 1.5 1:3:6 40 4.5 1.5 1:3:6 20 4.5 1.5 1:2:4 40 2.5 1 1.5 1:2:4 20 3 1 1:2:4 12.5 3 1 1 1: 1 /2 :3 20 0 0 2 1 Note: (i) The proportions indicated in Table 4.3 above are by volume when considered necessary, these proportions may be varied marginally by Engineer-in-Charge after making sieve analysis of aggregate brought to site for obtaining required graded aggregate. No adjustments in rate shall be made for any variation in the proportions so ordered by the Engineer-in-Charge. If single size coarse aggregate are not premixed at site to obtain the graded coarse aggregate required for the mix, the volume of single size aggregates required for the mix shall be suitably increased to account for reduction in total volume at the site of mixing. (ii) Brick Aggregate: Nominal size of brick aggregate shall be 40 mm and its grading shall be as specified in Table 4.4 when tested for sieve analysis for the method prescribed in Appendix ‘A’ of Chapter 4.0. TABLE 4.4 Brick Aggregate IS Sieve Designation 75 mm 37.5 mm 20.0 mm 4.75 mm

Percentage passing (by weight) 100 95-100 45-100 0.50

4.1.1.4 Stacking: Aggregate shall be stacked on a hard, dry and level patch of ground. When stack piling, the aggregate shall not form pyramids resulting in segregation of different sized materials. It shall be stacked separately according to nominal size of coarse aggregates. Stacking shall be done in regular stacks, of height not exceeding 100 cm. 4.1.1.5 Testing: Coarse aggregate shall be tested for the followings (as per IS 2386) (a) Determination of particle size and shape (Appendix ‘A’ of Chapter 4) (b) Estimation of organic impurities (as per IS 2386 - Part II) (c) Surface moisture (Appendix ‘B’ of Chapter 4) (d) Determination of 10% fine value (Appendix ‘C’ of Chapter 4) 4.1.1.6 Measurements: The aggregates shall be measured in stacks and paid for after making a deduction of 7.5% of the gross measurements of stacks in respect of aggregates of nominal size 40 mm and above. No deduction from the gross measurements of the stacks is to be made in respect of aggregate of nominal size below 40 mm. 4.1.2 Chemical Admixtures When required, admixtures of approved quality shall be mixed with concrete, as specified. The admixtures shall conform to IS 9103 and as specified in Chapter 5 - R.C.C. 91

SUB HEAD 4.0 : CONCRETE WORK

4.1.2.1 Admixtures may be any one of the following classes for use in concrete:(a) Water Reducing Admixtures (b) Retarding Admixtures (c) Accelerating Admixtures. (d) Water Reducing and Retarding Admixtures. (e) Water Reducing and Accelerating Admixtures. (f) Permeability Reducing (water proofing) Admixtures. 4.1.2.2 Liquid Admixtures: Admixtures introduced into the concrete as liquids generally fall into the following categories. (a) Air Entraining. (b) Water Reducing. (c) Water Reducing Retarders. (d) Retarders. (e) Water Reducing Accelerators. (f) Accelerators. 4.1.2.3 Dosage of these admixtures may vary according to manufacturers specification. 4.1.2.4 Two or more admixtures may not be compatible in the same solution. It is therefore mandatory that when two admixtures manufactured by the same manufacturers is being used simultaneously, the manufacturer shall certify their compatibility. In case the two or more admixtures are produces by different manufacturers, then, before their use in concrete, test shall be performed by the manufacturer to establish their compatibility, all such test reports shall be furnished to the Engineer-in-Charge for his approval before their use in concrete. 4.1.2.5 Some admixture may be in the form of powder, particle or high concentration liquids which may require mixing with water prior to dosing. Under these conditions water in solution shall be considered as part of total water content in the batch in order to maintain the water-cement ratio. 4.1.2.6 Admixture manufacturer’s recommendation shall be carefully followed so as to ensure complete solution of the product or to prepare a standard solution of uniform strength for easier use. 4.1.2.7 Certain admixtures may contain significant amounts of finely divided insoluble materials or active ingredients which may or may not be readily soluble. It is essential for such admixtures that precautions be taken to ensure that these constituents be kept in a state of uniform suspension before actual batching. When relatively small amounts of powered admixtures are to be used directly, these shall be pre-blended with cement. 4.1.2.8 Admixtures are sold under various trade names and may be in the form of liquids or powders. The proprietary name and the net quantity of content shall be clearly indicated in each package or container of admixtures. The admixtures shall be uniform within each batch and uniform between all batches. 4.1.2.9 No admixtures shall be accepted for use in concrete unless these are tested in accordance with IS 9103 and the test results are approved by the Engineer-in-Charge. 4.2. CEMENT CONCRETE 4.2.1 Grades of Cement Concrete The concrete shall be in grade designated as under:

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TABLE 4.5 Grades of Concrete Group

Grade Designation

(1) Ordinary Concrete

(2) M10 M15 M20 M25 M30 M35 M40 M45 M50 M55 M60 M65 M70 M75 M80

Standard Concrete

High Strength Concrete

Specified characteristic compressive strength of 150 mm Cube at 28 Days in N/mm2 (3) 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80

Notes : 1. In the designation of concrete mix M refers to the mix and the number to the specified compressive strength of 150 mm size cube at 28 days, expressed in N/mm2. 2. For concrete of compressive strength greater than M55, design parameters given in the standard may not be applicable and the values may be obtained from specialized literatures and experimental results. 4.2.1.1 The characteristic strength is defined as the strength of material below which not more than 5 percent of the test results are expected to fall. TABLE 4.6 Minimum Cement Content, Maximum Water-Cement Ratio and Minimum Grade of Concrete for Different Exposures with Normal Weight Aggregates of 20 mm Nominal; Maximum Size (Clause 4.2.1.1) Sl. No.

(1) (i) (ii) (iii) (iv) (v)

Exposure

(2) Mild Moderate Severe Very Severe Extreme

Plain Concrete

Reinforced Concrete

Minimum Cement Content kg/m3

Maximum Free Water Cement Ratio

Minimum Grade of Concrete

Minimum Cement Content kg/m3

(3) 220 240 250 260 280

(4) 0.60 0.60 0.50 0.45 0.40

(5) M15 M20 M20 M25

(6) 300 300 320 340 360

93

Maximum Free WaterCement Ratio (7) 0.55 0.50 0.45 0.45 0.40

Minimum Grade of Concrete

(8) M20 M25 M30 M35 M40

SUB HEAD 4.0 : CONCRETE WORK

Notes: 1. Cement content prescribed in this Table is irrespective of the grades of cement. The additions such as fly or ground granulated blast furnace slag may be taken into account in the concrete composition with respect to the cement content and water-cement ratio, if the suitability is established and as long as the maximum amounts taken into account do not exceed the limit of pozzolona and slag specified in IS 1489 (Part 1) and IS 455 respectively. 2. Minimum grade for plain concrete under mild exposure condition is not specified. 3. The above minimum cement content and maximum water cement ratio apply only to 20 mm nominal maximum size aggregate. For other sizes of aggregate, these should be changed as per Table 6 of IS 456. The minimum grade of concrete for plain and reinforced concrete shall be as per Table 4.6. 4.2.1.2 Concrete of grades lower than those given in Table 4.6 may be used for lean concrete, foundation for masonry walls or temporary reinforced concrete construction. 4.2.2 Workability of Concrete 4.2.2.1 The concrete mix proportion chosen should be such that the concrete is of adequate workability for the placing conditions of the concrete and can properly be compacted with the means available. Suggested ranges of workability of concrete measured in accordance with IS 1199 are given below: Placing Conditions

Degree of Workability

(1) Blinding concrete: shallow Very low sections: Pavements using pavers Mass concrete: Lightly Low reinforced sections in slabs, beams, wall, columns, : floors

(2)

Note:-

(3) See 4.2.2.2

25-75

Hand placed pavements: canal lining; Strip footing Heavily reinforced sections in Medium slabs, beams, walls, columns: Slip form work: Pumped Medium concrete Trench fill High Tremie concrete

Slump (mm)

50-100 75-100 100-150

Very High

See 4.2.2.3

For most of the placing conditions, internal vibrators (needle vibrators) are suitable. The diameter of the needle shall be determined based on the density and spacing of reinforcement bars and thickness of sections. For tremie concrete, vibrators are not required to be used (see also 4.2.7)

4.2.2.2 In the ‘very low’ category of workability where strict control is necessary, for example, pavement quality concrete, measurement of workability be determination of compacting factor will be more appropriate than slump ( see IS 1199) and a value of compacting factor of 0.75 to 0.80 is suggested. 4.2.2.3 In the ‘very high’ category of workability, measurement of workability by determination of flow will be appropriate (see IS 9103).

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4.2.3 Concrete Mix Proportioning 4.2.3.1 The determination of the proportion of cement, aggregate and water to attain the required strength shall be made as follows: (a) By designing the concrete mix: such concrete shall be called ‘Design mix concrete’, for details reference may be made to RCC Chapter. (b) By adopting nominal concrete mix: such concrete shall be called ‘Nominal mix concrete’. Design mix concrete is preferred to nominal mix. If design mix concrete cannot be used for any reason on the work for grades of M20 or lower, nominal mixes may be used with the permission of Engineer-in-Charge, which, however, is likely to involve a higher cement content. 4.2.3.2 Nominal Mix Concrete: Nominal Mix Concrete may be used for concrete of M20 or lower. The proportions of materials for nominal mix concrete shall be in accordance with Table 4.7. The cement content of the mix specified in Table 4.7 for any nominal mix shall be proportionately increased if the quantity of water in the mix has to be increased to overcome the difficulty or placement and compaction, so that the water cement ratio as specified is not exceeded.

TABLE 4.7 Proportions for Nominal Mix Concrete (Clause 4.2.3.2) Grade of Concrete

(1) M5 M7.5 M10 M15 M20 Note : -

Note : -

Total Quantity of Dry Aggregates by Mass per 50 kg of cement, to be taken as the Sum of the Individual Masses of Fine and Coarse Aggregates, Kg. Max (2) 800 625 480 330 250

Proportion of Fine Aggregate to Coarse Aggregate (by Mass)

(3) Generally 1:2 but subject to an upper limit of 1: 1 ½ and a lower limit of 1:2 ½

Quantity of Water per 50 kg of Cement, max Ltr.

(4) 60 45 34 32 30

The proportion of the fine to coarse aggregate should be adjusted from upper limit progressively as the grading of fine aggregate becomes finer and the maximum size of coarse aggregate becomes larger. Graded coarse aggregate shall be used. Quantity of water required from durability point of view may be less than the value given above.

Example For an average grading of fine aggregate (that is, Zone II of Table 4 of IS 383), the proportions shall be 1:1 ½ , 1:2 and 1:2 ½ for maximum size of aggregates 10 mm, 20 mm and 40 mm respectively. 4.2.4 Batching To avoid confusion and error in batching, consideration should be given to using the smallest practical number of different concrete mixed on any site or in any one plant. In batching concrete, the quantity of both cement and aggregate shall be determined by mass; admixture, if solid, by mass: liquid 95

SUB HEAD 4.0 : CONCRETE WORK

admixture may however be measured in volume or mass: water shall be weighed or measured by volume in a calibrated tank (see also IS 4925). Ready-mixed concrete supplied by ready-mixed concrete plant shall be preferred. For large and medium project sites the concrete shall be sourced from ready-mixed concrete plants or from on site or off site batching and mixing plants (see IS 4926). 4.2.4.1 Except where it can be shown to the satisfaction of the Engineer-in-Charge that supply of properly graded aggregate of uniform quality can be maintained over a period of work, the grading aggregate should be controlled by obtaining the coarse aggregate in different sizes and blending them in the right proportions when required, the different sizes being stocked in separate stock-piles. The material should be stock-piled for several hours preferably a day before use. The grading of coarse and fine aggregate should be checked as frequently as possible, the frequency for a given job being determined by the Engineer-in-Charge to ensure that the specified grading is maintained. 4.2.4.2 The accuracy of the measuring equipment shall be within + 2 percent of the quantity of cement being measured and within + 3 percent of the quantity of aggregate, admixtures and water being measured. 4.2.4.3 Proportion/Type and grading of aggregates shall be made by trial in such a way so as to obtain densest possible concrete. All ingredients of the concrete should be used by mass only. 4.2.4.4 Volume batching may be allowed only where weigh-batching is not practicable and provided accurate used in concrete have earlier been established. Allowance for bilking shall be made in accordance with IS 2386 (Part 3). The mass volume relationship should be checked as frequently as necessary, the frequency for the given job being determined by Engineer-in-Charge to ensure that the specified grading is maintained. 4.2.4.5 It is important to maintain the water cement ratio constant at its correct value. To this end, determination of moisture contents in both fine and coarse aggregates shall be made as frequently as possible, the frequency for a given job being determined by the Engineer-in-Charge according to weather conditions. The amount of the added water shall be adjusted to compensate for any observed variations in the moisture contents. For the determination of moisture content in the aggregates, IS 2386 (Part 3) may be referred to. To allow for the variation in mass for aggregate due to variations in their moisture content, suitable adjustments in the masses of aggregates shall be made. In the absence of exact data, only in the case of nominal mixes, the amount of surface water may be estimated from the values given in Table 4.8. TABLE 4.8 Surface Water Carried by Aggregate (Clause 4.2.4.5) Sl No.

Aggregate

(1) (i) (ii) (iii) (iv)

(2) Very wet sand Moderately wet sand Moist sand 1) Moist gravel or crushed rock 1) Coarser the aggregate, less the water it will carry.

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Approximate Quantity of Surface Water Percent by l/m3 mass (3) (4) 7.5 120 5.0 80 2.5 40 1.25-2.5 20-40

4.2.4.6 No substitutions in materials used on the work or alteration in the established proportions, except as permitted in 4.2.4.4 and 4.2.4.5 shall be made without additional tests to show that the quality and strength of concrete are satisfactory. 4.2.5 Mixing Concrete shall be mixed in mechanical batch type concrete mixers conforming to IS 1791 having two blades and fitted with power loader (lifting hopper type). Half bag mixers and mixers without lifting hoppers shall not be used for mixing concrete. In exceptional circumstances, such as mechanical break down of mixer, work in remote areas or power breakdown and when the quantity of concrete work is very small, hand mixing may be done with the specific prior permission of the Engineer-in-Charge in writing subject to adding 10% extra cement. When hand mixing is permitted, it shall be carried out on a water tight platform and care shall be taken to ensure that mixing is continued until the concrete is uniform in colour and consistency. Before mixing the brick aggregate shall be well soaked with water for a minimum period of two hours and stone aggregate or gravel shall be washed with water to remove, dirt, dust and other foreign materials. For guidance, the mixing time may be 11/2 to 2 minutes, for hydrophobic cement it may be taken as 21/2 to 3 minutes. 4.2.5.1 Power Loader: Mixer will be fitted with a power loader complying with the following requirements. (a) The hopper shall be of adequate capacity to receive and discharge the maximum nominal batch of unmixed materials without spillage under normal operating conditions on a level site. Note: In such a case the volume of the maximum nominal batch of mixed material is 50% greater than the nominal mixed batch capacity. (b) The minimum inside width of the feeding edge of the hopper shall be as specified below in Table 4.9. TABLE 4.9 Nominal size of mixer (T, NT or R). litre 140 200 280 375 500 1000 T = Tilting;

Minimum inside width of hopper feeding edge 1.0 1.1 1.2 1.4 1.5 2.0

NT = Non-tilting;

R = Reverse

(c) The design of the loader shall be such that it allows the loading hopper to be elevated to such a height that the centre line of the chute plate of the hopper when in discharge position, is at an angle of not less than 50º to the horizontal. A mechanical device to aid discharge of the contents as quickly as possible from the hopper to the drum may also be provided. Even when a mechanical device is provided, it is recommended that the angle of centre line of the chute plate of the hopper when in discharge position, should be as larger as practicable, preferably not less than 40º to horizontal. (d) When the means of raising and lowering the loading hopper includes flexible wire ropes winding on to a drum or drums, the method of fastening the wire to rope to the drums shall be such as to avoid, as far as possible any tendency to cut the strands of the ropes and the fastening should preferably be positioned clear of the barrel of the drum for example, outside the drums flange. When the loading hopper is lowered to its normal loading position, these should be at least one and a half drums of rope on the drum. 97

SUB HEAD 4.0 : CONCRETE WORK

(e) Clutch brake and hydraulic control lever shall be designed so as to prevent displacement by liberation or by accidental contact with any person. (f) The clutch and brake control arrangements shall also be so designed that the operator can control the falling speed of the loader. (g) Safety device shall be provided to secure the hopper in raised position when not in use. 4.2.5.2 Mixing Efficiency: The mixer shall be tested under normal working conditions in accordance with the method specified in IS 4643 with a view to check its ability to mix the ingredients to obtain concrete having uniformity within the prescribed limits. The uniformity of mixed concrete shall be evaluated by finding the percentage variation in quantity (mass in water) of cement, fine aggregate and coarse aggregate in a freshly mixed batch of concrete. The percentage variation between the quantities of cement, fine aggregate and coarse aggregates (as found by weighing in water) in the two halves of a batch and average of the two halve of the batch shall not be more than the following limits: Cement Fine aggregate Coarse aggregate

8% 6% 5%

4.2.5.3 Machine Mixing: The mixer drum shall be flushed clean with water. Measured quantity of coarse aggregate shall be placed first in the hopper. This shall be followed with measured quantity of fine aggregate and then cement. In case fine aggregate is damp, half the required quantity of coarse aggregate shall be placed in the hopper, followed by fine aggregate and cement. Finally the balance quantity of coarse aggregate shall be fed in the hopper, & then the dry materials are slipped into the drum by raising the hopper. The dry material shall be mixed for atleast four turns of the drum. While the drum is rotating, water shall be added gradually to achieve the water cement ratio as specified or as required by the Engineer-in-Charge. After adding water, the mixing shall be continued until concrete of uniform colour, uniformly distributed material and consistency is obtained. Mixing shall be done for atleast two minutes after adding water. If there is segregation after unloading from the mixer, the concrete should be remixed. The drum shall be emptied before recharging. When the mixer is closed down for the day or at any time exceeding 20 minutes, the drum shall be flushed cleaned with water. 4.2.5.4 Hand Mixing: When hand mixing has been specifically permitted in exceptional circumstances by the Engineer-in-Charge in writing, subject to adding 10% extra cement, it shall be carried out on a smooth, clean and water tight platform of suitable size. Measured quantity of sand shall be spread evenly on the platform and the cement shall be dumped on the sand and distributed evenly. Sand and cement shall be mixed intimately with spade until mixture is of even colour throughout. Measured quantity of coarse aggregate shall be spread on top of cement sand mixture and mixing done by showlling and turning till the coarse aggregate gets evenly distributed the cement sand mixture. Three quarters of the total quantity of water required shall be added in a hollow made in the middle of the mixed pile and the material is turned towards the middle of pile with spade. The whole mixture is turned slowly over and again and the remaining quantity of water is added gradually. The mixing shall be continued until concrete of uniform colour and consistency is obtained. The mixing platform shall be washed and cleaned at the end of the day. 4.2.5.5 Transportation and Handling : Concrete shall be transported from the mixer to the place of laying as rapidly as possible by methods which will prevent the segregation or loss of any of the ingredients and maintaining the required workability.

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During hot or cold weather, concrete shall be transported in deep containers, other suitable methods to reduce the loss of water by evaporation in hot weather and heat loss in cold weather may also be adopted. 4.2.6 Placing The concrete shall be deposited as nearly as practicable in its final position to avoid rehandling. It shall be laid gently (not thrown) and shall be thoroughly vibrated and compacted before setting commences and should not be subsequently disturbed. Method of placing shall be such as to preclude segregation. Care shall be taken to avoid displacement of reinforcement or movement of form work and damage due to rains. As a general guidance, the maximum free fall of concrete may be taken as 1.5 metre. 4.2.7 Compaction Concrete shall be thoroughly compacted and fully worked around embedded fixtures and into corners of the form work. Compaction shall be done by mechanical vibrator of appropriate type till a dense concrete is obtained. The mechanical vibrators shall conform to IS 2505, IS 2506, IS 2514 and IS 4656. To prevent segregation, over vibration shall be avoided. Compaction shall be completed before the initial setting starts. For the items where mechanical vibrators are not to be used, the contractor shall take permission of the Engineer-in-Charge in writing before the start of the work. After compaction the top surface shall be finished even and smooth with wooden trowel before the concrete begins to set. 4.2.8 Construction Joints Concreting shall be carried out continuously upto construction joints. The position and arrangement of construction joints shall be as shown in the structural drawings or as directed by the Engineer-inCharge. Number of such joints shall be kept minimum. Joints shall be kept as straight as possible. Construction joints should comply with IS 11817. 4.2.8.1 When the work has to be resumed on a surface which has hardened, such surface shall be roughened. It shall then be swept clean and thoroughly wetted. For vertical joints, neat cement slurry, of workable consistency by using 2 kgs of cement per sqm shall be applied on the surface before it is dry. For horizontal joints, the surface shall be covered with a layer of mortar about 10-15 mm thick composed of cement and sand in the same ratio as the cement and sand in concrete mix. This layer of cement slurry of mortar shall be freshly mixed and applied immediately before placing of the concrete. 4.2.8.2 Where the concrete has not fully hardened, all laitance shall be removed by scrubbing the wet surface with wire or bristle brushes, care being taken to avoid dislodgement of particles of coarse aggregate. The surface shall be thoroughly wetted and all free water removed. The surface shall then be coated with neat cement slurry @ 2 kgs of cement per sqm. On this surface, a layer of concrete not exceeding 150 mm in thickness shall first be placed and shall be well rammed against old work particular attention being paid to corners and close spots; work, thereafter, shall proceed in the normal way. 4.2.9 Concreting under Special Conditions 4.2.9.1 Work in Extreme Weather Conditions: During hot and cold weather, the concreting shall be done as per the procedure set out in IS 7861 (Part–I)-1975 and IS 7861 (Part II)-1981 respectively. Concreting shall not be done when the temperature falls below 4.5ºC. In cold weather, the concrete placed shall be protected against frost. During hot weather, it shall be ensured that the temperature of wet concrete does not exceed 38ºC.

99

SUB HEAD 4.0 : CONCRETE WORK

4.2.9.2 Under Water Concreting: Concrete shall not be deposited under water if it is practicable to dewater the area and place concrete in the regular manner. When it is necessary to deposit concrete under water, the methods, equipment, materials and proportions of the mix to be used shall be submitted to and approved by the Engineer-in-Charge before the work is started. Under-water concrete should have a slump recommended in 4.2.2. The water-cement ratio shall not exceed 0.6 and may need to be smaller, depending on the grade of concrete or the type of chemical attack. For aggregates of 40 mm maximum particle size, the cement content shall be atleast 350 kg/m3 of concrete. 4.2.9.3 Concrete in Sea Water: Concrete in sea-water or exposed directly along the sea-coast shall be at least M20 Grade in the case of plain concrete and M30 in case of reinforced concrete. The use of slag or pozzolana cement is advantageous under such conditions. (i) Special attention shall be given to the design of the mix to obtain the densest possible concrete: slag, broken brick, soft lime stone, soft sandstone, or other porous or weak aggregates shall not be used. (ii) As far as possible, preference shall be given to precast members unreinforced, well-cured and hardened, without sharp corners, and having trowel-smooth finished surfaces free from crazing, cracks or other defect; plastering should be avoided. (iii) No construction joints shall be allowed within 600 mm below low water-level or within 60 mm of the upper and lower planes of wave action. Where unusually severe conditions or abrasion are anticipated, such parts of the work shall be protected by bituminous or silico-fluoride coatings or stone facing bedded with bitumen. (iv) In reinforced concrete structures, care shall be taken to protect the reinforcement from exposure to saline atmosphere during storage, fabrication and use. It may be achieved by treating the surface of reinforcement with cement wash or by suitable methods. 4.2.10 Curing Curing is the process of preventing loss of moisture from the concrete. The following methods shall be employed for effecting curing. 4.2.10.1 Moist Curing : Exposed surfaces of concrete shall be kept continuously in a damp or wet condition by ponding or by covering with a layer of sacking, canvas, Hessian or similar materials and kept constantly wet for at least 7 days from the date of placing concrete in case of ordinary Portland cement and at least 10 days where mineral admixtures or blended cements are used. The period of curing shall not be less than 10 days for concrete exposed to dry and hot weather conditions. In the case of concrete where mineral admixtures or blended cements are used, it is recommended that above minimum periods may be extended to 14 days. 4.2.10.2 Membrane Curing : Approved curing compounds may be used in lieu of moist curing with the permission of the Engineer-in-Charge. Such compound shall be applied to all exposed surfaces of the concrete as soon as possible after the concrete has set. Impermeable membrane such as polythene sheet covering the concrete surface may also be used to provide effective barrier against the evaporation. 4.2.10.3 Freshly laid concrete shall be protected from rain by suitable covering.

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4.2.10.4 Over the foundation concrete, the masonry work may be started after 48 hours of its compaction but the curing of exposed surfaces of cement concrete shall be continued along with the masonry work for at east 7 days. And where cement concrete is used as base concrete for flooring, the flooring may be commenced before the curing period of base concrete is over but the curing of base concrete shall be continued along with top layer of flooring for a minimum period of 7 days. 4.2.11 Testing of Concrete Testing of concrete shall be done as described in chapter of R.C.C. 4.2.12 Form Work Form work shall be as specified in R.C.C. chapter and shall be paid for separately unless otherwise specified. 4.2.13 Finishes Plastering and special finishes other than those, obtained through form work shall be specified and paid for separately unless otherwise specified. 4.2.14 Durability of Concrete A durable concrete is one that performs satisfactorily in the working environment during its anticipated exposure conditions during service. The materials and mix proportions shall be such as to maintain its intergrity and, if applicable, to protect reinforcement from corrosion. The factors influencing durability include: (a) The environment; (b) The cover to embedded steel; (c) The type and quality of constituent materials; (d) The cement content and water/ cement ratio of the concrete; (e) Workmanship, to obtain full compaction and efficient curing; and (f) The shape and size of the member. 4.2.14.1 Requirements for Durability 4.2.14.1.1 General Evironment : The general environment to which the concrete will be exposed during its working life is classified into five levels of severity, that is, mild, moderate, severe, very severe and extreme as described in Table 4.9. TABLE 4.9 Environmental Exposure Conditions Sl. No (1) (i)

Environment (2) Mild

Exposure Conditions (3) Concrete surfaces protected against weather or aggressive conditions, except those situated in coastal area.

(ii)

Moderate

(iii)

Severe

Concrete surfaces sheltered from severe rain or freezing whilst wet Concrete exposed to condensation and rain Concrete continuously under water Concrete in contact or buried under non-aggressive soil/ ground water Concrete surfaces sheltered from saturated salt air in coastal area Concrete surfaces exposed to severe rain, alternate weting and drying or occasional freezing whilst wet or severe condensation. Concrete completely immersed in sea water. Concrete exposed to coastal environment.

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SUB HEAD 4.0 : CONCRETE WORK

(1) (iv)

(2) Very severe

(v)

Extreme

Note:

(3) Concrete surface exposed to sea water spray, corrosive fumes or severe freezing conditions whilts wet. Concrete in contact with or buried under aggressive sub-soil/ ground water. Surface of members in tidal zone. Members in direct contact with liquid/ solid aggressive chemicals.

For the purpose of determining exposure conditions, all places within a distance of 10 kms. of coastal line, sea front would be treated as coastal area.

4.2.14.1.2 Freezing and Thawing : Where freezing and thawing actions under wet conditions exist, enhanced durability can be obtained by the use of suitable air entraining admixtures. When concrete lower than grade M50 is used under these conditions, the mean total air content by volume of the fresh concrete at the time of delivery into the construction should be: Nominal Maximum Size Aggregate (mm) 20 40

Entrained Air Percentage 5+1 4+1

4.2.14.1.3 Exposure to Sulphate Attack : For the very high sulphate concentration in Class 5 conditions given in Table 4.11, some form of lining such as polyethylene or polychloroprene sheet: or surface coating based on asphalt, chlorinated rubber, epoxy; or polyurethane materials should also be used to prevent access by the sulphate solution. 4.2.14.1.4 Chlorides in Concrete : The total amount of chlorides content (as CI) in the concrete at the time of placing shall be as under : SI. No.

Type of Use of Concrete

(1) (i)

(2) Concrete containing metal and steam cured at elevated temperature and pre-stressed concrete Reinforced concrete or plain concrete containing embedded metal Concrete not containing embedded metal or any material requiring protection from chloride

(ii) (iii)

Maximum Total Acid Soluble Chloride Content expressed as kg/ m3 of Concrete (3) 0.4 0.6 3.0

4.2.14.1.5 Sulphates in Concrete : The total water-soluble sulphate content of the concrete mix, expressed as SO3 should not exceed 4 per cent by mass of the cement in the mix. The sulphate content should be calculated as the total from the various constituents of the mix. The 4 per cent limit does not apply to concrete made with supersulphate cement complying with IS 6909.

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TABLE 4.11 Requirements for Concrete Exposed to Sulphate Attack (Clause 4.2.14.1.3) Sl No.

Class

In Soil Total SO3 (%) (1) (i)

(2) 1

(ii)

2

(iii)

3

Type of Cement

Concentration of sulphates, Expresed as SO3 Concrete.

(3) Traces (<0.2)

0.2 to 0.5

0.5 to 1.0

SO3 in 2:1 (Water: Soil Extract) ( g/l) (4) Less than 1.0

1.0 to 1.9

1.9 to 3.1

In Ground Water (g/l)

(5) Less than 0.3

0.3 to 1.2

1.2 to 2.5

(iv)

4

1.0 to 2.0

3.1 to 5.0

2.5 to 5.0

(v)

5

More than 2.0

More than 5.0

More than 5.0

(6) Ordinary Portland cement or Portland slag cement or Portland pozzolana cement Ordianry Portland cement or Portland slag cement or Portland pozzolana cement

Dense, Fully compacted made with 20 mm nominal maximum size Aggregates complying with IS 383 Minimum Maximum Cement Free Content Water3 kg/m Cement Ratio (7) (8) 280 0.55

330

0.50

Supersulphated cement or sulphate resisting Portland cement Supersulphated cement or sulphate resisting Portland cement

310

0.50

330

0.50

Portland Pozzolana cement or Portland slag cement Supersulphated or sulphate resisting Portland cement Sulphate resisting Portland cement or supersulphated cement with protective coatings

350

0.45

370

0.45

400

0.40

Notes 1. Cement content given in this Table is irrespective of grades of cement. 2. Use of supersulphated cement is generally restricted where the prevailing temperature is above 40°C. 3. Supersulphated cement gives an acceptable life provided that the concrete is dense and prepared with a water-cement ratio of 0.4 or less, in mineral acids, down to pH 3.5. 4. The cement contents given in col. 7 of this Table are the minimum recommended. For SO3 contents near the upper limit of any class, cement contents above these minimum are advised. 5. For severe conditions, such as thin sections under hydrostatic pressure on one side only and sections partly immersed, considerations should be given to a further reduction of water-cement ratio. 6. Portland slag cement conforming to IS 455 with slag content more than 50 per cent exhibits better sulphate resisting properties.

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7. Where chloride is encountered along with sulphates in soil or ground water, ordinary Portland cement with C3A content from 5 to 8 per cent shall be desirable to be used in concrete, instead of suplhate resisting cement. Alternatively, Portland slag cement conforming to IS 455 having more than 50 per cent slag or a blend of ordinary Portland cement and slag may be used provided sufficient information is available on performance of such blended cements in these conditions. 4.2.15 Measurements 4.2.15.1 Dimensions of length, breadth and thickness shall be measured correct to nearest cm. except for the thickness of slab and partition which shall be measured to nearest 5 mm. Areas shall be worked out to nearest 0.01 sq.m and the cubic contents of consolidated concrete shall be worked out to nearest 0.01 cum. Any work done in excess over the specified dimension or sections shown in the drawing shall be ignored. 4.2.15.2 Concrete work executed in the following conditions shall be measured separately: (a) Work in or under water (b) Work in liquid mud (c) Work in or under foul positions 4.2.15.3 Cast-in-situ concrete and or precast concrete work shall be measured in stages described in the item of work, such as: (a) At or near the ground level (b) Upto specified floor level (c) Between two specified floor levels (d) Upto specified height above or depth below plinth level/ defined datum level. (e) Between tow specified heights or depths with reference to plinth/defined datum level. 4.2.15.4 No deduction shall be made for the following: (a) Ends of dissimilar materials for example beams, posts, girders, rafters, purlins, trusses, corbels and steps upto 500 sq cm in cross sections. (b) Opening upto 0.1 sq metre (1000 sq.cm) (c) Volume occupied by pipes, conduits, sheathing etc. not exceeding 100 sq cm each in cross sectional areas. (d) Small voids such as shaded portions in Figure A to J below when these do not exceed 40 sq cm each in cross section. Note: In calculating area of opening, the thickness of any separate lintel or sill shall be included in the height. Nothing extra shall be payable for forming such openings or voids. Area of Fig. A to G shall be = L x B Area of Fig. H & J shall be

CPWD SPECIFICATIONS 2009

= L x {Average of B and B’}

104

B

B

B

L

L

L

A

B

C

B

B

B

L

L

L

D

E

F

B

B

B'

B

B'

L

L

L

G

H

J

4.2.15.5 Cast-in-situ and precast concrete work shall be measured sperately. 4.2.15.6 Cast-in-situ concrete shall be classified and measured as follows: (a) Foundation, footings, bases for columns (b) Walls (any thickness) including attached pilasters, buttresses, plinth and string courses, fillets etc. (c) Shelves (d) Slabs (e) Chajjas including portions bearing on the wall (f) Lintels, beams and bressummers (g) Columns, piers abutments, pillars, post and struts (h) Stair case including stringer beams but excluding landings. (i) Balustrades, newels and sailing (j) Spiral staircase (including landings) (k) Arches (I) Domes, vaults (m) Shell roof, arch ribs and folded piates (n) Chimneys and shaft. (o) Breast walls, retaining, walls, return walls (p) Concrete filling to precast components (q) Kerbs, steps and the like (r) String or lacing courses, parapets, copings, bed block, anchor blocks, plain window sills and the like (s) Cornices and moulded windows sills. (t) Louvers, fins, facia. 4.2.15.7 Precast cement concrete solid article shall be measured separately and shall include use of moulds, finishing the top surfaces even and smooth with wooden trowel, before setting in position in

105

SUB HEAD 4.0 : CONCRETE WORK

cement mortar 1:2 (1 cement : 2 coarse sand). Plain and moulded work shall be measured separately and the work shall be classified and measured as under: Classifications (a) Wall panels (b) String or lacing courses, coping, bed plates, plain windows sills, shelves, louvers, steps etc. (c) Kerbs, edgings etc. (d) Solid block work (e)

Hollow block work

(f)

Light weight partitions

Method of measurement In square meters stating the thickness. In cubic meters.

In cubic metres. In square metres stating the thickness or in cubic meters. In square metres stating the thickness or in cubic metres. In square metres stating the partition’s thickness.

4.2.16 Rate The rate is inclusive of the cost of labour and materials involved in all the operations described above. 4.3 CEMENT- FLY ASH CONCRETE 4.3.0 Fly ash concrete shall be prepared by mixing graded coarse aggregate of nominal size as specified with fine aggregate, ordinary Portland cement and fly ash in specified proportions with required quantity of water. The recommended composition of cement fly ash concrete are as under: TABLE 4.12 Fly Ash Concrete Mixes Composition (Dry Volume)

Proportion (Dry Volume)

Lean Concrete (1:5:10) Cement (Ordinary Portland) Fly ash Sand Stone aggregate Lean Concrete (1:4:8) Cement (Ordinary Portland) Fly ash Sand Stone aggregate

1.0 2.5 4.0 11.0 1.0 2.0 3.5 9.0

Compressive Strength at seven days

28 kg/cm2

37 kg/cm2

Note: No fly ash is to be added to Portland Puzzolona cement in any case which itself contains fly ash. 4.3.1 Proportioning Proportioning shall be done by volume. Boxes of suitable size shall be used for measuring fly ash, sand and aggregate. The internal dimensions of the boxes shall be generally 35x25x40 cm. deep or as otherwise approved by the Engineer-in-charge. The unit of measurement of cement shall be a bag of 50 kg. and this shall be taken as 0.035 cum. While measuring the aggregate, shaking, ramming or heaping shall not be done. The proportioning of sand shall be on the basis of its dry volume and in case of damp sand, allowances for bulkage shall be made as given in the chapter for mortar.

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4.3.2 Mixing shall be as specified in 4.2.5 except that the fly ash shall be placed in the hopper before cement in case of machine mixing. 4.3.3 Placing and compaction shall be as specified in 4.2.6 and 4.2.7. 4.3.4 Curing shall be as specified in 4.2.10. 4.3.5 Form work shall be as specified in 4.2.12. 4.3.6 Measurements shall be as specified in 4.2.15. 4.3.7 Rate Rate shall include the cost of materials and labour involved in all the operations described above. 4.4 DAMP PROOF COURSE 4.4.1 Cement Concrete Layer This shall consist of cement concrete of specified proportions and thickness. The surface of brick or stone masonry work shall be levelled and prepared before laying the cement concrete. Edge of damp proof course shall be straight, even and vertical. Side shuttering shall consist of steel forms and shall be strong and properly fixed so that it does not get disturbed during compaction and the mortar does not leak through. The concrete mix shall be of workable consistency and shall be tamped thoroughly to make a dense mass. When the sides are removed, the surface should come out smooth without honeycoming. Continuity shall be maintained while laying the cement concrete layer and laying shall be terminated only at the predetermined location where damp proof course is to be discontinued. There shall be no construction joints in the Damp Proof Course. 4.4.2 Curing Damp proof course shall be cured for at least seven days, after which it shall be allowed to dry. 4.4.3 Application of Hot Bitumen Where so directed, hot bitumen in specified quantity shall be applied over the dried up surface of cement concrete, properly cleaned with brushes and finally with a piece of cloth soaked in kerosene oil. Bitumen of penetration A 90 or equivalent where used shall be heated to a temperature of 160º ± 5ºC. The hot bitumen shall be applied uniformly all over, so that no blank spaces are left anywhere. It will be paid for separately. 4.4.4 Water Proofing Materials Where so specified, water proofing material of approved quality shall be added to the concrete mixture in accordance with the manufacturer’s specification stating the quantity of water proofing material in litres or kg per 50 kg or cement and will be paid for separately. 4.4.5 Measurements The length and breadth shall be measured correct to a cm and its area shall be calculated in square metres correct to two places of decimal. The depth shall not be less than the specified thickness at any section. 4.4.6 Rate The rate is inclusive of the cost of materials and labour involved in all the operations described above except for the applications of a coat of hot bitumen and addition of water proofing materials which shall be paid for separately, unless otherwise specified.

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APPENDIX A

DETERMINATION OF PARTICLE SIZE (Clause 4.1.2.3 & 4.1.2.5) The apparatus, sample size and test procedure shall be same as specified in sub-head ‘MORTARS’. In order that the sieves shall not be overloaded, care must be taken to ensure that the maximum sieve loads shown in Table A-4.1 (below) are not exceeded at the completion of sieving. TABLE A-4.1

I.S. Sieve Designation 45 mm 40 mm 31.5 mm or 22.1 mm 20 mm 16 mm or 12.5 mm 10 mm 5.6 mm 4.75 mm 3.35 mm

Maximum weight for 45 cm dia sieve 30 cm dia sieve kg kg 10 4.5 8 3.5 6 2.5 4 2.0 3 1.5 2 1.0 1.5 0.75 1.0 0.50 0.30

The sample weight taken will thus normally require several operations on each sieve. Each sieve should be taken separately over a clean tray or receiver until no more than a trace passes, but in any case for not less than two minutes. Materials should not be forced through the apertures but hand placing is permitted. A light brush should be used with fine sieves. The cumulative weight passing each sieve should be calculated as percentage of the total sample weight to the nearest whole number.

APPENDIX B

TEST FOR SURFACE MOISTURE (Clause 4.1.1.5) Take a sample of wet aggregate and weigh it (A). Then place it in a frying pan and gently apply heat, meanwhile stirring with a glass rod until the surface moisture disappears. This is apparent when the aggregate loses its shining wet appearance and becomes dull, or when it just attains a free funning condition. The saturated surface dry material is then weighed (B). Continue the heating thereafter until the moisture is evaporated and weigh the dry sample (C). The surface moisture is then calculated as follows: Surface moisture = 100 x A-B C It is expressed as a percentage of dry aggregate.

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APPENDIX C

DETERMINATION OF TEN PER CENT FINE VALUE (Clause 4.1.1.5) Apparatus: The apparatus for the standard test shall consist of the following: (a) A 15 cm diameter open-ended steel cylinder, with plunger and base-plate, as shown in Fig. in the end of this appendix. The surfaces in contact with the aggregate shall be machined and case hardened or otherwise treated so as to have a diamond (VH) pyramid hardness number of not less than 650 VH. (b) A straight metal tamping rod of circular cross-section 16 mm in diameter and 45 to 60 cm long, rounded at one end. (c) A balance of capacity 3 Kg, readable and accurate to one gram. (d) I.S. Sieve of sizes 12.5, 10 and 2.36 mm. (e) A compression testing machine capable of applying a load of 50 tonnes and which can be operated to give a uniform rate of loading so that the maximum load in any test is reached in 10 minutes. This load may vary from 0.5 to 50 tonnes. (f) For measuring the sample, a cylindrical metal measure of sufficient rigidity to retain its form under rough usage and of the following internal dimensions: Diameter Height

11.5 cm 18.0 cm

(g) Means of measuring the reduction in the distance between the plates of the testing machine to the nearest one millimetre during the test (for example, dial gauge). Test Sample: Material for the test shall consist of aggregate passing a 12.5 mm I.S. Sieve and retained on a 10 mm I.S. Sieve. The aggregate shall be tested in a surface dry condition. If dries by heating the period of drying shall not exceed four hours, the temperature shall be 100ºC to 110ºC and the aggregate shall be cooled to room temperature before testing. The quantity of aggregate shall be such that the depth of material in the cylinder, after tamping as described below, shall be 10 cm. The weight of material comprising the test sample shall be determined (weight A) and the same weight of sample shall be taken for the repeat test. Note: About 6.5 kg of natural aggregate is required to provide the two test samoles. Less of light weight aggregate is required. The measuring cylinder is filled in three layers of approximately equal depth with aggregate passing a 12.5 mm I.S. Sieve and retained on 10 mm I.S. Sieve. Each layer is subjected to 25 strokes from the tamping rod (16 mm dia and 45 to 60 cm long) rounded to one end, care being taken in case of weak materials not to break the particles. The surface of the aggregate shall be carefully levelled and the plunger inserted so that it rests horizontally on this surface. Test Procedure: The apparatus, with the test sample and plunger in position, shall then be placed in the compression testing machine. The load shall be applied at a uniform rate so as to cause a total penetration of a plunger in 10 minutes of about: 15.0 mm for rounded or partially rounded aggregates 109

SUB HEAD 4.0 : CONCRETE WORK

(for example uncrushed gravel) 20 mm for nominal crushed aggregate & 24 mm for honey combed aggregate (for example expanded shales and slags). These figures may be varied according to the extent of the rounding or honey combing. After reaching the required maximum penetration, the load shall be released and the whole of the material removed from the cylinder and sieved on a 2.36 mm I.S. Sieve. The fines passing the sieve shall be weighed, and this weight expressed as a percentage of the weight of the test sample. Normally, this percentage will fall within the range 7.5 to 12.5, but if it does not, a further test shall be made at a load adjusted appropriately, to bring the percentage fines within the range of 7.5 to 12.5. A repeat test shall be made at the load that gives as percentage fines within the range 7.5 to 12.5. Calculations: The mean percentage fines from the two tests at this load shall be used in the following formula to calculate the load required to give 10 percentage fines. Load required for 10 percent fines = Where

14 × X Y+4

X = Load in tonnes and Y= mean percentage fines from two test at X tonnes load.

Reporting of Results: The load required to produce 10 percent fines shall be reported to the nearest whole number for loads of 10 tonnes or more, the nearest 0.5 tonne for loads of less than 10 tonnes. The value expressed to the nearest 0.5 tonne should be as follows: (a) For normal concrete, not less than 5 tonnes. (b) For wearing surfaces, not less than 10 tonnes. (c) For granolithic concrete, not less than 15 tonnes. 100 to 150 φ

20 φ

< 25

130 to 140

150 ± 0.5 dia of Piston

6.3

152.00 ± 0.5

< 16

200 to 230

< 16

Drawing not to Scale All dimensions in millimetres

Internal Diameter of Cylinder = 152.0± 0.5

Fig. C-4.1 : Apparatus for Determination of Ten per cent Fine Value CPWD SPECIFICATIONS 2009

110

APPENDIX D

SLUMP TEST (Clause 4.2.2) Apparatus: Mould shall consist of a metal frustum of cone having the following internal dimensions: Bottom diameter……………………………………………………..20 cm Top diameter…………………………………………………………10 cm Height…………………………………………………………………30 cm The mould shall be of a metal other than brass and aluminium of at least 1.6 mm (or 16 BG) thickness. The top and bottom shall be open and at right angles to the axis of the cone. The mould shall have a smooth internal surface. It shall be provided with suitable foot pieces and handles to facilitate lifting it from the moulded concrete test specimen in a vertical direction as required by the test. A mould provided with a suitable guide attachment may be used. Tamping rod shall be of steel or other suitable material 16 mm in diameter 60 mm long and rounded at one end. Procedure: The internal surface of the mould shall be thoroughly cleaned and free form superfluous moisture and any set concrete before commencing the test. The mould shall be placed on a smooth horizontal, rigid and non-absorbent surface viz. levelled metal plate. The operator shall hold the mould firmly in place while it is being filled with test specimen of concrete. The mould shall be filled in four layers, each approximately one quarter of height of mould. Each layer shall be tamped with twenty five strikes of the rounded end of the tamping rod. The strokes shall be distributed in a uniform manner over the cross section of the mould and for the second and subsequent layers shall penetrate into the underlying layer. The bottom layer shall be tamped through out its depth. After the top layer has been rodded, the concrete shall be struck off level with trowel or the tamping rod, so that the mould is exactly filled. Any mortar which shall leak out between the mould and the base plate shall be cleaned away. The mould shall be removed from the concrete immediately after filling by raising it slowly and carefully in a vertical direction. The moulded concrete shall then be allowed to subside and the slump shall be measured immediately by determining the difference between the height of the mould and that of the highest point of specimen. The above operations shall be carried out at a place free from vibration or shock, and within a period of two minutes after sampling. Result: The slump shall be recorded in terms of millimeters of subsidence of the specimen during the test. Any slump specimen which collapses or shears off laterally give incorrect result. If this occurs, the test shall be repeated with another sample. The slump test shall not be used for very dry mixes as the results obtained are not accurate.

111

SUB HEAD 4.0 : CONCRETE WORK

CPWD SPECIFICATIONS 2009

112

SUB HEAD : 5.0

REINFORCED CEMENT CONCRETE WORK

CONTENTS Clause No.

Brief Description List of Mandatory Tests

Page No. 119

List of Bureau of Indian Standard Codes

122

5.0

General

123

5.1 5.1.1 5.1.2

123 123 123

5.1.3 5.1.4 5.1.5

Materials Water, Cement, Fine and Coarse Aggregate Fly Ash Admixed Cement Concrete (FACC) and Fly Ash Blended Cements in Cement Concrete (PPCC) in RCC Structures Steel for Reinforcement Stacking & Storage Identification

124 126 127

5.2 5.2.1 5.2.2 5.2.3 5.2.4 5.2.5 5.2.6 5.2.7

Form Work (Centring & Shuttering) Form Work Design & Tolerance in Construction General Requirement Surface Treatment Inspection of Form Work Measurements Rate

127 127 127 127 129 130 131 132

5.3 5.3.1 5.3.2 5.3.3 5.3.4 5.3.5

Reinforcements General Requirements Welding of Bars Placing in Position Measurements Rate

133 133 133 133 135 135

5.4 5.4.1 5.4.2 5.4.3 5.4.4 5.4.5 5.4.6 5.4.7 5.4.8 5.4.9 5.4.10 5.4.11 5.4.12 5.4.13

Concreting Consistency Placing of Concrete Compaction Construction Joints Expansion Joints Curing Finishing Strength of Concrete Testing of Concrete Standard of Acceptance for Nominal Mix Measurements Tolerances Rate

135 135 135 136 136 137 137 137 138 139 139 142 144 144

5.5 5.5.1 5.5.2

Encasing Rolled Steel Sections General Requirements Wrapping

145 145 145 115

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

5.5.3 5.5.4 5.5.5 5.5.6

Form Work Concreting Measurements Rate

145 145 146 146

5.6 5.6.1 to 5.6.4 5.6.5 to 5.6.6 5.6.7 to 5.6.8

Precast Reinforced Concrete General Requirements Curing Marking

146 146 146 146

5.7 5.7.1 5.7.2 5.7.3

Precast Cement Concrete Jali Fixing Measurements Rate

147 147 147 147

5.8 5.8.0 5.8.1 5.8.2 5.8.3 5.8.4 5.8.5 5.8.6

Design Mix Definition Mix Design and Proportioning Standard Deviation Acceptance Criteria Cement Content of Concrete Water Cement Ratio and Slump Approval of Design Mix

147 147 147 147 148 148 148 149

5.9 5.9.1 5.9.2 5.9.3 5.9.4 5.9.5 5.9.6 5.9.7 5.9.8 5.9.9

Ready Mixed Concrete (As per IS 4926) Materials General Requirements Sampling and Testing of Ready - Mixed Concrete Information to be Supplied by the Purchaser Information to be Supplied by the Producer Production and Delivery Quality Control Order Processing Records

149 149 150 151 152 152 153 155 157 157

5.10 5.10.1 5.10.2

Placing Concrete by Pumping General Pumping Equipments

157 157 157

5.11 5.11.1 5.11.2 5.11.3 5.11.4 5.11.5

Guidelines for Field Practice General Precautions Submittals Sampling and Testing (Materials) Sampling and Testing for Quality Control of Fresh Concrete Sampling and Testing for Quality Control of Hardened Concrete

160 160 161 161 164 166

Appendix A

Cube Test for Compressive Strength of Concrete – Mandatory Lab Test

169

Appendix B

Additional Tests for Concrete

172

CPWD SPECIFICATIONS 2009

116

Appendix C

Register of Work Test of Concrete

176

Appendix D

List of Equipments required for Site Laboratory Annexure A – Sampling of Concrete Annexure B – Concrete Mix Information to be Supplied by the Purchaser Annexure C – Calibration and Weighing Equipment Accuracy Annexure D – Delivery Ticket Information

178 180 180

Fig. 5.1, 5.2 & 5.3

Typical set up of Steel Wall Form Work and Ties

183

Fig. 5.4 & 5.5

Typical Standard Units and Components of Form Work

186

Fig. 5.6 & 5.7

Typical Arrangements of Column Form Work.

188

Fig. 5.8

Typical details of Beam Head and Stiffener

190

Fig. 5.9

Typical details of Multi-Stage Shuttering

191

Fig. 5.10 to 5.23

Details of Expansion Joints

192

Fig. 5.24 & 5.25

Seismic Separation Joints, Details at Floor and Roof Level

197

Fig. 5.26

Construction Joints

198

Fig. 5.27 & 5.28

Encasing Rolling Steel Sections

199

117

181 182

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CPWD SPECIFICATIONS 2009

118

LIST OF MANDATORY TESTS Material

Clause

Test

Field/ laboratory test

Test procedure

1 Reinforced cement concrete (Nominal Mix)

2 5.4.1

3 (a) Slump test

4 Field/Lab

5 Appendix ‘D’ of Chapter 4

5.4.9.1

(b) Cube Test

Lab

Appendix ‘A’

119

Min, quantity of material for carrying out the test 6 (i) 5 cum in case of column (ii) 20 cum for slabs, beams and connected columns (iii) 20 cum for other R.C.C. work for all other small items and where R.C.C. done in a day is less than 5 cum test may be carried out as required by Engineerin-Charge (i) 5 cum in case of column (ii) 20 cum for slabs, beams and connected columns (iii) 20 cum for other R.C.C. work for all other small items and where R.C.C. done in a day is less than 5 cum test may be carried out as required by Engineerin-Charge

Frequency of testing

(i)

7 Every 5 cum of part thereof

(ii) Every 20 cum or part thereof

(iii) -Do-

(i)

Every 5 cum or part thereof

(ii) Every 20cum or part thereof

(iii) -Do-

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

1 Reinforced Cement Concrete (Design Mix)

2 Coarse Aggregates

3

4

5

Fresh Concrete

(a) Slump test

Field

Appendix ‘D’ of Chapter 4

Fresh Concrete

(b) Cube Test

Lab

Appendix ‘A’

Fine Aggregates Cement

Reinforced Cement Concrete (Ready Mix)

Coarse Aggregates Fine Aggregates Cement Fresh Concrete

(a) Slump test

CPWD SPECIFICATIONS 2009

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Appendix ‘D’ of Chapter 4

120

6 50 cum or part thereof & also on each change of source 50 cum or part thereof & also on each change of source 50 MT or on each change of source 10 cum

10 cum or part thereof

50 cum or part thereof & also on each change of source 50 cum or part thereof & also on each change of source 50 MT or on each change of source 10 cum

7

50 cum for R.C.C. work including in all other small location. R.C.C. done in a day is less than 50 cum test may be carried out as required by Engineer-in-Charge 50 cum or 10 batches of 5-7 cum each for R.C.C. work in all location taken together. R.C.C. done in a day is less than 50 cum test may be carried out as required by Engineer-in-Charge

50 cum for R.C.C. work including in all other small location. R.C.C. done in a day is less than 50 cum test may be carried out as required by Engineer-in-Charge

1

2 Fresh Concrete

3 (b) Cube Test

Steel for Reinforced cement concrete

5.1.3

(A) Physical Test and chemical tests

4 Lab

5 Appendix ‘A’

121

6 10 cum or part thereof

7 50 cum or 10 batches of 5-7 cum each for R.C.C. work in all location - taken together. R.C.C. done in a day is less than 50 cum test may be carried out as required by Engineerin-Charge (b) For (a) For consignconsignment below ment 100 tonnes over 100 tonnes (i) Under (i) under 10 mm 10 mm dia, dia, one one sample sample for each for 25 each tonnes 40 or part tonnes thereof or part (ii) 10 mm thereof to 16 mm dia (ii) 10 mm to 16 one mm, sample one for each sample 35 for tonnes each or part 45 thereof tonnes (iii) over 16 or part mm dia thereof one sample (iii) over 16 mm for each dia, 45 one tonnes sample or part for thereof each 50 tonnes or part thereof

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

LIST OF BUREAU OF INDIAN STANDARDS CODES Sl. No.

I.S. No.

Subject

1.

IS 226

Structural Steel

2.

IS 432 (Part I)

Specification for mild steel and medium tensile steel bars and hard drawn steel wire for concrete reinforcement part-I mild steel and medium tensile steel bars.

3.

IS 432 (Part II)

Specification for mild steel and medium tensile steel bars and hard drawn steel wire for concrete reinforcement – Part-II hard drawn steel wire.

4.

IS 456

Code of Practices for plain and Reinforced concrete.

5.

IS 516

Method of test for strength of concrete.

6.

IS 716

Specification for pentachlorophenol

7.

IS 1199

Method of sampling and analysis of concrete.

8.

IS 1200 (Part II)

Method of measurement of building and civil engineering work – concrete work

9.

IS 1200 (Part V)

Method of measurement of building and civil engineering work – concrete work (Part 5- Form work)

10.

IS 1566

Specification for hard drawn steel wire fabric for concrete requirement.

11.

IS 1599

Method for bend test

12.

IS 1343

Code of Practice for Prestressed Concrete

13.

IS 1608

Method for tensile testing of steel products

14.

IS 1786

Specification for high strength deformed steel and wires for concrete reinforcement.

15.

IS 1791

Specification for batch type concrete mixes

16.

IS 2502

Code of practice for bending and fixing of bars for concrete reinforcement.

17.

IS 2751

Recommended practice for welding of mild steel plain and deformed bars for reinforced construction.

18.

IS 4925

Batch plants specification for concrete batching and mixing plant

19.

IS 4926

Ready – Mixed Concrete

20.

IS 6523

Specification for precast reinforced concrete door, window frames

21.

IS 10262

Recommended guidelines for concrete mix design

22.

IS 13311 (Part I)

Indian standard for non-destructive testing of concrete. Method of test for ultrasonic pulse velocity

23.

IS 13311 (Part II)

Indian standard for non-destructive testing of concrete. Method of testing by rebound hammer.

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5.0 REINFORCED CEMENT CONCRETE WORK 5.0 GENERAL Reinforced cement concrete work may be cast-in-situ or Precast as may be directed by Engineer-inCharge according to the nature of work. Reinforced cement concrete work shall comprise of the following which may be paid separately or collectively as per the description of the item of work. (a) Form work (Centering and Shuttering) (b) Reinforcement (c) Concreting: (1– Cast-in-situ), (2 – Precast) 5.1 MATERIALS 5.1.1 Water, cement, fine and coarse aggregate shall be as specified under respective clauses of chapter 03 mortars and chapter 04 concrete work as applicable. 5.1.2 Fly Ash admixed cement concrete (FACC) and fly ash Blended cements in Cement Concrete (PPCC) in RCC structures. 5.1.2.0 Fly ash Blended Cements conforming to IS 1489 (Part I) may be used in RCC structures as per guidelines given below : 5.1.2.1 General (i) IS 456- 2000 Code of Practice for Plain and Reinforced Concrete (as amended up to date) shall be followed in regard to Concrete Mix Proportion and its production as under : (a) The concrete mix design shall be done as “Design Mix Concrete” as prescribed in clause-9 of IS 456 mentioned above. (b) Concrete shall be manufactured in accordance with clause 10 of above mentioned IS 456 covering quality assurance measures both technical and organizational, which shall also necessarily require a qualified Concrete Technologist to be available during manufacture of concrete for certification of quality of concrete. (ii) Minimum M -25 grade of concrete shall be used in all structural elements made with RCC both in load bearing and framed structure. (iii) The mechanical properties such as modulus of elasticity, tensile strength, creep and shrinkage of fly ash mixed concrete or concrete using fly ash blended cements (PPCs) are not likely to be significantly different and their values are to be taken same as those used for concrete made with OPC. (iv) To control higher rate of carbonation in early ages of concrete both in fly ash admixed as well as PPC based concrete, water/binder ratio shall be kept as low as possible, which shall be closely monitored during concrete manufacture. If necessitated due to low water/binder ratio, required workability shall be achieved by use of chloride free chemical admixtures conforming to IS 9103. The compatibility of chemical admixtures and super plasticizers with each set OPC, fly ash and /or PPC received from different sources shall be ensured by trials. (v) In environment subjected to aggressive chloride or sulphate attach in particular, use of fly ash admixed or PPC based concrete is recommended. In cases, where structural concrete is exposed to excessive magnesium sulphate, flyash substitution/content shall be limited to 18% by weight. Special type of cement with low C3A content may also be alternatively used. Durability criteria like minimum binder content and maximum water /binder ratio also need to be given due consideration in such environment.

123

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

(vi) Wet curing period shall be enhanced to a minimum of 10 days or its equivalent. In hot & arid regions, the minimum curing period shall be 14 days or its equivalent. 5.1.2.2 Use of Fly ash Admixed Cement Concrete (FACC) in RCC structures There shall be no bar on use of FACC in RCC structures subject to following additional conditions. (i) Fly ash shall have its chemical characteristics and physical requirements etc. conforming to IS 3812 (part I & II) and shall be duly certified. (ii) To ensure uniform blending of fly ash with cment in conformity with IS 456, a specific facility needs to be created at site with complete computerized automated process control to achieve design quality or with similar facility from Ready Mix Concrete (RMC) plants. (iii) As per IS 1489 (Part-I) maximum 35% of OPC by mass is permitted to be substituted with fly ash conforming to IS 3812 (Part –I) and same is reiterated. (iv) Separate storage for dry fly ash shall be provided. Storage bins or silos shall be weather proof and permit a free flow and efficient discharge of fly ash. The filter or dust control system provided in the bins or silos shall be of sufficient size to allow delivery of fly ash maintained at specified pressure to prevent undue emission of fly ash dust, which may interfere weighing accuracy. 5.1.2.3 Use of Fly Ash Blended Cements in Cement Concrete (PPCC) in RCC Structures (i) Subject to General Guidelines detailed out as above, PPC manufactured conforming to IS 1489 (Part-I) shall be treated at par with OPC for manufacture of Design Mix concrete for structural use in RCC. (ii) Till the time, BIS makes it mandatory to print the %age of fly ash on each bag of cement, the certificate from the PPC manufacture indicating the same shall be insisted upon before allowing use of such cements in works. (iii) While using PPC for structural concrete work, no further admixing of fly ash shall be permitted. 5.1.3 Steel for Reinforcement 5.1.3.1 The steel used for reinforcement shall be any of the following types: (a) Mild steel and medium tensile bars conforming to IS 432 (Part I) (b) High strength deformed steel bars conforming to IS 1786 (c) Hard drawn steel wire fabric conforming to IS 1566 (d) Structural steel conforming to Grade A of IS 2062 (e) Thermo-mechanically treated (TMT) Bars. 5.1.3.2 Elongation percent on gauge length is 5.65 piece.

A where A is the cross sectional areas of the test

5.1.3.3 Mild steel is not recommended for the use in structures located in earthquake zone subjected to severe damage and for structures subjected to dynamic loading (other than wind loading) such as railway and highway bridges. 5.1.3.4 Welding of reinforcement bars covered in this specification shall be done in accordance with the requirements of IS 2751. CPWD SPECIFICATIONS 2009

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Nominal mass/weight : The tolerance on mass/ weight for round and square bars shall be the percentage given in Table 5.1 of the mass/ weight calculated on the basis that the masses of the bar/ wire of nominal diameter and of density 7.85 kg/ cm3 or 0.00785 kg/mm3. TABLE 5.1 Tolerance on Nominal Mass Nominal size in mm (a) Upto and including 10 (b) Over 10, upto and including 16 (c) Over 16

Tolerance on the Nominal Mass per cent Batch Individual sample + Individual sample for coil (x) +7 -8 +8 +5

-6

+6

+3

-4

+4

+ for individual sample plus tolerance is not specified (x) for coil batch tolerance is not applicable Tolerance shall be determined in accordance with method given in IS 1786. 5.1.3.5 High strength deformed bars & wires shall conform to IS 1786. The physical properties for all sizes of steel bars are mentioned below in Table 5.2. TABLE 5.2 Sl. No

Property

(i)

(ii)

(iii)

(iv)

Fe 415 D

Fe 500 D

Fe 550 D

0.2 Per cent Proof 415.0 stress/ yield stress, Min, N/mm2

415.0

500.0

550.0

Elongation, per cent, 14.5 Min. on gauge length 5.65 A , where A is the corss-sectional area of the test piece. Tensile strength, Min 10 Per cent more than the actual 0.2 per cent proof stress/ yield stress but not less than 485.0 N/mm2

18.0

16.0

14.5

12 Per cent more than the actual 0.2 per cent proof stress/yield stress but not less than 500.0 N/mm2

10 Per cent more than the actual 0.2 per cent proof stress/ yield stress but not less than 565.0 N/mm2

8 Per cent more than the actual 0.2 per cent proof stress/yield stress but not less than 600.0 N/mm2

5

5

5

Total elongation at maximum force, percent, Min on gauge length 5.65 A , where A is the cross-sectional area of the test piece.

Fe 415

-

125

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

Tests: Selection and preparation of Test sample. All the tests pieces shall be selected by the Engineerin-Charge or his authorized representative either(a) From cutting of bars Or (b) If he so desires, from any bar after it has been cut to the required or specified size and the test piece taken from and any part of it. In neither case, the test pieces shall be detached from the bar or coil except in the presence of the Engineer-in-Charge or his authorized representative. The test pieces obtained in accordance with as above shall be full sections of the bars as rolled and subsequently cold worked and shall be subjected to physical tests without any further modifications. No deduction in size by machining or otherwise shall be permissible. No test piece shall be enacted or otherwise subject to heat treatment. Any straightening which a test piece may require shall be done cold. Tensile Test: 0.2% proof stress and percentage elongation – This shall be done as per IS 1608, read in conjunction with IS 226. RE- test: This shall be done as per IS 1786. Rebend test: This shall be done as per IS 1786. 5.1.3.6 Chemical composition of reinforcement bars shall be as per Table 5.3 as follows:TABLE 5.3 Constituent Carbon Sulphur Phosphorus Sulphur and Phosphorus

Fe 415 0.30 0.060 0.060 0.110

Maximum Per cent Fe 415 D Fe 500 D 0.25 0.25 0.045 0.040 0.045 0.040 0.085 0.075

Fe 550 D 0.25 0.040 0.040 0.075

5.1.3.7 Thermo Mechanically treated reinforcement bars: (a) There is no BIS code for TMT bars. The available code BIS 1786 pertains to HSD Bars. Therefore there should be no stipulation that TMT bars should conform to relevant BIS code. (b) The TMT bars are being produced under valid licence from either of the firms namely Tempcore, Thermex Evcon Turbo & Turbo Quench. These firms have acquired patents and are giving licences to various producers to produce TMT Bars. (c) The TMT bars shall conform to IS 1786 pertaining to Fe 415 D or Fe 500 D or Fe grade of steel as specified. (d) In design and construction of reinforced concrete building in seismic zone III and above, steel reinforcement of Grade Fe 415 D shall be used. However, high strength deformed steel bars, produced by thermomechanical treatment process of grade Fe 415, Fe 500 and Fe 550 having elongation more than 14.5. % and conform to other requirements of Fe 415 D, Fe 500 D and Fe 550 D respectively of IS 1786 may also be used for reinforcement. In future, latest provision of IS 456 and IS 13920 or any other relevant code as modified from time to time shall be applicable. 5.1.4 Stacking and Storage Steel for reinforcement shall be stored in such a way as to prevent distorting and corrosion. Care shall be taken to protect the reinforcement from exposure to saline atmosphere during storage, CPWD SPECIFICATIONS 2009

126

fabrication and use. It may be achieved by treating the surface of reinforcement with cement wash or by suitable methods. Bars of different classifications, sizes and lengths shall be stored separately to facilitate issue in such sizes and lengths to cause minimum wastage in cutting from standard length. 5.1.5 Identification Care shall also be taken to properly identify these bars at site. The staff shall be specially trained for looking for identification marks on these bars given by the manufacturers which are generally given colour code. It will be advisable to see that only one type/grade of bars are brought to site and used in the project after conducting tests for each lot. 5.2 FORM WORK (CENTRING & SHUTTERING) 5.2.1 Form Work Form work shall include all temporary or permanent forms or moulds required for forming the concrete which is cast-in-situ, together with all temporary construction required for their support. 5.2.2 Design & Tolerance in Construction Form work shall be designed and constructed to the shapes, lines and dimensions shown on the drawings with the tolerance given below. (a) Deviation from specified dimension of cross +12 mm section of columns and beams -6 mm (b) Deviation from dimensions of footings (i) Dimension in Plan (+ 50 mm ( -12 mm (ii) Eccentricity in plan 0.02 times the width of the footing in the direction of deviation but not more than 50 mm. (iii) Thickness + 0.05 times the specified thickness. (Note- These tolerance apply to concrete dimensions only, and not to positioning of vertical steel or dowels). 5.2.3 General Requirement It shall be strong enough to withstand the dead and live loads and forces caused by ramming and vibrations of concrete and other incidental loads, imposed upon it during and after casting of concrete. It shall be made sufficiently rigid by using adequate number of ties and braces, screw jacks or hard board wedges where required shall be provided to make up any settlement in the form work either before or during the placing of concrete. Form shall be so constructed as to be removable in sections in the desired sequence, without damaging the surface of concrete or disturbing other sections, care shall be taken to see that no piece is keyed into the concrete. 5.2.3.1 Material for Form Work (a) Propping and Centering : All propping and centering should be either of steel tubes with extension pieces or built up sections of rolled steel. 5.2.3.2 (a) Centering/Staging : Staging should be as designed with required extension pieces as approved by Engineer-in-Charge to ensure proper slopes, as per design for slabs/ beams etc. and as per levels as shown in drawing. All the staging to be either of Tubular steel structure with adequate bracings as approved or made of built up structural sections made form rolled structural steel sections. 127

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

(b) In case of structures with two or more floors, the weight of concrete, centering and shuttering of any upper floor being cast shall be suitably supported on one floor below the top most floor already cast. (c) Form work and concreting of upper floor shall not be done until concrete of lower floor has set at least for 14 days. 5.2.3.3 Shuttering: Shuttering used shall be of sufficient stiffness to avoid excessive deflection and joints shall be tightly butted to avoid leakage of slurry. If required, rubberized lining of material as approved by the Engineer-in-Charge shall be provided in the joints. Steel shuttering used or concreting should be sufficiently stiffened. The steel shuttering should also be properly repaired before use and properly cleaned to avoid stains, honey combing, seepage of slurry through joints etc. (a) Runner Joists: RSJ, MS Channel or any other suitable section of the required size shall be used as runners. (b) Assembly of beam head over props. Beam head is an adopter that fits snugly on the head plates of props to provide wider support under beam bottoms. (c) Only steel shuttering shall be used, except for unavoidable portions and very small works for which 12 mm thick water proofing ply of approved quality may be used. 5.2.3.4 Form work shall be properly designed for self weight, weight of reinforcement, weight of fresh concrete, and in addition, the various live loads likely to be imposed during the construction process (such as workmen, materials and equipment). In case the height of centering exceeds 3.50 metres, the prop may be provided in multi-stages. A typical detail of multistage shuttering is given in Fig. 5.9. 5.2.3.5 Camber: Suitable camber shall be provided in horizontal members of structure, especially in cantilever spans to counteract the effect of deflection. The form work shall be so assembled as to provide for camber. The camber for beams and slabs shall be 4 mm per metre (1 to 250 ) or as directed by the Engineer-in-Charge, so as to offset the subsequent deflection, For cantilevers the camber at free end shall be 1/50th of the projected length or as directed by the Engineer-in-Charge. 5.2.3.5.1 Typical arrangement of form work for ‘beams, columns and walls’ are shown in Figures 5.1 to 5.8 and form secured by wall ties is shown in Fig. 5.3. 5.2.3.6 Walls : The form faces have to be kept at fixed distance apart and an arrangement of wall ties with spacer tubes or bolts is considered best. A typical wall form with the components identified is given in Fig. 5.1, 5.2 & 5.3. The two shutters of the wall are to be kept in place by appropriate ties, braces and studs, some of the accessories used for wall form are shown in Fig. 5.3. 5.2.3.7 Removal of Form work (Stripping Time) : In normal circumstance and where various types of cements are used, forms, may generally be removed after the expiry of the following periods: Type of Form work

Minimum period Before Striking Form work for OPC 33 grade (a) Vertical form work to columns, 16-24 h walls, beams

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128

Minimum period Minimum period Before Striking Before Striking Form work for OPC Form work for 43 grade PPC 16-24 h 24-36 h

Type of Form work

Minimum period Before Striking Form work for OPC 33 grade (b) Soffit form work to slabs (Props to 3 days be refixed immediately after removal of formwork) (c) Soffit form work to beams (Props 7 days to be refixed immediately after removal of formwork (d) Props to slabs: (1) Spanning upto 4.5m 7 days (2) Spanning over 4.5m 14 days (e) Props to beams and arches: (1) Spanning upto 6m (2) Spanning over 6m

14 days 21 days

Minimum period Minimum period Before Striking Before Striking Form work for OPC Form work for 43 grade PPC 3 days 4 days 7 days

10 days

7 days 14 days

10 days 20 days

14 days 21 days

20 days 30 days

Note 1:

For other types of cement, the stripping time recommended for ordinary Portland cement may be suitably modified. Generally If Portland pozzolana or low heat cement or OPC with direct addition of fly ash has been used for concrete, the stripping time will be 10/7 of the period stated for OPC with 43 grade cement above.

Note 2:

The number of props left under, their sizes and disposition shall be such as to be able to safely carry the full dead load of the slabs, beam or arch as the case may be together with any live load likely to occur during curing or further construction.

Note 3:

For rapid hardening cement, 3/7 of above periods for OPC 33 grade will be sufficient in all cases except for vertical side of slabs, beams and columns which should be retained for at least 24 hours.

Note 4:

In case of cantilever slabs and beams, the centering shall remain till structures for counter acting or bearing down have been erected and have attained sufficient strength.

Note 5:

Proper precautions should be taken to allow for the decrease in the rate of hardening that occurs with all types of cement in cold weather and accordingly stripping time shall be increased.

Note 6:

Work damaged through premature or careless removal of forms shall be reconstructed within 24 hrs.

5.2.4 Surface Treatment 5.2.4.1 Oiling the Surface : Shuttering gives much longer service life if the surfaces are coated with suitable mould oil which acts both as a parting agent and also gives surface protections. A typical mould oil is heavy mineral oil or purified cylinder oil containing not less than 5% pentachlorophenol conforming to IS 716 well mixed to a viscosity of 70-80 centipoises. After 3-4 uses and also in cases when shuttering has been stored for a long time, it should be recoated with mould oil before the next use.

129

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

The second categories of shuttering oils / leavening agents are Polymer based water soluble Compounds. They are available as concentrates and when used diluted with water in the ratio of 1:20 or as per manufacturer specifications. The diluted solution is applied by brush applications on the shuttering both of steel as well as ply wood. The solution is applied after every use. 5.2.4.2 The design of form work shall conform to sound Engineering practices and relevant IS codes. 5.2.5 Inspection of Form Work The completed form work shall be inspected and approved by the Engineer-in-Charge before the reinforcement bars are placed in position. Proper form work should be adopted for concreting so as to avoid honey combing, blow holes, grout loss, stains or discoloration of concrete etc. Proper and accurate alignment and profile of finished concrete surface will be ensured by proper designing and erection of form work which will be approved by Engineer-in-Charge. Shuttering surface before concreting should be free from any defect/ deposits and full cleaned so as to give perfectly straight smooth concrete surface. Shuttering surface should be therefore checked for any damage to its surface and excessive roughness before use. 5.2.5.1 Erection of Form Work (Centering and shuttering): Following points shall be borne in mind while checking during erection. (a) Any member which is to remain in position after the general dismantling is done, should be clearly marked. (b) Material used should be checked to ensure that, wrong items/ rejects are not used. (c) If there are any excavations nearby which may influence the safety of form works, corrective and strengthening action must be taken. (d) (i) The bearing soil must be sound and well prepared and the sole plates shall bear well on the ground. (ii) Sole plates shall be properly seated on their bearing pads or sleepers. (iii) The bearing plates of steel props shall not be distorted. (iv) The steel parts on the bearing members shall have adequate bearing areas. (e) Safety measures to prevent impact of traffic, scour due to water etc. should be taken. Adequate precautionary measures shall be taken to prevent accidental impacts etc. (f) Bracing, struts and ties shall be installed along with the progress of form work to ensure strength and stability of form work at intermediate stage. Steel sections (especially deep sections) shall be adequately restrained against tilting, over turning and form work should be restrained against horizontal loads. All the securing devices and bracing shall be tightened. (g) The stacked materials shall be placed as catered for, in the design. (h) When adjustable steel props are used. They should: 1. be undamaged and not visibly bent. 2. have the steel pins provided by the manufacturers for use. 3. be restrained laterally near each end. 4. have means for centralizing beams placed in the forkheads. (i) Screw adjustment of adjustable props shall not be over extended. CPWD SPECIFICATIONS 2009

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(j) Double wedges shall be provided for adjustment of the form to the required position wherever any settlement/ elastic shorting of props occurs. Wedges should be used only at the bottom end of single prop. Wedges should not be too steep and one of the pair should be tightened/ clamped down after adjustment to prevent shifting. (k) No member shall be eccentric upon vertical member. (l) The number of nuts and bolts shall be adequate. (m) All provisions of the design and/or drawings shall be complied with. (n) Cantilever supports shall be adequate. (o) Props shall be directly under one another in multistage constructions as far as possible. (p) Guy ropes or stays shall be tensioned properly. (q) There shall be adequate provision for the movements and operation of vibrators and other construction plant and equipment. (r) Required camber shall be provided over long spans. (s) Supports shall be adequate, and in plumb within the specified tolerances. 5.2.6 Measurements 5.2.6.1 General : The form work shall include the following: (a) Splayed edges, notching, allowance for overlaps and passing at angles, sheathing battens, strutting, bolting, nailing, wedging, easing, striking and removal. (b) All supports, struts, braces, wedges as well as mud sills, piles or other suitable arrangements to support the form work. (c) Bolts, wire, ties, clamps, spreaders, nails or any other items to hold the sheathing together. (d) Working scaffolds, ladders, gangways, and similar items. (e) Filleting to form stop chamfered edges of splayed external angles not exceeding 20mm wide to beams, columns and the like. (f) Where required, the temporary openings provided in the forms for pouring concrete, inserting vibrators, and cleaning holes for removing rubbish from the interior of the sheathing before pouring concrete. (g) Dressing with oil to prevent adhesion and (h) Raking or circular cutting 5.2.6.2 Classification of Measurements : Where it is stipulated that the form work shall be paid for separately, measurements shall be taken of the area of shuttering in contact with the concrete surface. Dimensions of the form work shall be measured correct to a cm. The measurements shall be taken separately for the following. (a) Foundations, footings, bases of columns etc. and for mass concrete 131

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

(b) Walls (any thickness) including attached pilasters, buttresses, plinth and string courses etc. (c) Suspended floors, roofs, landings, shelves and their supports and balconies. (d) Lintels, beams, plinth beams, girders, bressummers and cantilevers. (e) Columns, pillars, piers, abutments posts and struts. (f) Stairs (excluding landings) except spiral staircase. (g) Spiral staircases (including landings). (h) Arches,Domes, vaults, shells roofs, arch ribs, curvilinear shaped folded plates (i) Extra for arches, domes, vaults exceeding 6 m span other than curvilinear shaped (j) Chimneys and shafts. (k) Well steining. (l) Vertical and horizontal fins individually or forming box, louvers and bands.facias and eaves board (m) Waffle or ribbed slabs. (n) Edges of slabs and breaks in floors and walls (to be measured in running metres where below 200 mm in width or thickness). (o) Cornices and mouldings. (p) Small surfaces, such as cantilevers ends, brackets and ends of steps, caps and boxes to pilasters and columns and the like. (q) Chullah hoods, weather shades, chajjas, corbels etc. including edges and (r) Elevated water reservoirs. 5.2.6.3 Centering, and shuttering where exceeding 3.5 metre height in one floor shall be measured and paid for separately. 5.2.6.4 Where it is not specifically stated in the description of the item that form work shall be paid for separately, the rate of the RCC item shall be deemed to include the cost of form work. 5.2.6.5 No deductions from the shuttering due to the openings/ obstructions shall be made if the area of each openings/ obstructions does not exceed 0.4 square metre. Nothing extra shall be paid for forming such openings. 5.2.6.6 Form work of elements measured under categories of arches, arch ribs, domes, spiral staircases, well steining, shell roofs, curvilinear folded plates & curvilinear eaves board, circular shafts & chimneys shall not qualify for extra rate for circular work. 5.2.6.7 Extra for circular work shall be admissible for surfaces circular or curvilinear in plan or in elevation beyond the straight edge of supporting beam in respective mode of measurement. However, there may be many different types of such structures. In such cases, extra payment shall be made judiciously after deducting areas where shuttering for circular form work is not involved. 5.2.7 Rate The rate of the form work includes the cost of labour and materials required for all the operations described above. CPWD SPECIFICATIONS 2009

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5.3 REINFORCEMENTS 5.3.1 General Requirements Steel conforming to para 5.1.3 for reinforcement shall be clear and free from loose mill scales, dust, loose rust, coats of paints, oil or other coating which may destroy or reduce bond. It shall be stored in such a way as to avoid distortion and to prevent deterioration and corrosion. Prior to assembly of reinforcement on no account any oily substance shall be used for removing the rust. 5.3.1.1 Assembly of Reinforcement : Bars shall be bent correctly and accurately to the size and shape as shown in the detailed drawing or as directed by Engineer-in-Charge. Preferably bars of full length shall be used. Necessary cutting and straightening is also included. Overlapping of bars, where necessary shall be done as directed by the Engineer-in-Charge. The overlapping bars shall not touch each other and these shall be kept apart with concrete between them by 25mm or 11/4 times the maximum size of the coarse aggregate whichever is greater. But where this is not possible, the overlapping bars shall be bound together at intervals not exceeding twice the dia. of such bars with two strands annealed steel wire of 0.90 mm to 1.6 mm twisted tight. The overlaps/ splices shall be staggered as per directions of the Engineer-in-Charge. But in no case the overlapping shall be provided in more than 50% of cross sectional area at one section. 5.3.1.2 Bonds and Hooks Forming End Anchorages: Reinforcement shall be bent and fixed in accordance with procedure specified in IS 2502, code of practice of bending and fixing of bars for concrete reinforcement. The details of bends and hooks are shown below for guidance. (a) U-Type Hook In case of mild steel plain bars standard U type hook shall be provided by bending ends of rod into semicircular hooks having clear diameter equal to four times the diameter of the bar. Note: In case of work in seismic zone, the size of hooks at the end of the rod shall be eight times the diameter of bar or as given in the structural drawings. (b) Bends Bend forming anchorage to a M.S. plain bar shall be bent with and internal radius equal to two times the diameter of the bar with a minimum length beyond the bend equal to four times the diameter of the bar. 5.3.1.3 Anchoring Bars in Tension : Deformed bars may be used without end anchorages provided, development length equipment is satisfied. Hooks should normally be provided for plain bars in tension. Development length of bars will be determined as per IS: 456. 5.3.1.4 Anchoring Bars in Compression : The anchorage length of straight bar in compression shall be equal to the ‘Development length’ of bars in compression as specified in IS: 456. The projected length of hooks, bend and straight lengths beyond bend, if provided for a bar in compression, shall be considered for development length. 5.3.1.5 Binders, stirrups, links etc. : In case of binders, stirrups, links etc. the straight portion beyond the curve at the end shall be not less than eight times and nominal size of bar. 5.3.2 Welding of Bars Wherever facility for electric arc welding or gas pressure welding is available, welding of bars shall be done in lieu of overlap. The location and type of welding shall be got approved by the Engineer-inCharge. Welding shall be as per IS 2751 and 9417. 5.3.3 Placing in Position 5.3.3.1 Fabricated reinforcement bars shall be placed in position as shown in the drawings or as directed by the Engineer-in-charge. The bars crossing one another shall be tied together at every intersection with two strands of annealed steel wire 0.9 to 1.6 mm thickness twisted tight to make the skeleton of the steel work rigid so that the reinforcement does not get displaced during deposition of concrete. 133

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Tack welding in crossing bars shall also be permitted in lieu of binding with steel wire if approved by Engineer-in-Charge. 5.3.3.2 The bars shall be kept in correct position by the following methods: (a) In case of beam and slab construction pre-cast cover blocks in cement mortar 1:2 (1 cement : 2 coarse sand) about 4x4 cm section and of thickness equal to the specified cover shall be placed between the bars and shuttering, so as to secure and maintain the requisite cover of concrete over reinforcements. (b) In case of cantilevered and doubly reinforced beams of slabs, the vertical distance between the horizontal bars shall be maintained by introducing chairs, spacers or support bars of steel at 1.0 mere or at shorter spacing to avoid sagging. (c) In case of columns and walls, the vertical bars shall be kept in position by means of timber templates with slots accurately cut in them: or with clock of cement mortar 1:2 (1 cement: 2 coarse sand) of required size suitable tied to the reinforcement to ensure that they are in correct position during concreting. (d) In case of other R.C.C. structure such as arches, domes, shells, storage tanks etc. a combination of cover blocks, spacers and templates shall be used as directed by Engineer-in-Charge. 5.3.3.3 Tolerance on Placing of Reinforcement : Unless otherwise specified by the Engineer-inCharge, reinforcement shall be placed within the following tolerances: (a) For effective depth, 200 mm or less (b) For effective depth, more than 200 mm

Tolerance in spacing +10 mm + 15 mm

5.3.3.4 Bending at Construction Joints : Where reinforcement bars are bent aside at construction joints and afterwards bent back into their original position care should be taken to ensure that at no time the radius of the bend is less than 4 bar diameters for plain mild steel or 6 bar diameter for deformed bars. Care shall also be taken when bending back bars to ensure that the concrete around the bar is not damaged. 5.3.3.5 Cover : The minimum nominal cover to meet durability requirements shall be as under:Exposure Mild Moderate Severe Very severe Extreme Notes :

Nominal Concrete cover in mm not less than 20 30 45 50 75

1. For main reinforcement upto 12 mm diameter bar for mild exposure the nominal cover may be reduced by 5 mm. 2. Unless specified otherwise, actual concrete cover should not deviate from the required nominal cover by + 10 mm. 3. For exposure condition ‘severe’ and ‘very severe’ reduction of 5 mm may be made, where concrete grade is M35 and above. 4. Nominal cover to meet specified period of fire resistance shall not be less than as given in Table 16A of IS 456.

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5.3.4 Measurement Reinforcement including authorized spacer bars and lappages shall be measured in length of different diametre, as actually (not more than as specified in the drgs.) used in the work nearest to a centimetre and their weight calculated on the basis of standard weight given in Table 5.4 below. In case actual unit weight of the bars is less than standard unit weight, but within variation, in such cases weight of reinforcement shall be calculated on the basis of actual unit weight. Wastage and unauthorized overlaps shall not be paid for. Annealed steel wire required for binding or tack welding shall not be measured, its cost being included in the rate of reinforcement. Where tack welding is used in lieu of binding, such welds shall not be measured. Chairs separators etc. shall be provided as directed by the Engineer-in-Charge and measured separately and paid for. TABLE 5.4 Cross Sections Area and Mass of Steel Bar Nominal Size mm 6 8 10 12 16 20 25 28 32 36 40

Cross sectional Area Sq.mm 28.3 50.3 78.6 113.1 201.2 314.3 491.1 615.8 804.6 1018.3 1257.2

Mass per metre Run Kg. 0.222 0.395 0.617 0.888 1.58 2.47 3.85 4.83 6.31 7.99 9.86

Note: These are as per clause 6.2 of IS 1786. 5.3.5 Rate The rate for reinforcement shall include the cost of labour and materials required for all operations described above such as cleaning of reinforcement bars, straightening, cutting, hooking bending, binding, placing in position etc. as required or directed including tack welding on crossing of bars in lieu of binding with wires. 5.4 CONCRETING 5.4.0 The concrete shall be as specified under chapter 4 concrete work. The proportion by volume or by the weight of ingredients shall be as specified. 5.4.1 Consistency The concrete which will flow sluggishly into the forms and around the reinforcement without any segregation of coarse aggregate from the mortar shall be used. The consistency shall depend on whether the concrete is vibrated on or hand tamped, it shall be determined by slump test as prescribed in sub-head “concrete” under workability – requirement. 5.4.2 Placing of Concrete 5.4.2.1 Concreting shall be commenced only after Engineer-in-Charge has inspected the centering, shuttering and reinforcement as placed and passed the same. Shuttering shall be clean and free from all shavings, saw dust, pieces of wood, or other foreign material and surfaces shall be treated as prescribed in 5.2.4. 135

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5.4.2.2 In case of concreting of slab and beams, wooden plank or cat walks of chequerred MS plated or bamboo chalies or any other suitable material supported directly on the centering by means of wooden blocks or lugs shall be provided to convey the concrete to the place of deposition without disturbing the reinforcement in any way. Labour shall not be allowed to walk over the reinforcement. 5.4.2.3 In case of columns and wall, it is desirable to place concrete without construction joints. The progress of concreting in the vertical direction, shall be restricted to one metre per hour. 5.4.2.4 The concrete shall be deposited in its final position in a manner to preclude segregation of ingredients. In deep trenches and footings concrete shall be placed through chutes or as directed by the Engineer-in-Charge. In case of columns and walls, the shuttering shall be so adjusted that the vertical drop of concrete is not more than 1.5 metres at a time. 5.4.2.5 During cold weather, concreting shall not be done when the temperature falls below 4.50C. The concrete placed shall be protected against frost by suitable covering. Concrete damaged by frost shall be removed and work redone. 5.4.2.6 During hot weather precaution shall be taken to see that the temperature of wet concrete does not exceed 38ºC. No concrete shall be laid within half an hour of the closing time of the day, unless permitted by the Engineer-in-Charge. 5.4.2.7 It is necessary that the time between mixing and placing of concrete shall not exceed 30 minutes so that the initial setting process is not interfered with. 5.4.3 Compaction It shall be as specified in sub-head of Concrete Work of this specification. 5.4.3.1 Concrete shall be compacted into dense mass immediately after placing by means of mechanical vibrators designed for continuous operations complying with IS 2505, IS 2506, IS 2514 and IS 4656. The Engineer-in-Charge may however relax this condition at his discretion for certain items depending on the thickness of the members and feasibility of vibrating the same and permit hand compaction instead. Hand compaction shall be done with the help of tamping rods so that concrete is thoroughly compacted and completely worked around the reinforcement, embedded fixtures, and into corners of the form. The layers of concrete shall be so placed that the bottom layer does not finally set before the top layer is placed. The vibrators shall maintain the whole of concrete under treatment in an adequate state of agitation; such that de-aeration and effective compaction is attained at a rate commensurate with the supply of concrete from the mixers. The vibration shall continue during the whole period occupied by placing of concrete, the vibrators being adjusted so that the centre of vibrations approximates to the centre of the mass being compacted at the time of placing. 5.4.3.2 Concrete shall be judged to be properly compacted, when the mortar fills the spaces between the coarse aggregate and begins to cream up to form an even surface. When this condition has been attained, the vibrator shall be stopped in case of vibrating tables and external vibrators. Needle vibrators shall be withdrawn slowly so as to prevent formation of loose pockets in case of internal vibration. In case both internal and external vibrators are being used, the internal vibrator shall be first withdrawn slowly after which the external vibrators shall be stopped so that no loose pocket is left in the body of the concrete. The specific instructions of the makers of the particular type of vibrator used shall be strictly complied with. Shaking of reinforcement for the purpose of compaction should be avoided. Compaction shall be completed before the initial setting starts, i.e. with 30 minutes of addition of water to the dry mixture. 5.4.4 Construction joints 5.4.4.1 Concreting shall be carried out continuously upto the construction joints, the position and details of which shall be as shown in structural drawing or as indicated in Fig. 5.26 or as directed by EngineerCPWD SPECIFICATIONS 2009

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in-Charge. Number of such joints shall be kept to minimum. The joints shall be kept at places where the shear force is the minimum. These shall be straight and shall be at right angles to the direction of main reinforcement. Construction joints should comply with IS 11817. 5.4.4.2 In case of columns the joints shall be horizontal and 10 to 15 cm below the bottom of the beam running into the column head. The portion of the column between the stepping off level and the top of the slab shall be concreted with the beam. 5.4.4.3 When stopping the concrete on a vertical plane in slabs and beams, and approved stop board (see Fig. 26C) shall be placed with necessary slots for reinforcement bars or any other obstruction to pass the bars freely without bending. The construction joints shall be keyed by providing a triangular or trapezoidal fillet nailed on the stopboard. Inclined or feather joints shall not be permitted. Any concrete flowing through the joints of stopboard shall be removed soon after the initial set. When concrete is stopped on a horizontal plane, the surface shall be roughened and cleaned after the initial set. 5.4.4.4 When the work has to be resumed, the joint shall be thoroughly cleaned with wire brush and loose particles removed. A coat of neat cement slurry at the rate of 2.75 kg of cement per square metre shall then be applied on the roughened surface before fresh concrete is laid. 5.4.5 Expansion Joints Expansion joints shall be provided as shown in the structural drawings or as indicated in Fig. 5.10 to 5.25 or as directed by Engineer-in-Charge, for the purpose of general guidance. However it is recommended that structures exceeding 45 m in length shall be divided by one or more expansion joints. The filling of these joints with bitumen filler, bitumen felt or any such material and provision of copper plate, etc. shall be paid for separately in running metre. The measurement shall be taken two places of decimal stating the depth and width of joint. 5.4.6 Curing After the concrete has begun to harden i.e. about 1 to 2 hours after its laying, it shall be protected from quick drying by covering with moist gunny bags, sand, canvass Hessian or any other material approved by the Engineer-in-Charge. After 24 hours of laying of concrete, the surface shall be cured by ponding with water for a minimum period of 7 days from the date of placing of concrete in case of OPC and at least 10 days where mineral admixtures or blended cements are used. The period of curing shall not be less than 10 days for concrete exposed to dry and hot weather condition. 5.4.7 Finishing 5.4.7.1 In case of roof slabs the top surface shall be finished even and smooth with wooden trowel, before the concrete begins to set. Sprinkling of dry cement while finishing shall not be resorted to. 5.4.7.2 Immediately on removal of forms, the R.C.C. work shall be examined by the Engineer-in-Charge, before any defects are made good. (a) The work that has sagged or contains honey combing to an extent detrimental to structural safety or architectural concept shall be rejected as given in para 5.4.9.4 for visual inspection test. (b) Surface defects of minor nature may be accepted. On acceptance of such a work by the Engineer-in-Charge, the same shall be rectified as follows: 1. Surface defects which require repair when forms are removed, usually consist of bulged due to movement of forms, ridges at form joints, honey-combed areas, damage resulting from the stripping of forms and bolt holes, bulges and ridges are removed by careful chipping or tooling and the surface is then rubbed with a grinding stone. Honey-combed and other defective areas must be chipped out, the edges being cut as straight as possible and perpendicularly to the surface, or preferably slightly under cut to provide a key at the edge of the patch. 137

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2. Shallow patches are first treated with a coat of thin grout composed of one part of cement and one part of fine sand and then filled with mortar similar to that used in the concrete. The mortar is placed in layers not more than 10mm thick and each layer is given a scratch finish to secure bond with the succeeding layer. The last layer is finished to match the surrounding concrete by floating, rubbing or tooling on formed surfaces by pressing the form material against the patch while the mortar is still plastic. 3. Large and deep patches require filling up with concrete held in place by forms. Such patches are reinforced and carefully dowelled to the hardened concrete. 4. Holes left by bolts are filled with mortar carefully packed into places in small amounts. The mortar is mixed as dry as possible, with just enough water so that it will be tightly compacted when forced into place. 5. Tiered holes extending right through the concrete may be filled with mortar with a pressure gun similar to the gun used for greasing motor cars. 6. Normally, patches appear darker than the surrounding concrete, possibly owing to the presence on their surface of less cement laitance. Where uniform surface colour is important, this defect shall be remedied by adding 10 to 20 percent of white Portland cement to the patching mortar, the exact quantity being determined by trial. 7. The same amount of care to cure the materials in the patches should be taken as with the whole structure. Curing must be started as soon as possible, after the patch is finished to prevent early drying. Damp Hessian may be used but in some locations it may be difficult to hold it in place. A membrane curing compound in these cases will be most convenient. (c) The exposed surface of R.C.C. work shall be plastered with cement mortar 1:3 (1 cement : 3 fine sand) of thickness not exceeding 6 mm to give smooth and even surface true to line and form. Any RCC surface which remains permanently exposed to view in the completed structure, shall be considered exposed surfaced for the purpose of this specification. Where such exposed surface exceeding 0.5 sqm in each location is not plastered with cement mortar 1:3 (1 cement : 3 fine sand) 6 mm thick, necessary deduction shall be made for plastering not done. (d) The surface which is to receive plaster or where it is to be joined with brick masonry wall, shall be properly roughened immediately after the shuttering is removed, taking care to remove the laitance completely without disturbing the concrete. The roughening shall be done by hacking. Before the surface is plastered, it shall be cleaned and wetted so as to give bond between concrete and plaster. RCC work shall be done carefully so that the thickness of plaster required for finishing the surface is not more than 6 mm. (e) The surface of RCC slab on which the cement concrete or mosaic floor is to be laid shall be roughened with brushes while the concrete is green. This shall be done without disturbing the concrete. 5.4.8 Strength of Concrete The compressive strength on the work tests for different mixed shall be as given in Table 5.5 below:-

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TABLE 5.5 Concrete Mix (Nominal Mix on Volume basis)

Compressive Strength in (Kg/ sq cm) 7 days’ 210 175 140

1:1:2 1:1.5:3 1:2:4

28 days’ 315 265 210

5.4.9 Testing of Concrete 5.4.9.0 Regular mandatory tests on the workability of the fresh concrete shall be done to achieve the specified compressive strength of concrete. These will be of two types (a) Mandatory Lab, Test (b) Mandatory Field Test Results of Mandatory Field Test will prevail over mandatory Lab. Test. 5.4.9.1 Cube Test for Compressive Strength of Concrete - Mandatory Lab Test : Mandatory tests shall be carried out as prescribed in Appendix A of Chapter 5. 5.4.9.2 Additional Test : Additional test, if required, shall be carried out as prescribed in Appendix B of Chapter 5. 5.4.9.3 Slump Test : This test shall be carried out as prescribed in sub-head 4 of concrete. 5.4.9.4 Visual Inspection Test : The concrete will be inspected after removal of the form work as described in para 5.4.7.2 The question of carrying out mandatory test or other tests described in Appendix A and B (para 5.4.9.1 and 5.4.9.2) will arise only after satisfactory report of visual inspection. The concrete is liable to be rejected if: (i) It is porous or honeycombed as per para 5.4.7.2 (a). (ii) Its placing has been interrupted without providing a proper construction joint. (iii) The reinforcement has been displaced beyond tolerance specified or construction tolerances have not been met. However, the hardened concrete may be accepted after carrying out suitable remedial measures to the satisfaction of the Engineer-in-Charge at the risk and cost of the contractor. 5.4.10 Standard of Acceptance – for Nominal Mix 5.4.10.1 Mandatory Lab. Test : For concrete sampled and tested as prescribed in Appendix A of Chapter 5, the following requirement shall apply. 5.4.10.2 Out of six sample cubes, three cubes shall be tested at 7 days and remaining three cubes at 28 days. 5.4.10.3 7 days’ Tests Sampling: The average of the strength of three specimen shall be accepted as the compressive strength of the concrete provided the variation in strength of individual specimen is not more than + 15% of the average. Difference between the maximum and minimum strength should not exceed 30% of average strength of three specimen. If the difference between maximum and minimum strength exceeds 30% of the average strength, then 28 days’ test shall have to be carried out.

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Strength: If the actual average strength of sample accepted in para ‘sampling’ above is equal to or higher than specified strength upto +15% then strength of the concrete shall be considered in order. In case the actual average strength of sample accepted in the above para is lower than the specified or higher by more than 15% then 28 days’ test shall have to be carried out to determine the compressive strength of concrete cubes. 5.4.10.4 28 days’ Test (a) The average of the strength of three specimen be accepted as the compressive strength of the concrete provided the strength of any individual cube shall neither be less than 70% nor higher than 130% of the specified strength. (b) If the actual average strength of accepted sample exceeds specified strength by more than 30% the Engineer-in-Charge, if he so desires, may further investigate the matter. However, if the strength of any individual cube exceeds more than 30% of specified strength, it will be restricted to 130% only for computation of strength. (c) If the actual average strength of accepted sample is equal to or higher than specified strength upto 30% then strength of the concrete shall be considered in order and the concrete shall be accepted at full rates. (d) If the actual average strength of accepted sample is less than specified strength but not less than 70% of the specified strength, the concrete may be accepted at reduced rate at the discretion of Engineer-in-Charge (see para 5.4.13.2). (e) If the actual average strength of accepted sample is less than 70% of specified strength, the Engineer-in-Charge shall reject the defective portion of work represented by sample and nothing shall be paid for the rejected work. Remedial measures necessary to retain the structure shall be taken at the risk and cost of contractor. If, however the Engineer-in-Charge so desires, he may order additional tests (See Appendix B of Chapter 5) to be carried out to ascertain if the structure can be retained. All the charges in connection with these additional tests shall be borne by the contractor. 5.4.10.5 Acceptance Criteria of Field Test (Additional Test – Not Mandatory) (A) Preparation of Standard Test Cubes for calibration of Rebound Hammer at site (a) In the beginning the standard test cubes of the specified mix shall be prepared by field units before undertaking any concrete work in each project. (b) At least 18 standard cubes necessary for formation of one specimen of specified mix, shall be cast by site staff well in advance. From these 18 cubes any 3 cubes may be selected at random to be tested for crushing strength of 7 days. The crushing strength obtained should satisfy the specified strength for the mix as per specification or agreement. If the strength is satisfactory then the remaining cube will form the standard samples for calibration of rebound hammer. In case of failure, the site staff should totally reject the samples and remove them also and then make another set of samples by fresh mixing or alternatively, out of the remaining 15 cubes, 3 cubes will be tested on 28 days. If the 28 days’ tests are found satisfactory then remaining 12 cubes will form the standard sample for calibration at 28 days’ strength otherwise all samples shall be rejected and whole procedure repeated to form a fresh specimen. All the results shall be recorded in a register. (c) No concreting will be allowed unless the standard specimen cubes are obtained. The criteria for acceptance and calibration of hammer will be 28 days’ strength. The 7 days’ strength is only to facilitate the work to start. CPWD SPECIFICATIONS 2009

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(d) No work (for the concrete cast between 8th and 28th day) shall be allowed to be paid unless 28 days’ cube strength is obtained. For the concrete cast between 8th and 28th day, the decision to make the payment may be taken by the Engineer-in-charge on the basis of existing criteria. Concrete work will be rejected if 28 days’ strength falls short as per acceptance criteria. No further work will be allowed till the acceptable standard cubes are obtained. (e) Frequency: it will be once in each quarter or as per the direction and discretion of Engineerin-Charge. Whenever the acceptance criteria is changed or concrete mix or type of cement is changed or Engineer-in-Charge feels it necessary for recorded reasons with the approval of the authority according to technical sanction, fresh specimen shall be prepared. (B) Calibration of Hammer (a) Simultaneously, same three cubes to be tested on 28 days as referred in para A (b) above shall be used to correlate the compressive strength of their concrete with rebound number as per procedure described in para 5.2 of the IS 13311 (Part 2) “Indian standard for nondestructive testing of concrete Method of test by rebound hammer which is given below in para B (b). The average of values of the rebound number (minimum readings) obtained in respect of same three cubes passing on 28 days’ work test shall form the datum reference for remaining cubes for the strength of cubes. (b) The concrete cubes specimens are held in a compression testing machine under a fixed load, measurements of rebound hammer taken and then compressive strength determined as per IS 516. The fixed load required is of the order of 7 N/mm2 when the impact energy of the hammer is about 2.2 NM. If the specimen are wet cured, they should be removed from wet storage & kept in the laboratory atmosphere for about 24 hours before testing. Only the vertical faces of the cubes as cast should be tested for rebound number. At least nine readings should be taken on each of the three vertical faces accessible in the compression testing machine when using rebound hammers. The points of impact in the specimen must not be nearer than 20 mm from the edge & should not be less than 20 mm from each other. The same points must not be impacted more than once. (c) The rebound number of hammer will be determined on each of the remaining (18-3-3=12) cubes. Whenever the rebound number of hammer of any individual cube varies by more than +25% form the datum readings referred to in para B (a) above, that cube will be excluded and will not be considered for standard specimen cubes for calibration. It must be ensured that at least 8 cubes out of 12 that is 66.67% are within the permissible range of variation of rebound number i.e. +25% or otherwise whole procedure shall have to be repeated and fresh specimen prepared. These 8 cubes will form one standard sample in the beginning before commencement of work and shall be kept carefully for the visiting officers who will calibrate their hammers on these cubes. (d) This calibration will be done by field staff with their hammer and then chart of calibration giving the details of the average readings, date & month of casting, mix of the concrete etc. shall be prepared and signed by Engineer-in-Charge and will be duly preserved for future reference as and when required. (C) Preservation of Cubes at site Standard sample cubes cast shall be carefully preserved at site under the safe custody of AE or his representative for making them available together with the charts, to the officers of QCTA/CTE or any other senior departmental officer, during their inspection of the work. They will calibrate their hammer on these cubes if required. 141

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(D) Testing at Site (D-1) Testing Equipments (D-2)

Testing will be done generally by non-destructive methods like rebound hammers etc. Each field Division/ Sub Division/ Unit will purchase rebound hammers and keep them in working order at work site. The testing will be done only by hammers which are duly calibrated.

(D-3)

The relative strength of actual field work will be tested with reference to strength of these standard cubes and calibration charts of a hammer for determining the rebound number on the field work. The hammer will be used as per manufacturer’s guidelines at various locations chosen at random. The number of location/reading on each wall, beam or column etc. shall not be less than 12. All the readings should be within the +25% range of values prescribed in calibration chart normally. However, reading indicating good strength will be when it is at per with calibrated value or between 100% & 125% and very good if more than 125% any value between 100% & 75% of calibrated value shall be considered satisfactory. Values from 75% to 50% shall be considered for payment at rates reduced on prorate basis. The concrete indicating rebound number less than 50% of calibrated value shall be rejected and not paid for.

(E) Acceptance of Field Tests and Strength If the relative strength of actual field work is found satisfactory considering the calibration charts with reference to the standard cube test kept at site, the representative work will be considered satisfactory. If the work is considered below satisfactory, the same will be dealt as stated in para D-3 above. (F) 7 days’ Strength in Rare Cases only Normally cube crushing strength on 28 days’ test shall form the basis of acceptance. However in rare cases of time bound projects/ urgent repairs 7 days’ cube test strength criteria may be adopted on similar lines using 7 days’ standard test cubes and calibration graphs/ curves/ charts for 7 days’ in lieu of 28 days’ and testing work done at 7 days’. (G) Precautions (G-1) The testing shall be done generally as per guidelines of manufacture of the apparatus and strictly in accordance with the procedure laid down in clause 6 of IS 13311 (Part 2): Indian Standard for Non-Destructive Testing of Concrete - Method of Test by Rebound Hammer. (G-2) The rebound hammers are influenced by number of factor like type of cement aggregate, surface conditions, moisture content, age of concrete & extent of calibration of concrete etc. hence care shall be taken to compare the cement, aggregate etc. and tested under the similar surface conditions having more or less same moisture content and age. However effect of age can be ignored for concrete between 3 days & 3 months old. 5.4.11 Measurements 5.4.11.1 Dimensions shall be measured nearest to a cm except for the thickness of slab which shall be measured correct to 0.5 cm. The areas shall be worked out nearest to 0.01 Sq. mt. The cubical contents shall be worked out to nearest 0.01 cubic metre. 5.4.11.2 Reinforced cement concrete whether cast-in-situ or pre cast shall be classified and measured separately as follows. CPWD SPECIFICATIONS 2009

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(a) Raft, footing, bases of columns and mass concrete etc. all work up to plinth level, column up to plinth level, plinth beams. (b) Wall (any thickness) including attached pilasters, buttresses plinth and string course, fillets, column, pillars, piers, abutments, post and struts etc. (c) Suspended floors, roofs, landings and balconies. (d) Shelves (e) Chajjas (f) Lintel, beams and bressummers. (g) Columns, pillars, piers, abutments, posts and struts. (h) Stair-cases including waist or waist less slab but excluding landing except in (i) below. (i) Spiral stair-case (including landing). (j) Arches, arch ribs, domes and vaults. (k) Chimneys and shafts. (l) Well steining. (m) Vertical and horizontal fins individually or forming box, louvers and facias. (n) Kerbs, steps and the like. (o) String courses, bands, coping, bed plates, anchor blocks, plain window sills and the like. (p) Mouldings as in cornices, window sills etc. (q) Shell, dome and folded plates. (r) Extra for shuttering in circular work in plan. 5.4.11.3 Work under the following categories shall be measured separately. (a) Rafts, footings, bases of columns etc. and mass concrete. (b) All other items upto floor two level. (c) From floor two level to floor three level and so on. (d) R.C.C. above roof level shall be measured along with R.C.C. Work in floor just below. 5.4.11.4 No deduction shall be made for the following: (a) Ends of dis-similar materials (e.g. Joists, beams, post, griders, rafter, purlins, trusses, corbels steps etc.) upto 500 sq cm in cross-section. (b) Opening upto 0.1. sqm. Note: In calculating area of openings upto 0.1 sqm the size of opening shall include the thickness of any separate lintels or sills. No extra labour for forming such openings or voids shall be paid for. (c) The volume occupied by reinforcement. (d) The volume occupied by water pipes, conduits etc. not exceeding 25 sq cm each in cross sectional area. Nothing extra shall be paid for leaving and finishing such cavities and holes. 5.4.11.5 Measurement shall be taken before any rendering is done in concrete members. Measurement will not include rendering. The measurement of R.C.C. work between various units shall be regulated as below: 143

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(a) Slabs shall be taken as running continuously through except when slab is monolithic with the beam. In that case it will be from the face to face of the beam. (b) Beams shall be measured from face to face of columns and shall be including haunches, if any, between columns and beam. The depth of the beam shall be from the bottom of slab to the bottom of beam if beam and slab are not monolithic. In case of monolithic construction where slabs are integrally connected with beam, the depth of beam shall be from the top of the slab to the bottom of beam. (c) The columns measurements shall be taken through. (d) Chajjas along with its bearing on wall shall be measured in cubic metre nearest to two places of decimal. When chajjas is combined with lintel, slab or beam, the projecting portion shall be measured as chajjas, built in bearing shall be measured as per item of lintel, slab or beam in which chajja bears. (e) Where the band and lintels are of the same height and the band serves as lintel the portion of the band to be measured as lintel shall be for clear length of opening plus twice the over all depth of band. 5.4.12 Tolerances Subject to the condition that structural safety is not impaired and architectural concept does not hamper, the tolerances in dimensions of R.C.C. members shall be as specified in the drawings by the designer. Whenever these are not specified, the permissible tolerance shall be decided by the Engineerin-Charge after consultations with the Designer, if necessary. When tolerances in dimensions are permitted, following procedure for measurement shall apply. (a) If the actual dimension of R.C.C. members do not exceed or decrease the design dimensions of the members plus or minus tolerance limit specified above, the design dimensions shall be taken for the purpose of measurement. (b) If the actual dimensions exceed the design dimensions by more than the tolerance limit, the design dimensions only shall be measured for the purpose of payment. (c) If the actual dimensions decrease more than the tolerance limit specified, the actual dimensions of the RCC members shall be taken for the purpose of measurement and payment. (d) For acceptance of RCC members whose dimensions are not exactly as per design dimensions, the decision of Engineer-in-Charge shall be final. For the purpose of payment, however, the clarification as given in para a, b & c above shall apply. 5.4.13 Rate 5.4.13.1 The rate included the cost of materials and labour involved in all the operations described above except for the cost of centring and shuttering. 5.4.13.2 On the basis of mandatory lab tests, in case of actual average compressive strength being less than specified strength but upto 70% of specified strength, the rate payable shall be in the same proportion as actual average compressive strength bears to specified compressive strength. Example: 1. Average compressive strength in 80% of specified strength. Rate payable shall be 80% of agreement rate. CPWD SPECIFICATIONS 2009

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2. In case average compressive strength is less than 70% of the specified strength, the work represented by the sample shall be rejected. 3. However, on the basis of mandatory field tests, where they prevail, the rates of the work represented by samples showing actual compressive strength less than specified strength shall be worked out as per para 5.4.10.5 (D-3) above. In addition, Engineer-in-charge may order for additional tests (see Appendix ‘B’ of chapter 5) to be carried out at the cost of contractor to ascertain if the portion of structure where in concrete represented by the samples had been used, can be retained on the basis of these tests. Engineer-in-Charge may take further remedial measured as necessary to retain the structure at the risk and cost of the contractor. 5.4.13.3 Where throating or plaster drip or moulding is not required to be provided in RCC chajjas, deduction for not providing throating or plaster drip or moulding shall be made from the item of R.C.C. in chajjas. The measurement for deduction item shall be made in running metres correct to a cm of the edge of chajja. 5.4.13.4 No extra payment for richer mix which projects into any member from another member during concreting of junctions of beams and columns etc. will be made except to the extent structurally considered necessary and when so indicated in the structural drawings. The payment for work done under items of different mixed shall be limited strictly to what is indicated in the structural drawings. 5.5 ENCASING ROLLED STEEL SECTIONS 5.5.1 General Requirements Before concrete work is started, the Engineer-in-Charge shall check that all rolled steel sections to be encased, have been erected truly in position. The sections shall be unpainted and shall be wire brushed to remove the loose rust/ scales etc. Where so specified, ungalvanised metal, having mesh or perforations large enough to permit the free passage of 12.5 mm nominal size aggregate through them shall be wrapped round the section to be encased and paid for separately. 5.5.2

Wrapping

5.5.2.1 In case of columns, the wrapping shall be arranged as illustrated in Fig. 5.27 to pass through the centre of the concrete covering. The wrapping of the entire length of the columns be carried out in stages and no stage shall cover more than 1.5 metre of height of columns. Successive wrappings shall be carried out only after the immediate adjacent wrapping has been encased in concrete. The surface and edges of the flanges of the steel columns shall have a concrete cover of not less than 50mm. The wrappings of the successive stages shall be tied together. 5.5.2.2 In the case of beams and grillages, the wire mesh or expanded metal shall be wrapped round the lower flange of the beam as illustrated in Fig. 5.28 and the wrapping shall be suspended by wire hangers 5 mm diameter placed at about 1.2 metres centres. The surfaces and edges of the steel sections shall have a concrete cover of not less than 50mm. The wrapping shall pass through the centre of the concrete covering at the edges and soffits of the flanges. 5.5.3 Form Work shall be as prescribed in 5.2. 5.5.4 Concreting Concrete shall consist of a mix of 1:2:4 (1 cement : 2 coarse and : 4 graded stone aggregate of 12.5 mm nominal size) unless a richer mix is specified. The mix shall be poured solidly around the steel sections and around the wrapping by vibrating the concrete into position. Consistency of concrete, Placing of concrete and its compaction, curing, finishing and strength of concrete shall be as described in 5.4. 145

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5.5.5 Measurements The length shall be measured correct to one cm and other dimensions correct of 0.5 cm. The cement concrete shall be measured as per gross dimensions of the encasing exclusive of the thickness of plaster. No deduction shall be made for the volume of steel sections, expanded metal, mesh or any other reinforcement used therein. However, in case of boxed stanchions or girders, the boxed portion only shall be deducted. Fabric reinforcement such as expanded metal shall be measured separately in square metres stating the mesh and size of strands. The description shall include the bending of the fabric as necessary, Racking or circular cutting and waste shall be included in the description. 5.5.6 Rate The rate shall include the cost of materials and labour required for all the operations described above except the cost of fabric reinforcement. The cost of providing and erecting steel section and wire hangers shall be paid for separately. 5.6 PRECAST REINFORCED CONCRETE 5.6.1 General Requirements Precast reinforced concrete units such as columns, fencing posts, door and window frames, lintels, chajjas, copings, sills , shelves, slabs, louvers etc. shall be of grade of mix as specified and cast in forms or moulds. The forms/ moulds shall be of fiber glass or of steel sections for better finish. Provision shall be made in the forms and moulds to accommodate fixing devices such as nibs, clips, hooks, bolts and forming of notches and holes. The contractor may precast the units on cement or steel platform which shall be adequately oiled provided the surface finish is of the same standard as obtained in form. Each unit shall be cast in one operation. 5.6.2 Concrete used for precasting the units should be well proportioned, mixed, placed and thoroughly compacted by vibrations or tamping to give a dense concrete free from voids and honey combing. 5.6.3 Precast articles shall have a dense surface finish showing no coarse aggregate and shall have not cracks or crevices likely to assist in disintegration of concrete or rusting of steel or other defects that would interfere with the proper placing of the units. All angle of the precast units with the exception of the angles resulting from the splayed or chamfered faces shall be true right angles. The arises shall be clean and sharp except those specified or shown to be rounded. The wearing surface shall be true to the lines. On being fractured, the interior of the units should present a clean homogeneous appearance. 5.6.4 The longitudinal reinforcement shall have a minimum cover of 12 mm or twice the diameter of the main bar, whichever is more, unless otherwise directed in respect of all items except fencing posts or electric posts where the minimum cover shall be 25 mm. 5.6.5 Curing After having been cast in the mould or form the concrete shall be adequately protected during setting in the first stages of hardening from shocks and from harmful effects of frost, sunshine, drying winds and cold. The concrete shall be cured at least for 7 days from the date of casting. 5.6.6 The precast articles shall be matured for 28 days before erection or being built in so that the concrete shall have sufficient strength to prevent damage to units when first handled. 5.6.7 Marking Precast units shall be clearly marked to indicate the top of member and its location and orientation in the structure.

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5.6.8 Precast units shall be stored, transported and placed in position in such as manner that they will not be overstressed or damaged. 5.7 PRECAST CEMENT CONCRETE JALI 5.7.0 The jali shall be of cement concrete 1:2:4 (1 cement 2 coarse sand:4 stone aggregate 6 mm nominal size) reinforced with 1.6 mm thick mild steel wire, unless otherwise specified. 5.7.1 Fixing The jali shall be set in position true to plumb and level before the joints sills and soffits of the openings are plastered. It shall then be properly grouted with cement mortar 1:3 (1 cement :3 coarse sand) and rechecked for levels. Finally the jambs, sills and soffits shall be plastered embedding the jali uniformly on all sides. 5.7.2 Measurements The jali shall be measured for its gross superficial area. The length and breadth shall be measured correct to a cm. The thickness shall not be less than that specified. 5.7.3 Rate The rate shall be inclusive of materials and labour involved in all the operations described above except plastering of jambs, sills and soffits, which will be paid for under relevant items of plastering. 5.8 DESIGN MIX 5.8.0 Definition Design mix concrete is that concrete in which the design of mix i.e. the determination of proportions of cement, aggregate & water is arrived as to have target mean strength for specified grade of concrete. The minimum mix of M25 shall be used in all structural elements in both load bearing & RCC framed construction. 5.8.1 Mix Design and Proportioning 5.8.1.1 Mix proportions shall be designed to ensure that the workability of fresh concrete is suitable for conditions of handling and placing, so that after compaction it surrounds all reinforcement and completely fills the formwork. When concrete is hardened, it shall have the stipulated strength, durability and impermeability. 5.8.1.2 Determination of the proportions by weight of cement, aggregates and water shall be based on design of the mix. 5.8.1.3 As a trial the manufacturer of concrete may prepare a preliminary mix according to provisions of SP: 23. Reference may also be made to ACI 211.1-77 for guidance. 5.8.1.4 Mix design shall be tried and the mix proportions checked on the basis of tests conducted at a recognized laboratory approved by the Engineer-in-Charge. 5.8.1.5 All concrete proportions for various grades of concrete shall be designed separately and the mix proportions established keeping in view the workability for various structural elements, methods of placing and compacting. 5.8.1.6 Before using an admixture in concrete, its performance shall be evaluated by comparing the properties of concrete with the admixture and concrete without any admixture. Chloride content of admixture should be declared by the manufacturer of admixture and shall be within limits stipulated by IS:9103. 5.8.2 Standard Deviation 5.8.2.1 Standard deviation calculations of test results based on tests conducted on the same mix design for a particular grade designation shall be done in accordance with IS 456. 147

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5.8.3 Acceptance Criteria 5.8.3.1 Compressive Strength : The concrete shall be deemed to comply with the strength requirements when both the following condition are met: (a) The mean strength determined from any group of four consecutive test results complies with the appropriate limits in col 2 of Table 5.6. (b) Any individual test result complies with the appropriate limits in col. 3 of Table 5.6. 5.8.3.2 Flexural Strength : When both the following conditions are met, the concrete complies with the specified flexural strength. (a) The mean strength determined from any group of four consecutive test results exceeds the specified characteristic strength by at least 0.3 N/mm2. (b) The strength determined from any test result is not less than the specified characteristic strength/ 0.3 N/mm2. 5.8.3.3 Quantity of Concrete Represented by Strength Test Results : The quantity of concrete represented by a group of four consecutive test results shall include the batches from which the first and last samples were taken together with all intervening batches. For the individual test result requirements given in col 3 of Table 5.6 or in item (b) of 5.8.3.2. Only the particular batch from which the sample was taken shall be at risk. Where the mean rate of sampling is not specified the maximum quantity of concrete that four consecutive test results represent shall be limited to 60 m3. 5.8.3.4 If the concrete is deemed not to comply pursuant to 5.8.3 the structural adequacy of the parts affected shall be investigated and any consequential action as needed shall be taken. 5.8.3.5 Concrete of each grade shall be assessed separately. 5.8.3.6 Concrete is liable to be rejected if it is porous or honey-combed, its placing has been interrupted without providing a proper construction joint, the reinforcement has been displaced beyond the tolerances specified, or construction tolerances have not been met. However, the hardened concrete may be accepted after carrying out suitable remedial measured to the satisfaction of the Engineer-inCharge. 5.8.4 Cement Content of Concrete 5.8.4.1 For all grades of concrete manufactured/produced, minimum cement content in the concrete shall be 330 kg per cubic metre of concrete. Also, irrespective of the grade of concrete the maximum cement content shall not be more than 500 kg per cubic metre of concrete. These limitations shall apply for all types of cements of all strengths. 5.8.4.2 Actual cement content in each grade of concrete for various conditions of variable shall be established by design mixes within the limits specified in para 5.8.4.1 above. 5.8.5 Water Cement Ratio and Slump 5.8.5.1 In proportioning a particular mix, the manufacturer/ producer/ contractor shall give due consideration to the moisture content in the aggregates, and the mix shall be so designed as to restrict the maximum free water cement ratio to less than 0.5. 5.8.5.2 Due consideration shall be given to the workability of the concrete thus produced. Slump shall be controlled on the basis of placement in different situations. For normal methods of placing concrete, maximum slump shall be restricted to 100 mm when measured in accordance with IS 1199. CPWD SPECIFICATIONS 2009

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TABLE 5.6 Characteristic Compressive Strength Compliance Requirement (Clause 5.8.3.1 and 5.8.3.3) Mean of the Group of 4 Non- Individual Test Results in N/mm3 Overlapping Consecutive Test Results in N/mm3 (1) (2) (3) ≥ fck-3 N/mm2 M15 ≥ fck + 0.825 x established standard deviation (rounded off to nearest 0.5 N/mm2) or fck +3 N/mm2 Whichever is greater ≥ fck-4 N/mm2 M20 ≥ fck + 0.825 x established standard or deviation (rounded off to nearest 0.5 above N/mm2) or fck +4 N/mm2, Whichever is greater NOTE – In the absence of established value of standard deviation, the values given in Table may be assumed, and attempt should be made to obtain results of 30 samples as early as possible to establish the value of standard deviation.

Specified Grade

5.8.6 Approval of Design Mix 5.8.6.1 The producer/ manufacturer/ contractor of concrete shall submit details of each trial mix of each grade of concrete designed for various workability conditions to the Engineer-in-Charge for his comments and approval. Concrete of any particular design mix and grade shall be produced/ manufactured for works only on obtaining written approval of the Engineer-in-Charge. 5.8.6.2 For any change in quality/ quantity in the ingredients of a particular concrete, for which mix has been designed earlier and approved by the Engineer-in-Charge, the mix has to be redesigned and approval obtained again. 5.9 READY MIXED CONCRETE (as per IS 4926) 5.9.1 Materials 5.9.1.1 Selection and Approval of Materials : Materials used should satisfy the requirements for the safety, structural performance durability and appearance of the finished structure, taking full account of the environment to which it will be subjected. The selection and use of materials shall be in accordance with IS 456. Materials used shall conform to the relevant Indian Standards applicable. Where materials are used which are not covered by the provisions of the relevant Indian Standard, there should be satisfactory data on their suitability and assurance of quality control. Records and details of performance of such materials should be maintained. Account should be taken of possible interactions and compatibility between IS 4926 and materials used. Also, prior permission of the purchaser shall be obtained before use of such materials. 5.9.1.2 Cement : Cement used for concrete shall be in accordance with the requirements of IS 456. . 5.9.1.3 Mineral Admixtures : Use of mineral admixtures shall be permitted in accordance with the provisions of IS 456.

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5.9.1.4 Aggregates : Aggregates used for concrete shall be in accordance with the requirement of IS 456. Unless otherwise agreed testing frequencies for aggregates in plant shall be as given IS 4926. 5.9.1.5 Chemical Admixtures (i) Use of chemical admixtures shall be permitted in accordance, with the provisions of IS 456 and IS 9103. (ii) It shall be the responsibility of the producer to establish compatibility and suitability of any admixture with the other ingredients of the mix and the determine the dosage required to give the desired effect. (iii) Admixtures should be stored in a manner that prevents degradation of the product and consumed within the time period indicated by the admixture supplier. Any vessel containing an admixture in the plant or taken to site by the producer shall be clearly marked as to its content. (iv) When offering or delivering a mix to a purchaser it should be indicated if such a mix contains an admixture or combination of admixtures or not. The admixtures may be identified generically and should be declared on the delivery ticket. (v) The amount of admixture added to mix shall be recorded in the production record. In special circumstances, if necessary, additional dose of admixture may be added at project site to regain the workability of concrete with the mutual agreement between the producer and the purchaser. 5.9.1.6 Water : Water used shall be in accordance with the requirement of IS 456. Unless otherwise agreed, the testing frequencies for water shall be as given in Annex A. The use of re-cycled water is encouraged as long as concrete of satisfactory performance can be produced and steps are taken to monitor the build up of chlorides in any recirculated water and that any subsequent adjustments to the mix design are made to ensure that any overall limit on chloride contents is satisfied. The addition of any recycled water shall be monitored and controlled to meet these requirements. The total amount of water added to the mix shall be recorded in the production record. The water content of concrete shall be regulated by controlling its workability or by measuring and adjusting the moisture contents of its constituent materials. The producer’s production staff and truck-mixer, drivers shall be made aware of the appropriate responses to variations in concrete consistency of a particular mix caused by normal variations in aggregate moisture content or grading. 5.9.2 General Requirements 5.9.2.1 Basis of Supply : Ready-mixed concrete shall be supplied having the quality and the quantity in accordance with the requirement agreed with the purchaser or his agent. Notwithstanding this, the concrete supplied shall generally comply with requirements of IS 456. All concrete will be supplied and invoiced in terms of cubic metres (full or part) of compacted fresh concrete. All proportioning is to be carried out by mass except water and admixture, which may be measured by volume. 5.9.2.2 Transport of Concrete : Ready-mixed concrete shall be transported from the mixer to the point of placing as rapidly as practicable by methods that will maintain the required workability and will prevent segregation, loss of any constituents or ingress of foreign matter or water. The concrete shall be placed as soon as possible after delivery, as close as is practicable to its final position to avoid re-handling or moving the concrete horizontally by vibration. If required by the purchaser the producer can utilize CPWD SPECIFICATIONS 2009

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admixtures to slow down the rate of workability loss, however this does not remove the need for the purchaser to place the concrete as rapidly as possible. The purchaser should plan his arrangements so as to enable a full load of concrete to be discharged within 30 minutes of arrival on site. Concrete shall be transported in a truck-mixer unless the purchaser agrees to the use of nonagitating vehicles. When non-agitating vehicles are used, the mixed concrete shall be protected from gain or loss of water. 5.9.2.3 Time in Transport : The general requirement is that concrete shall be discharged from the truck-mixer within 2 h of the time of loading. However, a longer period may be permitted if retarding admixtures are used or in cool humid weather or when chilled concrete is produced. The time of loading shall start from adding the mixing water to the dry mix of cement and aggregate or of adding the cement to the wet aggregate whichever is applicable. Ready-mixed concrete plant shall have test facilities at its premises to carry out routine tests as per the requirement of the standard. 5.9.3 Sampling and Testing of Ready-Mixed Concrete 5.9.3.1 Point and Time of Sampling : For the assessment of compliance of ready-mixed concrete, the point and time of sampling shall be at discharge from the producer’s delivery vehicle or from the mixer to the site or when delivered into the purchaser’s vehicle. It is critical that the sampling procedure and equipment used enables as representative a sample as possible to be taken of the quantity of concrete delivered (see Annex A). The sampling may be carried out jointly by the purchaser and the supplier with its frequency mutually agreed upon. However, it will not absolve the supplier of his responsibility from supplying in concrete as per the requirement given in this standard or otherwise agreed to where so permitted in the standard. 5.9.3.2 Workability : The test for acceptance is to be performed upon the producer’s delivery vehicle discharge on site or upon discharge into the purchaser’s vehicle. lf discharge from the producers’ vehicle is delayed on site due to lack of preparedness on behalf of the purchaser then the responsibility passes to the purchaser after a delay of more than 30 min. The workability shall be within the following limits on the specified value as appropriate: Slump ± 25 mm or 1/3 of the specified value, whichever is less. Compacting factor : ± 0.03, where the specified value is 0.90 or greater, ± 0.04, where the specified value is less than 0.90 but more than 0.80, ± 0.05, where the specified value is 0.80 or less. Flow table test may be specified for concrete, for very high workability (see IS 9103) Acceptance criteria for spread (flow) are to be established between the supplier and the purchaser. 5.9.3.3 Specified Strength (i) Compliance shall be assessed against the requirements of IS 456 or other agreed Indian Standard. The purchaser may perform his sampling and testing or may enter into an arrangement with the producer to provide his testing requirements. (ii) Unless otherwise agreed between the parties involved, the minimum testing frequency to be applied by the producer in the absence of a recognized ready- mixed concrete industry method of production control should be one sample for every 50 m3 of production or every 50 batches, whichever is the greater frequency. Three test specimens shall be made up for each sample for testing at 28 days (see also IS 456). 151

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In order to get a relatively quicker idea of the quality of concrete, optional test on beams for modulus of rupture at 72 ± 2 h or at 7 days or compressive strength test at 7 days may be carried out in addition to 28 days compressive strength test. For this purpose the value should be arrived at based on actual testing. In all cases 28 days compressive strength shall alone be the criteria for acceptance or rejection of the concrete. (iii) The purchaser shall inform the producer if his requirements for sampling and testing are higher than one sample every 50 m3 or 50 batches, whichever is the greater frequency. 5.9.3.4 Additional Compliance Criteria : Any additional compliance criteria shall be declared to the producer by the purchaser prior to supply and shall be mutually agreed upon in terms of definition, tolerance frequency of assessment, method of test and significance result. 5.9.3.5 Non-Compliance : The action to be taken in case of non-compliance shall be declared and mutually agreed upon. 5.9.4 Information to be Supplied by the Purchaser 5.9.4.1 The purchaser shall provide to the producer the details of the concrete mix or mixes required by him and all pertinent information on the use of the concrete and the specified requirements. Prior to supply taking place, it is recommended that a meeting is held between the purchaser and the producer. Its objective to clarify operational matters such as notice to be given prior to delivery, delivery rate, the name of the purchasers authorized representative who will coordinate deliveries, any requirements for additional services such as pumping, on site testing or training, etc. 5.9.4.2 Designed Mixes : Where the purchaser specifies a designed mix to be supplied it is essential that all relevant information is conveyed to the producer. In order to assist in this, the format given in Annex B may be completed and forwarded to the producer at the time of enquiry. 5.9.4.3 Prescribed Mixes : The concrete mix shall be specified by its constituent materials and the properties or quantities of those constituents to produce a concrete with the required performance. The assessment of the mix proportions shall form an essential part of the compliance requirements. The purchaser shall provide the producer with all pertinent information on the use of the concrete and the specified requirements. In order to assist in this, the format given in Annex B may be followed with suitable modifications as applicable to prescribed mixes. 5.9.5 Information to be Supplied by the Producer When requested, the producer shall provide the purchaser with the following information before any concretes is supplied: (a) Nature and source of each constituent material, (b) Source of supply of cement, (c) Proposed proportions or quantity of each constituent/ m3 of fresh concrete. (d) Generic type(s) of the main active constituent(s) in the admixture; (e) Whether or not the admixture contains chlorides and if so, the chloride content of the admixture expressed as a percentage of chloride ion by mass of admixture; (f) Where more than one admixture is used, confirmation of their compatibility and (g) Initial and final setting time of concrete when admixture is used at adopted dosage (tested as per IS 8142).

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5.9.6 Production and Delivery 5.9.6.1 Materials Storage and Handling (i) Cement : Separate storage for Different types and grades of cement shall be provided. Containers may be used to store cement of different types provided these are emptied before loading new cement. Bins or silos shall be weatherproof and permit free flow and efficient discharge of the cement. Each silo or compartment of a silo shall be completely separate and fitted with a filter or alternative method of dust control. Each filter or dust control system shall be of sufficient size to allow delivery of cement to be maintained at a specified pressure, and shall be properly maintained and prevent undue emission of cement dust and prevent interference with weighing accuracy by build up of pressure. Cement shall be stored and stacked in bags and shall be kept free from the possibility of any dampness or moisture coming in contact with them and where cement can be stored and retrieved without undue damage to the bags. The bags are to be protected from becoming damp either from the ground or the weather. The cement is to be used in the order it is delivered (see also IS 4082). In case, the cement remains in storage for more than 3 months, the cement shall be retested before use and shall be rejected, if it fails to conform to any of the requirements given in the relevant Indian Standard. (ii) Dry Pulverized Fuel Ash and Other Mineral Admixtures : Suitable separate arrangement for storage of pulverized fuel ash, silica fume, metakeolin, rice husk ash, ground granulated blast furnace slag such as for cement, shall be provided, in the plants utilizing these materials. (iii) Aggregates (Coarse and Fine) : Stockpiles shall be free draining and arranged to avoid contamination and to prevent intermingling with adjustment material. Handling procedures for loading and unloading aggregates shall be such as to reduce segregation to a minimum. Provision shall be made for separate storage for each nominal size and type of aggregate and the method of loading of storage bins shall be such as to prevent intermingling of different sizes and types. Fine aggregates shall be stacked in a place where loss due to the effect of wind is minimum (see also IS 4082 and IS 456). (iv) Water : An adequate supply shall be provided and when stored on the plant such storage facilities shall be designed to minimize the risk of contamination. (v) Chemical Admixtures : Tanks or drums containing liquid admixtures shall be clearly labeled for identification purposes and stored in such a way to avoid damage, contamination or the effects of prolonged exposure to sunlight (if applicable). Agitation shall be provided for liquid admixture, which are not stable solutions. 5.9.6.2 Batching Plants and Batching Equipment : Hoppers for weighing cement, mineral admixtures, aggregates and water and chemical admixture (if measured by mass) shall consist of suitable container freely suspended from a scale or other suitable load-measuring device and equipped with a suitable discharging mechanism. The method of control of the loading mechanism shall be such that, as the quantity required in the weighing hopper is approached the material may be added at controllable rate and shut off precisely within the weighing tolerances specified in Annex C. The weighing hoppers for cement, mineral admixtures aggregate shall be capable of receiving their rated load, without the weighed material coming into contact with the loading mechanism. Where the rated capacity of a batching plant mixing cycle is less than 2.0 m3, additional precautions shall be taken to ensure that the correct number of batches are loaded into the truck mixer. The weighing hoppers shall be constructed so as to discharge efficiently and prevent the build up of materials. A tare adjustment, up to 10 percent of the nominal capacity of the weigh scale, shall be provided on the weighing mechanism so that the scale can be adjusted to zero at least once each day. Dust seals shall be provided on cement hoppers between the loading mechanism and the weigh hopper, and shall be fitted so as to prevent the emission of cement dust and not affect weighing accuracy. The hopper shall be vented to permit escape of air without emission of cement dust. 153

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Vibrator or other attachment, where fitted, shall not affect the accuracy of weighing. There shall be sufficient protection to cement and aggregate weigh hoppers and weighing mechanisms to prevent interference with weighing accuracy by weather conditions or external build-up of materials. Where chemical admixture dispensers are used, they shall be capable of measurement within the tolerance in annex C and calibrated container or weigh scales shall be provided to check the accuracy of measurement at least once a month. Where a continuous mixer with ribbon loading is used the batching procedure specified by the manufacture of the plant shall be followed. Each control on the batching console and weigh-dial or display shall be clearly labeled with its function and where concerned with the batching of materials, the materials type. When more than one type or grade of cement is being used, the weighing device and discharge screw or other parts of the transfer system shall be empty before changing from on type of cement to another. When more than one type or grade of cement is being used, the weighing devised and discharge screw or other parts of the transfer system shall be empty before changing from on type of cement to another. When pulverized fuel ash and other mineral admixtures are batched through the cement weigh system, the weighing device and discharge screw or other parts of the transfer system shall be empty when the weighing system has returned to zero reading or completed the batch. Where a back weigh system is utilized to weigh materials a system shall be in place so as to prevent materials being loaded during the process of weighing. 5.9.6.3 Measurement of Materials : Cement and mineral admixture materials shall be measured by mass in a hopper or compartment separate from those used for other materials and on a scale of appropriate sensitivity, measurement being taken from a zero reading. Aggregates shall be measured by mass, allowance being made for the free moisture content of the aggregates. The added water shall be measured by volume or by mass. Any liquid chemical admixture (or paste) shall be measured by volume or by mass and any solid admixture by mass. When weighing materials any build up in the hopper during the day must be tared out or allowed for in the batch weights. After measurement all materials shall be discharged into the mixer without loss. The accuracy of the measuring equipment shall be within + 2 percent of the quantity of cement and mineral admixtures being measured and within + 3 percent of the quantity of aggregate, chemical admixture and water being measured. The plant operator shall be provided with a clear display of the quantities of materials to be batched for each mix and batch size with information identifying the display to be selected for each designed and prescribed mix to be produced. Analogue scale displays for the weighing of cement, mineral admixtures, aggregates and water shall be readily discernable from the operating position. For digital readouts the numerals shall be readily discernable from the operating position . Fully automatic production systems shall be fitted with control equipment to allow the correct operation of the plant to be monitored during weighing and batching. Automatic control systems on batching plants shall not commence batching until all hoppers have been emptied and /or tared and the scales zeroed unless such systems are designed to take account of build up in their programming. All scales shall be tested and calibrated as per Annex C. CPWD SPECIFICATIONS 2009

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5.9.6.4 Mixing (i) Washing Out Water : Before loading concrete materials or mixed concrete into either a stationary mixer or truck mixer any water retained in the mixing drum for washing out purposes shall be completely discharged. (ii) Stationary or Central Mixers : Stationary mixers shall not be loaded in excess of the manufacturer’s rated capacity. The mixing time shall be measured from the time all the materials required for the batch, including water, are in the drum of the mixer. The mixing time shall not be less than that recommended by the manufacturer. Where a continuous mixing plant is used, the complete mixing time shall be sufficient to ensure that the concrete is of the required uniformity. (iii) Truck Mixers : When a truck mixer is used for the partial or complete mixing of concrete, mixing shall be considered to commence from the moment when all the materials required for the batch, including water, are in the rotating drum of the mixer. Truck or agitators shall not be loaded in excess of the manufacturer’s rated capacity. In order to produce a satisfactory mix, and where there is no data available to establish different period and speed of revolutions, mixing shall continue for not less than 60 revolutions of the truck mixer drum at a rate of not less than 7 revolutions/min. All completely truck mixed concrete shall be visually inspected for uniformity prior to leaving the plant. When a truck mixer or agitator is used for transporting concrete which has been mixed before leaving the plant, the concrete shall be agitated during transit and remixed at the site for at least 2 min so that the concrete is of the required uniformity. Where water is added to the concrete in the truck mixer through the truck mixer water meter and when such water is being accounted for in the total water within the mix, it shall be ensured that the truck mixer water meter is in operational condition and properly calibrated. Where a water meter is not available, water must be measured in a suitable container before being added to the truck mixer. (iv) Condition of Mixers : Stationary and truck mixers shall be maintained in an efficient and clean condition with no appreciable build up of hardened concrete or cement in the mixing drum, on the mixing blades, or on the loading hopper or discharge chutes. 5.9.6.5 Delivery Ticket : Immediately before discharging the concrete at the point of delivery, the producer or his representative shall provide the purchaser with a preprinted delivery ticket for each delivery of concrete on which is printed, stamped or written the minimum information detailed invoicing as per Annex D. 5.9.7 Quality Control Quality control of ready-mixed concrete may be divided into three components, forward control, immediate control and retrospective control. 5.9.7.1 Forward control : Forward control and consequent corrective action are essential aspects of quality control. Forward control includes the following. (i) Control of purchased material Quality (ii) Control of Materials storage (iii) Mix design and mix design modification 155

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(iv) Transfer and Weighing Equipment : The producer shall be able to demonstrate that a documented calibration procedure is in place. The use of elector-mechanical weighing and metering systems, that is, load cells, flow meters, magmeters, etc, is preferable over purely mechanical system, that is, knife edge and lever systems. (v) Plant mixers where present and truck mixers used shall be in an operational condition. 5.9.7.2 Immediate Control : Immediate control is concerned with instant action to control the quality of the concrete being produced or that of deliveries closely following. It includes the production control and product control. (i) Production Control : The production of concrete at each plant shall be systematically controlled. This is to ensure that all the concrete supplied shall be in accordance with these requirements and with the specifications that has formed the basis of the agreement between the producer and purchaser. Each load of mixed concrete shall be inspected before dispatch and prior to discharge. The workability of the concrete shall be controlled on a continuous basis during production and any corrective action necessary taken. For each load, written, printed or graphical records shall be made of the mass of the materials batched, the estimated slump, the total amount of water added to the load, the delivery ticket number for that load, and the time the concrete was loaded into the truck. Regular routine inspections shall be carried out on the condition of plant and equipment including delivery vehicles. (ii) Product Control : Concrete mixes shall be randomly sampled and tested for workability and where appropriate, plastic density, temperature and air content. Where significant variations from target values are detected, corrective action shall be taken. It is important to maintain the water cement ratio constant at its correct value. The amount of added water shall be adjusted to compensate for any observed variations in the moisture contents in the aggregates. Suitable adjustments should also be made in masses of the aggregates due to this variation (see IS 456). Any change in water content due to change in aggregate grading shall be taken care of by forward control by suitable modifications to mix design. 5.9.7.3 Retrospective Control : Retrospective control is concerned with those factors that influence the control of production. Retrospective control may cover any property of materials or concrete, such as aggregate grading, slump, or air content, but is particularly associated with 28-day cube strength because by its very nature it is not property which can be measured ahead of, or at the time of, manufacture. 5.9.7.4 Mix Performance : The producer shall be responsible for ensuring that suitable control procedures are in place ensure the following. (i) Design Mixes : A quality control system shall be operated to control the strength of design mixes to the levels required as per IS 456 and shall be based on random tests of mixes which form the major proportion of production. The system shall include continuous analysis of results from cube tests to compare actual with target values together with procedures for modifying mix proportions to correct for observed differences. Compressive strength testing shall be carried out using a machine that meets the requirements of IS 14858.

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(ii) Prescribed Mixes : Periodic and systematic checks shall be made to ensure that the cementitious material contents of prescribed mixes comply with their mix descriptions. 5.9.7.5 Stock Control of Materials : The producer shall operate a materials stock control procedure to enable verification of total quantities used and to confirm that only approved materials have been received. 5.9.7.6 Complaints : The producer shall have a procedure in place to enable the diagnosis and correction of faults identified from complaints. 5.9.8 Order Processing A competent person to interpret the specified requirements and relate these to mix design criteria shall systematically review specification and orders supplied by the purchaser. These shall be formally recorded together with any modification to the specification resulting from subsequent agreed documentation to ensure that the plant operator is given the correct instructions for batching and mixing. When mixes or materials are offered as alternatives to requested mixes or where there is no specification supplied by the purchaser, orders whether received verbally or in writing, shall be agreed with the purchaser and the fact recorded. Alternatives to the mix description or compliance requirements in the purchaser’s specification shall be clearly identified in the quotation. 5.9.9 Records Records shall be maintained by the producer to provide confirmation of the quality and quantity and quantity of concrete produced. The records shall be retained for the purposes of these requirements for a period of at least one year. They shall cover the following aspect: (a) Production and delivery: (i) Batching instruction (ii) Batching Records, (iii) Delivery tickets, and (iv) Equipment calibration and plant maintenance. (b) Materials and production control: (i) Concrete production and materials purchase, usage and stocks, and (ii) Certificates or test results for materials. (c) Production quality Contol: Control test results. 5.10 PLACING CONCRETE BY PUMPING 5.10.1 General Concrete conveyed by pressure through either rigid pipes or flexible hoses and discharged directly into the desired area is termed as pumped concrete. Method of applying pressure to concrete is by pumps. Pumps to be used shall be either of the two types as mentioned below:(A) Piston type pumps (B) Squeeze pressure type pumps. Compressed air pressure pumps shall not be used in the works. 5.10.2 Pumping Equipments 5.10.2.1 Piston Pumps : Piston pump to be used in the works shall consist of a receiving hopper for mixed concrete, an inlet valve, an outlet valve, and the pump shall be a twin-piston pump. The two pistons shall be so arranged that one piston retracts when the other is moving forward and pushing concrete into the pipe line to maintain a reasonably steady flow of concrete. Single piston pumps shall not be acceptable. 157

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Inlet and outlet valve shall be any one of the following types:- Rotating plug type - Sliding plate type - Guided plunger type - Swing type - Flapper type - Or any combination of the above. The pistons shall be mechanically driven using a crank or chain or hydraulically driven using oil or water. The receiving hopper shall have a minimum capacity of 1.0 cum and the hopper shall be fitted with remixing rotating blades capable of maintaining consistency and uniformity of concrete. The primary power for pumps may be supplied by gasoline, diesel, or electric motors. The primary power unit and the pump unit may be truck, trailer or skid mounted. 5.10.2.2 Squeeze Pressure Pumps : Squeeze pressure pumps shall consist of a receiving hopper fitted with re-mixing blades. Re-mixing blades shall be such that these can push the concrete into the flexible hose connected at the bottom of the hopper. The flexible hose shall pass through a metal drum around the inside periphery of the drum and come out through the top part of the drum. The drum shall be maintained under a very high degree of a vacuum during operation. The drum shall be so fitted with hydraulically operation metal rollers., which when rotating, create a squeeze pressure on the flexible hose carrying concrete and forces the concrete out into the pipe line. 5.10.2.3 Effective Range and Discharge of Pumps : Effective range of pumps to be used in the work shall be decided after studying the site conditions. However, the minimum horizontal range shall not be less than 150 metres and minimum vertical range shall not be less than 50 metres. Selection of pumps bases on discharge capacity shall be decided after studying the requirements for the project. Discharge capacity shall be worked out by the contractors and approval obtained from the Engineer-in-Charge. As a guide line figure the contractor may assume a discharge capacity of 15 cubic metre/hour/pump. 5.10.2.4 Pipe Lines : All concrete carrying pipe lines shall generally be rigid pipe lines. Flexible pipe lines may only be used at bend curves in lines or at discharge ends if required. Placements of flexible units shall be done judiciously and connected to the pipe lines only when it meets the approval of the Engineer-in-Charge. (i) Rigid Line/ Hard Line/ Slick line : Such lines shall be made either of steel or plastic. Aluminum alloy pipes shall not be used. Minimum pipeline diameter shall be 100 millimeters and shall have normal maximum length of 3 metre in each section connected through couplers. (ii) Flexible Pipe Line : Flexible lines shall be made out of rubber or spiral wound flexible metal or plastic. The pipe shall again be such that they are in sections of 3 metre length each and connected through couplers. These pipes shall be such that they are interchangeable with rigid lines. While installing flexible units, care shall be taken that there are no links in the pipeline, which is a normal tendency with these pipes having diameter 100 mm and above.

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5.10.2.5 Couplers : Couplers to be used for connecting pipe line sections (either hard or flexible) shall have adequate strength to withstand stresses due to handling, misalignments, poor support to pipe lines etc. For horizontal runs of pipes and for vertical run upto 30 metre height the couplers shall be rated for a minimum pressure of 35 kg/ cm square. Couplers used for rising runs between 30 metre and 50 metre heights shall have a minimum pressure rating of 50 kg/cm square. Couplers shall be designed to allow for replacement of any pipe section without displacing other sections. These shall provide for the full internal cross section. These shall provide for the full internal cross section with no constructions or service. Which may disrupt the smooth flow of concrete. For pipelines of size 150mm and above, double togged type coupler with a thick rubber gasket and secondary wedge-take-up is recommended. Types of couplers that may be used shall be any of the following:-

Grooved end coupler

-

One piece extended lever swing type couplers

-

And full flow oil line type couplers.

5.10.2.6 Other Accessories : Other accessories which shall be catered for, are as under:(a) Back up pump of rigid and flexible pipes of varying lengths of similar rating/specifications (b) Curved sections of rigid pipes (c) Swivel joints and rotary distributors (d) Pin and gate valves to prevent back flow in pipe lines (e) Switch valves to direct the flow into another pipe line (f) Connection devices to fill forms from the bottom up (g) Splints, rollers, and other devices for protection of conduit over rock concrete Reinforcing steel and form and to provide lifting and lashing points in the pipe line. (h) Transitions for connecting different sizes of pipe sections (i) Air vents for downward pumping. (j) Clean out equipment. For concreting of columns, walls and scattered small placement, recommendation is made for special cranes or power controlled booms carrying pipe lines with a pendant type concrete delivery hose. 5.10.2.7 Lubricating of Pipe Line Before pumping concrete into the pipeline, the line shall be lubricated with a properly designed mortar/grout lubricant. This shall be ensured by starting the pumping operation with a properly designed mortar, or with a batch of regular concrete with the coarse aggregate omitted. The quantity of mortar required as lubricant is dependent on the smoothness and cleanliness of the pipelines. As a guide line, for a 100 mm diameter pipe line of 100 metre length, 0.08 cum to 0.10 cum of mortar should normally be adequate, but this shall not be taken as specified, and the contractor shall establish his requirements.

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The quantity of mortar that comes out of the delivery end of the pipeline shall not be used in place of the concrete work. However, with the approval of Engineer-in-Charge, this mortar may be used as bedding mortar against construction joints. The rest of the mortar shall be wasted. Lubrication shall be maintained as long as the pumping of concrete continues. 5.11 GUIDELINES FOR FIELD PRACTICE 5.11.1 General Precautions (i) Proper planning of concrete supply, pump locations, line layout, placing sequence and the entire pumping operation will result in savings of time and expense. (ii) The pump shall be placed as near the placement area as practicable. The surrounding area of the pump shall be free of obstructions to allow for movement of concrete delivery trucks. The surface must be strong enough to withstand the loaded trucks operating on it. If the surface is a suspended slab, the truck route shall be adequately supported in consultation with the Engineerin-Charge. (iii) Pipe lines from the pump to the placing area shall be laid with minimum number of bend. For large placement areas, alternate lines shall be installed for rapid connection when required. A flexible pipe at the discharge end will permit placing over a large area directly without re-handling of pipelines. The pipeline shall be firmly supported. (iv) If more than one size of pipe must be used, the smaller diameter pipe shall be placed at the pump end and the larger diameter at the discharge end. (v) When pumping downwards, an air release valve shall be provided at the middle of the top bend to prevent vacuum or air buildup. Similarly, while pumping upwards, a no-return valve shall be provided near the pump to prevent the reverse flow of concrete. (vi) It is essential that direct radio/telecommunication be maintained between the pump operator and the concrete placing crew. Good communication between the pump operator and the batchingplant is also essential. The placing rate shall be estimated by the pump operator so that concrete can be ordered at an appropriate delivery rate. (vii) The pump shall be started for a check run and operated without concrete to ensure that all moving parts are in operation properly. Before placing concrete, the pump shall be run with some grout/mortar for lubricating the line. (viii) When concrete is received in the hopper, the pump shall be run slowly until the lines are completely full and the concrete is steadily moving. A continuous pumping must be ensured, because, if the pump is stopped, concrete in the line may be difficult to move again. (ix) When a delay occurs because of concrete delivery or some form repair works or for any other reason, the pump shall be slowed down to maintain some movement of concrete in the pipe line. For longer delays, concrete in the receiving hopper shall be made to last as long as possible by moving the concrete in the lines occasionally with intermittent strokes of the pump. It is sometimes essential to run a return line back to the pump so that concrete can be re-circulated during long delays. (x) If after a long delay, concrete cannot be moved in the line, it may be necessary to clean out the entire line. However, quite often only a small section of pipe line may be plugged and requires cleaning. The pump operator who know such details as the length of line, age of concrete in the line etc., should be depended upon to aid in deciding the appropriate section to be cleaned. CPWD SPECIFICATIONS 2009

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(xi) When the form is nearly full, and there is enough concrete in the line to complete the placement, the pump shall be stopped and a “go devil” inserted at the appropriate time so that concrete ahead of the go-devil shall be forced completion of the work. The go-devil shall be forced through the pipeline to clean it out. Use of water pressure is a safer method. The go-devil shall be stopped at the discharge end to ensure that water does not spill on the placement area, if air pressure is used, extreme care shall be taken and the pressure must be carefully regulated. A trap shall be installed at the end of the line to prevent the go-devil being ejected as a dangerous projectile. An air release valve shall also be installed in the line to prevent air pressure build up. (xii) It is essential to clean the line after concrete placing operation is complete. Cleaning shall be done in the reverse direction from the form work end to the pump-end where the concrete in the line can be dumped in bucket. After removal of all concrete, all pipe lines and other equipments shall be cleaned thoroughly and made ready for the next use. 5.11.2 Submittals Along with their bid the contractors shall be required to submit the following information regarding the equipments proposed to be used by them:(i) Type, number, capacity, range, mounting, nature of primary power used and the operating weight of pump and mounting. (ii) Manufacturer’s specifications for pipe lines giving pressure ratings, sizes and material for straight and curved sections. (iv) Manufacturer’s certificates. 5.11.3 Sampling and Testing (Materials) 5.11.3.1 Aggregates (i) Supplier of aggregates shall furnish the following information before the material is delivered to site:- Precise location of source from where the material is to be supplied. - Trade group of principal rock type as per table 5.7 below : - Presence or reactive minerals TABLE 5.7 Trade group name of Aggregates to be used for concrete

: Granite, Gabbro, : Dolerite, Rhyolite, Basalt, Quartzite, Gneiss.

(ii) The supplier shall also furnish reports on test results giving the following information for approval to Engineer-in-Charge before delivery of material at site:Specific gravity Bulk density Moisture content Absorption Value Aggregate crushing strength Aggregate impact value Abrasion value 161

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Flakiness index Elongation index Limits of deleterious substances in the aggregate Soundness of aggregate Potential reactivity of aggregates. All tests shall be conducted in accordance with IS 2386 (Part-I to VIII). (iii) Change in quality of aggregate as per trade group name shall not be acceptable in the work. Change in source of aggregates shall also not be acceptable under normal circumstances, even if the aggregate belong to the same trade group. Engineer-in-Charge may with his discretion allow a change in the source. But, in that case, all test mentioned in para 5.8.9.1.2 above shall have to be repeated for the aggregates form the changed source and the test results submitted to Engineer-in-Charge for his approval before the delivery of material at site. (iv) In addition to above, the following tests have to be performed on representative samples from every lot of aggregate after delivery at site. These test results are to be submitted to the Engineer-in-Charge for his approval. Acceptance criteria for aggregates shall be based on the results of this set of tests only. If in the opinion of the Engineer-in-Charge, the test results are not with in permissible limits, the lot of aggregates from which the samples have been obtained for testing shall stand rejected and the material shall be removed from the site. Mandatory tests on Aggregates at site Tests 1. 2. 3. 4. 5.

Nos. of test on each Material or part thereof 3 3 3 3 3

Specific gravity Bulk density Aggregate crushing strength Limits of deleterious substances Aggregate impact value

50 cum of

Mean value of the results from above test shall be taken as the representative value and the acceptance criteria shall be based on these. All test procedures and computations for test results shall be as per IS 2386. (v) All other tests in para iv being in compliance with requirements set in specifications, if only the limits of deleterious substances do not meet the requirements, and attempt may be made to wash the aggregate to bring the limits within permissible values. Under such circumstances, moisture content check shall be made and allowance made before batching. (vi) Apart from mandatory tests specified above, the Engineer-in-Charge may at his discretion, call for any additional tests that he may consider necessary. Sampling, procedure and computations for such test shall be done in accordance with IS 2430 and IS 2386 as applicable. 5.11.3.2 Cement : Supplier of cement shall furnish the following documents before the cement is delivered to site:(i) Certificate confirming that chemical composition and physical characteristics are within the stipulated values for types of cement supplied as per relevant codes. (ii) Certificate confirming that the chloride content in the cement is not in excess of 0.05 percent of mass of cement. (iii) If during subsequent testing of cement supplied in lots any of the properties are found to be outside the acceptable limits, the lot of cement shall be rejected. CPWD SPECIFICATIONS 2009

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(iv) Each 1000 bags or part thereof the cement or each wagon load of cement shall constitute one lot of cement for the purpose of conducting tests at site before cement is accepted. (v) Samples for testing at site shall be taken at random from 2% of the total quantity supplied in one lot. For cement supplied in bags, samples shall be drawn from minimum of 5 bags and the 2% value shall be rounded off to the next higher integer. For bulk cement, sampling shall be done with the help of slotted sampler to be as per IS 3535. (vi) Results of test conducted on samples drawn shall be submitted to the Engineer-in-Charge for his approval. If in the opinion of the Engineer-in-Charge, the test results are not within permissible limits, the lot of cement from which samples have been obtained from testing shall stand rejected and the material shall be removed from site. (vii) Following tests shall be conducted at site on each lot of cement delivered:Mandatory tests 1. Consistency of standard cement paste 2. Initial and final setting time 3. Compressive strength test

Number of test per lot 5 5 each 10

Mean values of the results from the above results shall be taken as the representative value and the acceptance criteria shall be based on these test. All test procedures and computation of test results shall be as per I.S. 4031. (viii) Apart from mandatory tests specified above, the Engineer-in-Charge may at his discretion, call for any additional tests that he may consider necessary. All such tests shall be done on representative samples taken from each lot and testing and computation of test results shall be done as per IS 4031. 5.11.3.3 Water (i) Water to be used in manufacturing and curing of concrete shall be tested before use. All such test results shall be submitted to the Engineer-in-Charge for his approval before water is used. (ii) Manufacturer/ Contractor responsible for curing concrete shall identify and inform the Engineerin-Charge, precisely the location of source of water intended to be used. Each such source of water shall be separately tested. In the event of a change in the source of water all tests specified herein shall have to be repeated. (iii) In the event water is drawn from tube wells or open-wells, water samples shall be tested for seasonal fluctuations in water table or at intervals to be directed by the Engineer-in-charge. (iv) Water sample from each source shall be tested as under:Test Acidity Alkalinity Presence of solids

Number of test for each source 3 3 3

Mean values of the above test shall be taken as the representative value and the acceptance criteria shall be based on these test results. All testing procedure and computation of test results shall conform to IS 3025.

163

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5.11.3.4 Admixtures (i) Suppliers of Admixtures for concrete shall supply the following before any admixtures is approved by the Engineer-in-Charge for their used:Certificate confirming that the use of a particular brand of admixture shall not be harmful to concrete in any way. Certificate confirming the exact dosage of admixture of a particular brand. Certificate stating the specific purpose for which the admixture is to be used. Special precautionary measures to be taken in the manufacturer of concrete when using the particular brand of admixture. Certificate confirming that the admixture conforms to specifications of IS 9103 or to ASTM-C260, ASTM – C10, ASTM – C 595 or to ASTM- C 618. (ii) Engineer-in-Charge at his discretion may require tests to be performed to reconfirm the characteristic properties of any admixture. All such tests shall be done in accordance with IS: 9103. (iii) All tests described in paras 5.4.8 to 5.4.10 above shall be done at the site laboratory or at a laboratory to be identified by the Engineer-in-Charge depending on the test to be conducted. (iv) All test shall be done in the presence of a representative nominated by the Engineer-in-Charge and a representative of the concrete Manufacturer/ Contractor when tests are performed at the site laboratory. All observation and reports of test shall be jointly signed by the two representatives before the test results are submitted to the Engineer-in-Charge. (v) Expenses for all materials used for testing, sampling procedures and testing including preparing reports shall be borne by the concrete Manufacturer/ Contractor. (vi) Rate of concrete is inclusive of cost of admixtures. The contractor shall not be paid anything extra for admixtures required for achieving direct workability without any change in specified water cement ration for RCC/CC work. 5.11.4 Sampling and Testing for Quality Control of Fresh Concrete Fresh concrete shall be tested for (a) Slump (b) Compacting Factor/ Workability (c) Consistency (d) Weight per cubic metre, cement factor and air content 5.11.4.1 Slump (i) For concrete totally mixed in a central plant, slump shall be checked at:(a) Immediately during loading of trucks (b) Point of discharge from the delivery truck (c) Final placement location (d) At placement location the slump measured shall conform to the design slump. Manufacturer of concrete shall adjust for loss of slump in transit and establish the requirements of design mix. All slump measurements shall be done within a period of 20 minutes from the time cement is added to the mixer. Placement contractor shall transport concrete from truck discharge point to actual placement location within 10 minutes of delivery, before the final slump reading is taken at placement location. CPWD SPECIFICATIONS 2009

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(ii) For concrete entirely mixed in transit or for shrink mix concrete, slump reading shall be taken at:(a) Point of discharge from delivery trucks (b) Final placement location In this case also, the slump measured at the final placement location shall conform to the design slump. The placement contractor shall be responsible for transporting concrete from delivery truck discharge point to final placement location within 10 minutes. However, in this case, the truck shall discharge the concrete within 1 hour and 30 minutes from the time cement is added in the mixer and slump measured at point of discharge immediately on delivery. Manufacturer of concrete shall ensure that the final slump measurement corresponds to the ordered slump. (iii) For measuring concrete slump at point of discharge from delivery trucks, samples shall be taken from concrete omitting the first and the last 15% of the load. For concrete delivery of placed by pumping, sampling shall be similar to those specified for delivery trucks. (iv) Slump measurements of ready mix concrete transported by buckets shall be at locations specified in para 5.11.4.1 with same limits on time. Sampling from buckets shall be such that the buckets containing discharge from mixer for the last 15% are omitted. (v) At placement locations, samples for checking slump shall be collected from every 20 cum of concrete or part thereof placed at location for each type to concrete. (vi) For all slump checks in the field at least two recordings shall be made and the average value taken as the recorded slump. (vii) Slump checks for concrete in the laboratory shall be carried out as and when required by the manufacturer of concrete during the mix design stage and during the progress of work for control on field results. (viii) Slump readings shall only be a guideline for concrete consistency and shall not be taken as the acceptability criteria for concrete placed at location. All slump test shall be carried out in accordance with IS 1199. 5.11.4.2 Compacting Factor (i) For concrete whose ordered slump is 50 mm or less, compacting factor test shall be conducted at both field and central batch plant in addition to slump tests mentioned above. (ii) Compacting factor check shall be done in field only at placement location, and shall also be conducted at central batch plant if concrete is totally mixed in plant. (iii) For this test, sampling shall be done as for slump measurements in field and within the same frame as for slump test. (iv) Only one compaction factor test shall be conducted for every 20 cum of concrete or part thereof placed at location for each type of concrete. Since the test is sensitive, every care shall be taken to conduct this test totally in compliance with procedure mentioned in IS 1199. (v) Laboratory tests for determining compacting factor of concrete shall be done as per manufacturer’s requirements for establishing and controlling the design mix of concrete. (vi) Compacting factor test shall not be taken as an acceptance criteria and shall be treated only as a guideline to workability of concrete.

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5.11.4.3 Consistency of Concrete : This test shall be performed only at the batching plant laboratory using a Vee-Bee Consist meter, for determining and predicting the slump of concrete. Number and frequency of these tests shall be based on requirements of the manufacturer of concrete. Care shall be taken in producing mix design of required characteristic strengths of concrete within limits of Vee-BeeDegrees between 1.6 and 4.5 for concrete transported and placed by normal method and between 0.8 and 3.5 for concrete transported and placed by pumping methods. 5.11.4.4 Weight, Cement Factor and Air contents Test : Freshly mixed concrete for every type shall be tested in the batch plant laboratory for each batch of concrete produced to determine weight per cubic metre of freshly mixed concrete, cement factor in concrete and the air content of the concrete. Frequency and number of test shall be finalized by the manufacturer of concrete in consultation with the Engineer-in-Charge for his requirement of the mode of measurement of concrete produced. The Engineer-in-Charge may at his discretion require further tests over and above those specified above in para 5.11.4.1 to be conducted on fresh concrete. The manufacturer and the placement contractor shall have to comply with all such requirements. 5.11.5 Sampling and Testing for Quality Control of Hardened Concrete (i) Test on cube crushing strength of concrete in accordance and compliance with IS 456 and IS 516 shall done as under:(a) Sample of fresh concrete shall be taken from concrete at central batch plant mixer while loading delivery trucks or other transport and also from concrete transported to placement location. (b) Test on specimens made form samples collected at placement location shall be considered as field test specimens and results therefrom shall be the criterion of concrete strength. Test in specimens made from samples at the batch plant shall only be taken as guidelines test. Only in the case of doubtful result, the Engineer-in-Charge may refer to such guideline results for deciding on the quality of concrete. (c) For truck mix concrete and shrink mix concrete guideline test specimens shall be made from samples collected at discharge location from mixing trucks. For this purpose first and last 15% of the load shall be omitted while collecting samples. (d) Frequency of sampling shall be as given below in Table 5.8 for each grade of concrete of different workability’s and for each type of specimens (field test specimens and guideline test specimens) for conducting 28 days crushing strength tests. TABLE 5.8 Quantity of concrete Delivered (cum) Less than 5 6 to 15 31 to 50 51 and above sample for each

Number of samples 1 2 3 4 plus one additional 50 cum or part thereof

Each sample shall be of adequate quantity so that a minimum of 3 specimen cubes can be made test of the sample in accordance with IS 516. (e) All test specimens shall be made compacted cured and tested in compliance with IS 516 and test result interpreted in accordance with IS 456 for acceptance of concrete strength, field specimens test results shall not be less than values given in Table 5.6.

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(f) In addition to 28 day crushing strength test on specimens made at frequencies specified in para 4 above, early strength tests at 7 days shall also be conducted on field specimens as well as guideline test specimens. Frequency of sampling for this set of test shall also be same as those specified in Table 5.8 above. 7 day strength shall conform to values given in Table 5.5. But these test results even if conforming to specified values shall only be taken a guideline values for projecting concrete strength and shall not be construed as conforming to specifications. (g) For each grade of concrete and for all workability conditions with different water – cement ratios and compositions of admixtures, preliminary test shall be conducted for crushing strength on finalization to design mix for each type of concrete. Such test shall be conducted both at 7 days and 28 days under laboratory conditions. Six test specimens shall be made for 7 days test and six test specimens shall be made for 28 days test. Average of the six test results of different periods shall not be less than those specified in Table 5.5. (h) Crushing strengths on cubes shall also be conducted during the process of finalization of concrete design mix. Frequency and number of such tests shall be as per Mix of requirements of concrete manufacturer. (i) All test specimens for conducting crushing strength shall be properly labeled for identification indicating:(i) Date of making specimen (ii) Grade of concrete (iii) Placement location exact (iv) Purchasers order number (j) In addition to crushing strength test on concrete, the Engineer-in-Charge may call for other tests on hardend concrete. The placement contractor and the manufacturer of concrete shall comply with all such instructions. (ii) Non-destructive Tests (a) When the 28 days crushing values on field specimens and/ or specimens and/or specimens made for guideline test fall short of specified values, or in case of doubtful placement of concrete, the Engineer-in-Charge shall call for non-destruction tests on the structure. Such tests may be any one or a combination of the following:ƒ Rebound hammer test ƒ Windsor Penetration Probe test ƒ Pulse velocity (sonic or Ultrasonic) test ƒ Core test ƒ Load test (b) Interpretation of rebound hammer, Windsor Probe and Pulse velocity test results shall rest with the Engineer-in-Charge. (c) Core test, if ordered by the Engineer-in-Charge, shall be done in accordance with IS 516. Samples for such test shall be taken from locations to be identified by the Engineer-in-Charge and such samples shall be collected in compliance with IS:1199. (d) If felt necessary, the Engineer-in-Charge may instruct load testing for any part of the structure based on doubtful concrete strengths. Such test shall be carried out as per details to be provided by the Engineer-in-Charge in consultation with the structural consultants. 167

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(e) The concrete manufacturer/ concrete placement contractor shall arrange for all test to be conducted in accordance with these specifications, including all necessary tools, plants, equipment and material, and shall be responsible for conducting all test at his cost. (f) All test conducted at the filed laboratory shall be carried out by qualified technicians employed by the concrete manufacturer/ concrete placement contractor, in presence of authorized representative of the Engineer-in-Charge. All test reports and observation reports shall be jointly signed by the Engineer-in-Charge authorized representative and the technician conducting such test. (g) Engineer-in-Charge shall alone decide where such tests are to be conducted. He may instruct tests to be conducted at laboratories other than the field laboratory and such instructions shall be followed without claiming extra charges on this account. (h) The Concrete Manufacturer/ Placement contractor shall set up a laboratory at this own expense which shall have facilities, for conducting all necessary field test on materials and field and laboratory test on concrete. The laboratory shall be staffed by the concrete Manufacturer/ Placement Contractor with qualified and experienced scientists and technicians.

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APPENDIX A

CUBE TEST FOR COMPRESSIVE STRENGTH OF CONCRETE MANDATORY LAB TEST (Clause 5.4.9.1) A-0 One sample (consisting of six cubes 15x15x15 cm shall be taken for every 20 cum or part thereof concrete work ignoring any part less than 5cum or as often as considered necessary by the Engineerin-Charge. The test of concrete cubes shall be carried out in accordance with the procedure as described below. A register of cubes shall be maintained at the site of work in Appendix C. The casting of cubes, concrete used for cubes and all other incidental charge, such are curing, carriage to the testing laboratory shall be borne by the contractors. The testing fee for the cubes, if any, shall be borne by the department. A-1 Test Procedure A-1.1 Mould The mould shall be of size 15 cmx15 cmx15 cm for the maximum nominal size of aggregate not exceeding 40 mm. For concrete with aggregate size more than 40 mm size of mould shall be specified by the Engineer-in-charge, keeping in view the fact that the length of size of mould should be about four times the size of aggregate. The moulds for test specimens shall be made of non-absorbent material and shall be substantially strong enough to hold their form during the moulding of test specimens. They shall not vary from the standard dimensions by more than one percent. The moulds shall be so constructed that there is no leakage of water from the test specimen during moulding. All the cube moulds for particular site should, prior to use, be checked for accuracy in dimensions and geometric form and such test should at least be made once a year. Each mould shall be provided with a base plate having a plane surface and made of non-absorbent material. This plate shall be large enough in diameter to support the moulds properly without leakage. Glass plates not less than 6.5mm thick or plain metal not less than 12mm thick shall be used for this purpose. A similar plate shall be provided for covering the top surface of the test specimen when moulded. Note: Satisfactory moulds can be made from machine or steel castings, rolled metal plates or galvanized. A-1.2 Sample of Concrete Sample of concrete for test specimen shall be taken at the mixer or in the case of ready mixed concrete from the transportation vehicle discharge or as directed by Engineer-in-Charge. Such samples shall be obtained by repeatedly passing a scoop or pail through the discharge stream of concrete. The sampling operation should be spread over evenly to the entire discharging operation. The samples thus obtained shall be transported to the place of moulding of the specimen to counteract segregation. The concrete shall be mixed with a shovel until it is uniform in appearance. The location in the work of the batch of concrete this sampled shall be noted for further reference. In case of paving concrete, samples shall be taken from the batch immediately after deposition of the sub grade. At least five samples shall be taken from different portion of the pile and these samples shall be thoroughly mixed before being used to form the test specimen. The sampling shall be spread as evenly as possible throughout the day. When wide changes occur during concreting, additional sample shall be taken if so desired by the Engineer-in-Charge.

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A-1.3 Preparation of Test Specimens The interior surfaces of the mould and base plate shall be lightly oiled before the concrete is placed in the mould. The samples of concrete obtained as described under the test specimen shall be immediately moulded by one of the following methods as indicated below:When the job concrete is compacted by manual methods, the test specimen shall be moulded by placing the fresh concrete in the mould in three layers, each approximately one third of the volume of the mould. In placing each scoopful of concrete the scoop shall be moved around the top edge do the mould as the concrete there sided from it, in order to ensure a uniform distribution of concrete within the mould. Each layer shall be rodded 35 times with 16 mm rod, 60 cm in length, bullet pointed at the lower end. The strokes shall be distributed in uniform manner over the cross section of the mould and shall penetrate into underlying layer. The bottom layer shall be rodded through its depth. After the top layer has been rodded, the surface of the concrete shall be struck off with a trowel and covered with a glass plate at least 6.5 mm thick or a machined plate. The whole process of moulding shall be carried out in such a manner as to preclude the change of the water cement ratio of the concrete, by loss of water either by leakage from the bottom or over flow from the top of the mould. When the job concrete is placed by vibration and the consistency of the concrete is such that the test specimens cannot be properly moulded by hand rolling as described above, the specimens shall be vibrated to give a compaction corresponding to that of the job concrete. The fresh concrete shall be placed in mould in two layers, each approximately half the volume of the mould. In placing each scoopful of concrete the scoop shall be moved around the top edge of the mould as the concrete there slides from it, in order to ensure a symmetrical distribution of concrete within the mould. Either internal or external vibrators may be used. The vibration of each layer shall not be continued longer than is necessary to secure the required density. Internal vibrators shall only be used when the concrete is required to be compacted in layers. In compacting the first layer, the vibrators shall not be allowed to rest on the bottom of the mould. In placing the concrete for top extent that there will be no mortar loss during vibrations. After vibrating the second layer enough concrete shall be added to bring level above the top of the mould. The surface of the concrete shall then the struck off with a trowel and covered with a glass or steel plate as specified above. The whole process of moulding shall be carried out in such a manner as to preclude the alteration of water-cement ratio of the concrete by loss of water, either by leakage for the bottom or over flow from the top of the mould. A-1.4 Curing and Storage of Test Specimen In order to ensure reasonably uniform temperature and moisture conditions during the first 24 hours for curing the specimen and to protect them from damage, moulds shall be covered with wet straw or gunny sacking and placed a storage box so constructed and kept on the work site that its air temperature when containing concrete specimens shall remain 22ºC to 33ºC. Other suitable means which provide such a temperature and moisture conditions may be used. It is suggested that the storage box be made of 25 mm dressed tongued and grooved timber, well braced with battens to avoid warping. The box should be well painted inside and outside and should be provided with a hinged cover and padlock. The test specimen shall be removed from the moulds at the end of 24 hours and stored in a moist condition at a temperature within 24ºC to 30ºC until the time of test. If storage in water is desired, a saturated lime solution shall be used. Note:-

A-1.5 Testing The specimens shall be tested in accordance with procedure as described below:

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(a) The tests shall be made at an age of concrete corresponding to that for which the strengths are specified. (b) Compression tests shall be made immediately upon removal of the concrete test specimen from the curing room i.e. the test specimen shall be loaded in damp condition. The dimensions of the test specimens shall be measured in mm accurate to 0.5 mm. (c) The metal bearing plates of the testing machine shall be placed in contact with the ends of the test specimens. Cushioning materials shall not be used. In the case of cubes, the test specimen shall be placed in the machine in such a manner that the load is applied to sides of the specimens as cast. An adjustable bearing block shall be used to transmit the load to the test specimen. The size of the bearing block shall be the same or slightly larger than that of test specimen. The upper or lower section of the bearing block shall be kept in motion as the head of the testing machine is brought to a bearing on the test specimen. (d) The load shall be applied axially without shock at the rate of approximately 140 kg. per sq.cm. per minute. The total load indicated by the testing machine at failure of test specimen shall be recorded and the unit compressive strength is calculated in kg per sq. cm. using the area computed from the measured dimension of the test specimen. The type of failure and Appearance of the concrete shall be noted.

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APPENDIX B

ADDITIONAL TESTS FOR CONCRETE (Clause 5.4.9.2) B-0 In case the concrete fails when tested as per the method prescribed in Appendix A, one or more of the following check tests may be carried out at the discretion of Engineer-in-Charge to satisfy the strength of the concrete laid. All testing expenditure shall be borne by the contractor, the number of additional tests to be carried out shall be determined by the Engineer-in-Charge. He shall be the final authority for interpreting the results of additional test and shall decide upon the acceptance or otherwise. His decision in this regard shall be final and binding. For the purpose of payment, the Hammering test results only shall be the criteria. Some of the tests are outlined below:B-1 REBOUND HAMMER TEST If a rebound hammer is regularly used by trained personnel in accordance with procedure described in IS 13311 (part II) and a continuously maintained individual charts are kept showing a large number of reading and the relation between the reading and strength of concrete cubes made from the same batch of concrete, such charts may be used in conjunction with hammer readings to obtain an approximate indication of the strength of concrete in a structure for element. If calibration charts are available from manufactures, it can be used. When making rebound hammer test each result should be the average of at least 12 readings. Reading should not be taken within 20mm of the edge of concrete members and it may be necessary to distinguish between readings taken on a trowled face and those on a moulded face. When making the tests on a precast unit, special care should be taken to bed them firmly against the impact of the hammer. B-2 CUTTING CORES This method involves drilling and testing cores from the concrete for determination of compressive strength. In suitable circumstances, the compressive strength of the concrete in the structure may be assessed by drilling cores from the concrete and testing. The procedure used shall comply with the requirements of IS 1199 and IS 516. The points from which cores shall be taken shall be representative of the whole concrete and at least three cores shall be obtained and tested. If the average of the strength of all cores cut from the structure is less than the specified strength, the concrete represented by the cores shall be liable to rejection and shall be rejected if a static load test (B-5) either cannot be carried out or is not permitted by the Engineer-in-Charge. B-3 ULTRASONIC TEST If an ultrasonic apparatus is regularly used by trained personnel in accordance with IS 13311 (part I) and continuously maintained individual charts are kept showing a large number of readings & the relation between the reading and strength of cubes made from the same batch of concrete, such charts may be used to obtain approximate indications of the strength of concrete in the structures. In cases of suspected lack of compaction or low cube strength the results obtained from the ultrasonic test results on adjacent acceptable section of the structures may be used for the purpose of assessing the strength of concrete in the suspected portion. B- 4 LOAD TESTS ON INDIVIDUAL PRECAST UNITS The load tests described in this clause are intended as check on the quality of the units and should not be used as substitute for normal design procedure. Where members require special testing. Such special testing procedures shall be in a accordance with the specification. Test loads shall be applied and removed incrementally. B-4.1 Non Destructive Tests The unit shall be supported at its designed point of support and loaded for five minutes with a load equal to the sum of the characteristic dead load plus one and a quarter time the characteristic imposed CPWD SPECIFICATIONS 2009

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load. The deflection is then recorded. The maximum deflection after application of the load shall be in accordance with the requirements defined by the Engineer-in-Charge. The recovery is measured five minutes after the removal of the load and the load then reimposed. The percentage recovery after the second loading shall be not less than that after the first loading nor less than 90% of the deflection recorded during the second loading. At no time during the tests, shall the unit show any sign of weakness or faulty construction as defined by the Engineer-in-Charge in the light of reasonable interpretation of relevant data. B-4.2 Destructive Tests The unit is loaded while supported at its design point of support and must not fail at its design load for collapse, within 15 minutes of time when the test load becomes operative. A deflection exceeding 1/40 of the test span is regarded as failure of the unit. B-4.3 Special Tests For very large units or units not readily amenable to the above test e.g. columns, the precast parts of composite beams and members designed for continuity or fixity, the testing arrangements shall be agreed upon before such units are cast. B-5 Load Test of Structures or Parts of Structures The test described in this clause are intended as a check where there is a doubt regarding structural strength. Test loads are to be applied and removed incrementally. B-5.1 Age at Tests The test is to be carried as soon as possible after the expiry of 28 days from the time of placing of the concrete. When the test is for a reason other than the quality of concrete in the structure being in doubt, the test may be carried out earlier, provided that the concrete has already reached its specified characteristic strength. B-5.2 Test Load The test loads to be applied for the limit state of deflection and local damage are the appropriate design loads i.e., the characteristic dead and superimposed loads. When the limit state of collapse is being considered the test load shall be equal to the sum of characteristic dead load plus one and a quarter times the characteristic imposed load and shall be maintained or a period of 24 hours. In any of the test temporary supports of sufficient strength to take the whole load shall be placed in position underneath but not in contact with the members being tested. Sufficient precautions must be taken to safeguard persons in the vicinity of the structure. B-5.3 Measurement During Tests Measurements of deflection and crack width shall be taken immediately after applications of the load and, in the case of 24 hour sustained load test, at the end of 24 hour loaded period, after removal of the load and after 24 hour recovery period. Sufficient measurements shall be taken to enable side effect to be taken in account. Temperature and weather conditions shall be recorded during the tests. B-5.4 Assessment of Results In assessing the strength of a structure or a part of the structure following a loading test, the possible effects of variation in temperature and humidity during the period of the test shall be considered. The following requirements shall be met: (a) The maximum width of any crack measured immediately on application of the test load for local damage, is to be not more than 2/3 of the value of the appropriate limit state requirement. (b) For members spanning between two supports the deflection measured immediately on application of the test load for deflection is to be not more than 1/500 of the effective span limits shall be agreed upon before testing cantilevered portions of structure.

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(c) If maximum deflection in mm shown during 24 hour under load is less than 40L2/D where L is effective span in mm and D is overall depth of construction in mm, it is not necessary for the recovery to be measured and the requirement (D) does not apply, and (d) If within 24 hours of the removal of test load for collapse as calculated in clause (a) a reinforced concrete structure does not show a recovery of at least 75 per cent of the maximum deflection shown during the 24 hour under load, the loading should be repeated. The structure should be considered to have failed to pass the test if the recovery after second loading is not at least 75 per cent of the maximum deflection shown during the second loading. B-6 DETERMINATION OF WATER SOLUBLE AND ACID SOLUBLE CHLORIDES IN CONCRETE Determination of water soluble and acid soluble chlorides in Concrete shall be done as per method of test given in IS 14959 (Part 1) which covers volumetric method of test as described below : (a) Quality of Reagents Unless otherwise specified, pure chemicals of analytical reagent grade and distilled water (see IS 1070) shall be used in the test. (b) Nitric Acid (HNO3) Concentrated (Specific Gravity 1.42) Prepare the solution, (6N (approximately), by diluting 38ml of concentrated Nitric acid to 100 ml with distilled water. (c) Ferric Alum(FeNH4 (SO4)2 12 H2O) Dissolve 10 g of ferric alum in 100 ml of distilled water and add 1 ml of Nitric acid. (d) Potassium Chromate 5% Solution Dissolve 5 g of potassium chromate (K2 CrO4) 100 ml of distilled water to form 5% Solution. (e) Nirabenzene (f) Silver Nitrate (AgNO3)Solution, 0.02 N Weigh 1.7 g of silver nitrate, dissolve in distilled water and dilute to 500 ml in a volumetric flask. Standardize the silver nitrate solution against 0.02 N sodium chloride solution using potassium chromate solution as indicator ( 5 percent m/v) in accordance with the procedure given in IS 3025 (Part 32). (g) Ammonium thiocyanate (NH4 SCN) Solution Weigh 1.7 g of ammonium thiocyanate (NH4 SCN) and dissolve in one litre of distilled water in a volumetric flask. Shake well and standardize by titrating with 0.02 N silver nitrate solution using ferric alum solution as an indicator. Adjust the normality exactly to 0.02 N. (h) Sodium chloride (NaCl) 0.02N Weigh 1.1692 g of sodium chloride (NaCl) dried at 105 +/- 2ºC, dissolve in distilled water and make upto 1000 ml in a volumetric flask. (i) Use of Filter Paper (j) In the methods prescribed in this standard, relative numbers of Watman filter paper only have been prescribed since these are commonly used. However, any other suitable brand of filter papers with equivalent porosity may be used. (k) Procedure for Water Soluble Chloride Weigh 1 000+/-5 g of fresh mortar or concrete sample in a 2 litre capacity beaker and add 500 ml of distilled water (chloride free). Stir the mixture vigorously for 15 minutes. After allowing the mixture to stand for 10 to 15 minutes for settling, decant about 200 ml of the supernatant solution CPWD SPECIFICATIONS 2009

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into a clean dry 250 ml capacity beaker. Immediately, filter the solution through Watman filter paper No.1 and collect the filtrate. Pipette 50 ml of filtrate in a 250 ml capacity conical flask. Add 5 ml of 6 N Nitric acid. Add a known volume (X), preferably 25 ml of nitrobenzene. Shake vigorously to coagulate the precipitate. Titrate the excess silver nitrate with 0.02 N ammonium thiocyanate solution until a permanent faint reddish brown colour appears. Note down the volume (Y) of ammonium thiocyanate used. (l) Procedure for Acid Soluble Chloride Weigh about 1000 +/- 5 g of the fresh mortar or concrete sample in a 2 litre capacity beaker and add 50 ml of 6 N nitric acid and 450 ml of distilled water (chloride free) after stirring for few Minutes. Stir the mixture vigorously for 15 minutes. After allowing the mixture to stand for 10 to 15 minutes for settling, decant about 200 ml of the supernatant solution into a clean dry 250 ml capacity beaker. Immediately, filter the solution through Watman filter paper No.1 and collect the filterate. Pipette 50 ml of filtrate in a 250 ml capacity conical flask. Add 5 ml of 6 N nitric acid. Add a known volume ( X ) preferably 25 ml of standard silver nitrate solution. Add 1 ml ferric alum and 5 ml of nitrobenzene. Shake vigorously to coagulate the precipitate. Titrate the excess silver nitrate with 0.02 N ammonium thiocyanate solution until a permanent faint reddish brown colour appears. Note down the volume (Y) of ammonium thiocyanate used. (m) Calculation Calculate the percentage of chloride(acid soluble/water soluble) by mass of mortar or concrete as follows: Chloride, percent = 0.0007 1 (X – Y), Where X = volume of silver nitrate added, in ml; and Y = volume of 0.02 N ammonium thiocyanate consumed. Note: Interference of silver chloride particles (which are generated in situ) in titration by reacting with thiocyanants can be avoided by the addition of nitrobenzenes which forms a film on silver chloride particles.

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APPENDIX C

REGISTER OF WORK TEST OF CONCRETE (Clause A-O of Appendix A) (a)

Name of work

(b) (c) (d) (e) (f)

Name of Contractor Agreement No. Sample No. Identification mark Portion of work any quantity represented by sample Date and time of casting cube Proportion of mix/ grade of concrete

(g) (h)

Concrete mix, (by volume) 1:1:2 1:1.5:3 1:2:4

Compressive strength in kg/cm2 on 7 days 210 175 140

7 Days’ Test (Clause 5.4.10.3) (1) (2) (3)

(4) (5)

Due date of test Cube No. Actual date of test (a) Minimum strength (b) Maximum strength (c) Average strength of three cubes (d) Difference between 3a and 3b (e) Difference in % age in terms of average strength i.e 3b -3a x 100 3c Specified compressive strength of concrete mix used (a) If 3(e) is more than 30% Sample is not acceptable, then 28 days strength test shall be carried out. (b) If 3(e) is equal to or less than 30% then proceed as below:(i) Difference between column 4 specified compressive strength and column 3 (c) i.e., actual average is higher, it will be denoted (+) and (-) if it is less. (ii) Difference in column 5(b) (i) 3(c)- (4) x 100% terms of % age of specified 4 strength (iii) If the difference in column 5(b) Acceptable & strength is considered in (i) is +ve and the same in order terms of % age of specified strength (4) i.e., value of col. 5(b) (ii) is within (+15% range) JE

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EE

REGISTER OF WORK TEST FOR CONCRETE (a) Name of Work

Concrete mix, (By volume)

(b) (c) (d) (e) (f)

Name of contractor Agreement No. Sample No. Identification mark Portion of work any quantity represented by sample (g) Date and time of casting cube (h) Proportion of mix/Grade of concrete

1:1:2 1:1.5:3 1:2:4

Compressive strength kg/cm2 in 28 days 315 265 210

28 Days’ Test (Clause 5.4.10.4) (1) Due date of test (2) Actual date of test (3) Actual compressive strength of cubes (min. no. of cubes to be tested –three) (a) Minimum strength (b) Maximum strength (c) Average strength of three cubes (d) Specified compressive strength of concrete mix used (e) 70% specified strength (f) 130% of specified strength (4) If 3(b) = 3(f) and 3(a) > 3(e) (5) If 3 (c) is more than 3(f) (6) If any test value exceeds 3(f) (7) If 3 (c) > 3(d) but < 3(f) (8) If 3 (c) < 3(d) and > 3(e) (9) If 3(c) < 3(e)

Cube No.

i.e. 70% of 3(d) i.e. 130% of 3(d) Value of 3(c) shall be compressive strength of sample EE may order further investigation It should be restricted to 3(f) for computation of strength Strength is in order and concrete accepted at full rates. Concrete may be accepted at reduced rates in accordance with para 5.4.13.2 Work represented by this sample shall be rejected and action taken as prescribed in clause 5.4.10.4

177

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

APPENDIX D

LIST OF EQUIPMENTS REQUIRED FOR SITE LABORATORY I. Aggregate Testing 1.

2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13.

ITEMS Aggregate Testing

QUANTITY 1.

STANDARD SIEVES (INDIAN STANDARD) (a) Set of coarse sieves 30 cm dia (GI sheet frames) with aperture size. (40 mm, 25 mm, 20 mm, 16 mm, 17.5 mm, 0 mm, 4.75 mm all with lid and pan) (a-1) Motorised sieve shaker for the above sieves (b) Set of fine sieves 20 cm dia of brass with aperture size (4.75 mm, 2.36 mm, 1.18 mm, 600 mic, 300 mic, 150 mic, 75 mic all with lid and Pan) (b-1) Motorised sieve shaker for the above sieves. Flakiness & Elongation index screen Riffle sample divider slot width 25mm

1 set

1 No. 1 set

1 No. 1 No. 1 No.

1 Los Angeles abrasion Testing Machine 1 No. Bulk Density and voids of Aggregates cylindrical metal measures with capacity 1 No. each (3 ltr, 10 ltr, 15 ltr or 20 ltr) Density basket of galvanized wire height 20 cm 1 No. Pycrometer 1000 ml capacity with Brass 1 No. Hot – Air Blower (Hair Dryer) 1 No. Aggregate impact value apparatus with automatic blow counter Hot – plate 1000 to 2000 wells with regulator cum switch 1 Nos. Drying pans (Frying pans) 2 Nos. China clay dishes with dia 10 cm & 15 cm 2 Nos./each Watch glasses for above 10 cm & 15 cm 2 Nos./each

II. Concrete Testing 1. 2. 3. 4. 5. 6 7. 8. 9. 10. 11. 12. 13.

Sieve Brushes Concrete cube moulds 15x15x15cm Ultrasonic Test Equipment Pruning Rods 2 Kg weight length 40 cm and ramming face 25 mm2 Extra Bottom plates for 15 cm cube mould Standard Vibration Table for gauging the cubes Compression Testing Machine with Electricity cum manually operated tamping unit with pressure guage preferable 30 cm dia, 0-150 tonne in 1 tonne divisions. Sensitivity 0.5 tonne. 1 Air content measuring apparatus Slump test Apparatus complete Pocket concrete pernetrometer 0 to 50kg/ sq.cm Baby Mixer Machine G.I. Tray approx 1mx1m with sides 10 cm high for hand mixing of concrete Concrete temperature measuring thermometer with Brass protection sheath 0100 degree centigrade

CPWD SPECIFICATIONS 2009

178

2 Nos. 50 Nos. 1 No. 4 Nos. 6 Nos. 2 Nos. 1 No. 1 No. 3 Nos. 1 No. 1 No. 2 Nos. 2 Nos.

III. Cement Testing 1. 2. 3. 4. 5.

Mortar Cube Moulds 7.07x7.07x7.07 cm Standard sand Grade I,II,III Mortar Cube vibrator Vicate needle apparatus Computer Blaine’s Apparatus

10 Nos. 50 kgs./each 1 No. 1 No. 1 No.

IV. Weighing Equipment 1. 2. 3. 4. 5. 6.

Physical Balance Capacity 200 gms with weight pony Dial type spring balance preferable with zero correction knob capacity 100 kgs reading to ½ kg. Counter scale capacity 1 kg and 10 kg Weighing platform capacity 100 kg Iron Weight of 5 kg, 2 kg, 1 kg, 500 gm, 200 gm, 100 gm Brass Weight of 50 gm, 20 gm, 10 gm, 5 gm, 2 gm, 1 gm

V. Water Measuring

5 litres, 2 litres, 1 litre, ½ litre

1 No. 2 Nos. 1 No./ each 1 No. 2 No./each 2 No./each 5 Nos./each

VI. Glass and Plastic Ware 1. 2. 3. 4.

Measuring cylinder TPX or Poly propylene capacity 100 ml, 500 ml, 250 ml, 100 ml Pyrex, corning or Borosil beakers with cover capacity 500 ml, 200 ml, 50 ml Wash Bottles capacity 500 ml Thermometers 1-100 degree centigrades/ max. and Min/ Dry and wet with table

2 Nos./each 2 Nos./each 2 Nos./each 1 No.

VII. Laboratory Tools 1. 2. 3. 4. 5. 6. 7. 8.

Set of box spanner ratchet Hammer 1lb Rubber Hammer Hacksaw with 6 blades Measuring tape 2 mtr Depth gauge 20cm Steel Foot Plate Vernier Calliper

2 Nos. 2 Nos. 2 Nos. 1 Nos. 2 Nos. 2 Nos. 2 Nos. 2 Nos.

VIII. Miscellaneous Items 1. 2. 3. 4. 5. 6.

Trowels made from saw blade, 3 mm thick 16x10cm wooden handle Showels & Spade Steel plates 5 mm thick 75x75 cm Plastic or G.I. Buckets 15 ltr, 10 ltr, 5 ltr Wheel Barrow Floor Brushes, hair dusters, scrappers, wire brush, paint brushes, shutter steel plat oil, kerosene with stove etc.

179

6 Nos. 6 Nos./each 2 Nos. 2 Nos. 3 Nos. 3 Nos.

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

ANNEXURE – A (Clause 5.9.3) SAMPLING OF CONCRETE After the truck mixer has re-mixed its delivery on site, allow at least the first one-third of a m3 of concrete to be discharged prior to taking any samples. Take at least 4 incremental samples from the remainder of the load avoiding sampling the last cubic metre of concrete. Thoroughly re-mix this composite sample either on a mixing tray or in the sampling bucket and proceed with the required testing. ANNEXURE – B (Clauses 5.9.4.2 & 5.9.4.3) CONCRETE MIX INFORMATION TO BE SUPPLIED BY THE PURCHASER RMC : ……………………………………………………………………………….. Contractor : …………………………………………………………………………. Site : …………………………………………………………………………………. MIX CODE Grade (N/mm2) (Characteristic strength) Minimum Cement Content (kg./m3) Mineral Additives (Pulverized fuel ash/Slag/Others) (kg/m3) Maximum Free water Cement Ratio Nominal Maximum Aggregate size Cement Type and Grade (if preferred) Target workability (Slump) (mm) Target workability at site Maximum Temperature of Concrete at the time of placing Class of sulphate Resistance (if applicable ) Exposure condition (if applicable) Class of finish (if applicable) Mix Application Method of Placing Any other requirements (early strength workability retention, permeability testing, chloride content restriction, maximum cement content, etc. ) Concrete Testing (Frequency) Material’s Testing (any non-routine requirements) Alternatives to be offered: Yes/No Method of Curing to be used by contractor Quantity (m3) Note : Additional proforma for further information may be used, such as for specific test rates to be achieved for concrete or raw materials, exact method statements of the contractors proposed site practice. CPWD SPECIFICATIONS 2009

180

ANNEXURE – C (Clauses 5.9.6.2 and 5.9.6.3) CALIBRATION AND WEIGHING EQUIPMENT ACCURACY C-1. The following limits shall apply to all ready-mixed concrete plants : (a) The accuracy, sensitivity and arrangement of the weighing devices shall be such as to enable the materials to be batched within the following tolerances : (1) Cement, mineral : Within + 2 percent of the quantity of the constituent Admixtures being measured. (2) Aggregate, chemical : admixtures and water

Within + 3 percent of the quantity of the constituent being measured.

(b) Analogue scales shall have scale increments not exceeding 5 kg. for cement and mineral admixtures, 25 kg. for aggregate and 2 kg. for water. (c) Preset controls shall be calibrated in increments not exceeding 5 kg. for cement and mineral admixtures, 10 kg. for aggregate and 2 kg. for water. (d) For continuous mixer plants calibration shall be in increments not exceeding 10 kg./m3 for cement and mineral admixtures, 25 kg./m3 for aggregates and 10 l/m3 for water. (e) Digital readous shall have a scale increments not exceeding 2 kg. for cement and mineral admixtures, 10 kg. for aggregate and 10 for water. (f) At the time of installation, or reconditional the accuracy of the indicated mass at any point on the scale shall be within 0.25 percent of the full scale reading. (g) Any other time during the masonry operation the accuracy shall be within 0.50 percent of the full scale reading. (h) Chemical Admixture dispensers shall have scale increment for exceeding. Ranger of scale in kg/l 0.1 – 0.5 0.5 - 1.0 1.0 – 10.0 more than 10.0

Scale increment in Kg/l 0.01 0.02 0.2 0.4

(i) All weighing and measuring equipment shall be tested and calibrated over its full working range at the following intervals : (1) Mechanical /knife edge systems : At least once every two month (2) Electrical /load cell systems

:

At least once every three months

Adequate and identified facilities shall be provided for the application of the test loads. (j) In the case of batch weighing systems testing and calibration shall be based on the application test loads to the weigh hoppers. (k) Checks on continuous weigh systems shall be based on comparison of preset quantities with those actually produced. 181

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

(l) To achieve the required accuracy of calibration, a minimum of 500 kg. of stamped weights are required, except that for low capacity scale an acceptable limit on the total mass of calibration weight would be 20 percent of the scale capacity. (m) When calibration of weighing equipment is carried out all personnel involved should be competent and fully trained, the procedures should be fully documented, and special attention should be paid to the health and safety aspects of the procedure.

ANNEXURE – D

DELIVERY TICKET INFORMATION (Clause 5.9.6.5) D-1 The following information shall be included in the delivery ticket to accompany the load to the purchaser : (a) Name or number of the ready-mixed concrete depot (b) Serial number of the ticket (c) Date (d) Truck number (e) Name of the Purchaser (f) Name and location of site (g) Grade or mix description of the concrete (h) Specified target workability (i) Minimum cement content (if specified) (j) Type of cement and grade (if specified) (k) Maximum free water-cement ratio (if specified) (l) Nominal maximum size of aggregate (m) Generic Type or name of any chemical and mineral admixtures included. (n) Quantity of concrete in m3 (o) Time of loading (p) Signature of the plant operator (q) A statement warning the purchaser of the precautions needed to be taken when working with cement and wet concrete. D-2 On site the following information will be added. : (a) Time of arrival on site. (b) Time when discharge was completed. (c) Any water/admixture added by the supplier to meet the specified workability. (d) Any extra water /admixture added at the request of the purchaser of the concrete, or his representative, and his signature. (e) Pouring location. (f) Signature of the purchaser or his representative conforming discharge of the load.

CPWD SPECIFICATIONS 2009

182

TYPICAL SET UP OF STEEL WALL FORM WORK Sub Head : R.C.C. (Form Work) Clause : 5.2.3.6

Fig. 5.1A : Single Sided Wall Form (Adjustable)

CLIP

Fig. 5.1B : Double Sided Wall Form All Members are of Steel

Fig. 5.1 : Typical Set Up of Steel Wall Form Work

183

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

WALL FORM Sub Head : R.C.C. (Form Work) Clause : 5.2.3.6

CLIPS

All Members are of Steel

Fig. 5.2 : Adjustable Curved Wall Form (Double Sided)

CPWD SPECIFICATIONS 2009

184

TYPICAL FIXING DETAILS OF WALL TIES Sub Head : R.C.C. (Form Work) Clause : 5.2.3.6.

CO IL T IE LENGTH 75 LONG BOLT

PLASTIC

CONES

WASHER

37.5 30

SOLDIER

37.5 30

COIL PENETRATION

WALL THICKNESS

47.5

47.5

Fig. 5.3A : Wall Tie for Two Sided Shuttering All Members are of Steel WALL TUBES WALL TIE

CHANNEL SOULDIER 2.5 M LONG WALL FORM PANELS A - ASSEMBLY CLIP B - BRIDGE CLIP S - SINGLE CLIP

CHANNEL SOULDIER

D

50 LAP

WALLING TUBE

C

C 1ST POUR

100 STARTER

2ND POUR

3RD & SUBSEQUENT POUR

ELEVATION

175

E

500 500

C G

250

1000

E

50 LAP

C=175 D=1125 E=1250 F=1375 G=2500

175

C

Fig. 5.3B : Position of Wall Ties & Walling Tubes (Shuttering for 1st Pour should be properly Strutted by Rakers)

Drawing not to scale All dimensions are in MM

Fig. 5.3 : Typical Fixing Details of Wall Ties 185

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

TYPICAL STANDARD UNITS OF FORM WORK (CENTRING & SHUTTERING) Sub Head : R.C.C. (Form Work) Clause : 5.2.3

A HF

LEDGER TUBE

1000

200

400

1000

200

DETAILS AT A

DETAILS OF H FRAME UNIT

200

1000

B

D

800

1000

KNOCK TO DROP

ADJ. STIRRUP HEAD D

75

C

75

DROP HEAD

3M

2M

2.4 M

E - VERTICALS (IN DIFFERENT HEIGHTS)

All Members are of Steel All dimensions are in MM Drawing not to scale

Fig. 5.4 : Typical Standard Units of Form Work CPWD SPECIFICATIONS 2009

186

1.2M

TYPICAL COMPONENTS OF FORM WORK Sub Head : R.C.C. (Form Work) Clause : 5.2.3.2

ANGLE TRANSOME

DIAGONAL

TUBULAR TRANSOM/ LEDGER/HANDRAIL

B

A HOP-UP BRACKET

C ADJUSTABLE BASE

ANGLE TIE

E

D SCAFFOLD BOARD

F

FIXED BASE PLATE

H

G CLIP LOCK

SPIGOT LOCK

COLLAR-GRIP

J

I

K

Fig. 5.5 : Typical Components of Form Work

187

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

TYPICAL ARRANGEMENT OF COLUMN FORM WORK Sub Head : R.C.C. (Form Work) Clause : 5.2.3.2

CORNER ANGLE BRACKET

Fig. 5.6A : Four Sides Adjustable Column Form

CORNER ANGLE BRACKET EXTERNAL CORNER ANGLE

Fig. 5.6B : Two Sides Adjustable Column Form

SINGLE CLIP

TUBE

THROUGH TIE/WIRE TIE

Fig. 5.6C : Column Form with Adjustable Shuttering Wall Form Type Panels All Members are of Steel

Fig. 5.6 : Typical Arrangement of Column Form Work

CPWD SPECIFICATIONS 2009

188

TYPICAL COLUMN SHUTTERING

Sub Head : R.C.C. (Form Work) Clause : 5.2.3.2

All Members are of Steel

Fig. 5.7 : Typical Column Shuttering

189

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

TYPICAL DETAIL OF BEAM HEAD AND STIFFNER

Sub Head : R.C.C. (Form Work) Clause : 5.2.3.3

BEAM HEAD

A

BEAM HEAD

C

BEAM HEAD PROP ASSEMBLY OF BEAM HEAD OVER PROP B

STIFFNER VARYING WIDTH

38 MM STIFFNER 10 MM PLAN OF FLOOR (SLAB) FORMS

FLOOR FORMS (OUT OF 14 GAUGE M.S. SHEET) (ADJUSTER FLOOR FORMS AVAILABLE IN VARIOUS SIZES

D

E

All Members are of Steel

Fig. 5.8 : Typical Detail of Beam Head and Stiffner

CPWD SPECIFICATIONS 2009

190

TYPICAL DETAILS OF MULTI STAGE SHUTTERING Sub Head : R.C.C. (Form Work) Clause : 5.2.3.4

STEEL CENTRING

BEAM HEAD

SHUTTERING

SUSPENDED FLOOR/SLAB TO BE CAST

PROPS./ VERTICALS

HEIGHT < 3.5 M

HEIGHT< 3.5 M

All Members are of Steel

Fig. 5.9A : Suspended Floor – Multi Stage Shuttering (Vertical Section)

TRANSOM VERTICALS

DIAGONALS

Fig. 5.9B Fig. 5.9 : Typical Details of Multi-State Shuttering 191

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

DETAILS OF EXPANSION JOINTS (IN VARIOUS LOCATIONS)

5

CM

Sub Head: R.C.C. Clause : 5.4.5

10 MM WIDE JOINTS

GROOVE AT R.C.C. -MASONRY JUNCTION

Fig. 5.10 : Expansion Joints in Long Sun Shade

R.C.C. COPING

CRAFT PAPER OR BITUMEN PAINTING

BITUMEN PAINTING LIME TERRACING/MUD PHUSKA

BRICK TILE

BITUMEN FILLER CEILING PLASTER R.C.C. BEAM R.C.C. SLAB METAL CRADLE A.C. SHEET

RAWL PLUG & SCREWS WITH OVAL SHAPED SLOT & WASHER RAWL PLUG & SCREWS

Fig. 5.11 : Details of Raised Type Expansion Joint at Roof

CPWD SPECIFICATIONS 2009

192

EXPANSION JOINTS (CONTD.) Sub Head : R.C.C. Clause : 5.4.5 R.C.C. PRECAST TILE 25 MM THICK TO MATCH THE FLOOR FINISH & LAID OVER A COAT OF HOT BITUMEN 12 MM GAP FILLED WITH JOINT FILLER

R.C.C. SLAB METAL CRADLE FILLED UP WITH BITUMEN FILLER (ABOVE) PLASTER R.C.C. BEAM A.C. SHEET RAWL PLUG & SCREWS

RAWL PLUGS & SCREWS WITH OVAL SHAPED SLOT & WASHER

Fig. 5.12 : Typical Details of Expansion Joint at Floor R.C.C. COPING 75 MM THICK THROATING BITUMEN PAINTING BRICK TILES MUD PHUSKA/LIME CONC. R.C.C. SLAB

C.C. GOLA

BITUMEN FILLER

GROOVE

METAL CRADLE

BEARING PLASTER WITH A THICK COAT OF LIME WASH OR KRAFT PAPER

25 MM GAP

Fig. 5.13 : Typical Details of Expansion Joint at Wall & Beam Junction

BRICK WALL PLASTER R.C.C. CANTILEVER SLAB EMBEDDED IN MASONRY AT ONE END, FREE AT THE OTHER END

MASONRY TO BE CONSTRUCTED AFTER PLACING CANTILEVER SLAB C.C. GOLA

SKIRTING FLOOR FINISH MUD PHUSKA BITUMEN FILLER METAL CRADLE R.C.C. BEAM 25 MM GAP

PLASTER

R.C.C. SLAB

Fig. 5.14 : Typical Details of Expansion Joint at Roof & Floor Junction

193

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

EXPANSION JOINTS (CONTD.) Sub Head : R.C.C. Clause : 5.4.5 A. TWIN BEAM WITH TWIN COLUMNS Twin Beams

A

Twin columns 150 Copper cradle for beam External face

PLAN

A

Twin columns

Twin Beams

300

Mud fuska laid to slope

Flooring R.C.C. Slab

R.C.C. Slab

R.C.C. Beam Plaster

12 mm open joint in floor staggered from expansion joint filled with bitumen

D Gap 25

D

Gap 12

25

SECTION A – A ON ROOF

SECTION A – A ON FLOOR

Fig. 5.15 : Twin Beam with Twin Columns B. SLAB & T-BEAM CONSTRUCTION OF LONG LENGTH (T-Beam changed into rectangular beam to provide intermediate expansion joint) 6 mm expansion joint filled with bitumen filler

Flooring R.C.C. Slab

Bitumen felt

Unfilled gap R.C.C. Rectangular Beam

12 mm expansion joint filled with bitumen filler or impregnated fibre board

T-Beam

Fig. 5.16 : Slab & T-Beam Construction of Long Length C. LONG VERANDAH SLAB A

D. LONG WATER-RESERVOIR SLAB A

12000-13000

A

A

12000-13000

12

12 PLAN

KEY PLAN Butt joint in floor & slab Flooring R.C.C. Slab Ceiling plaster

Bitumen felt

SECTION A – A

PART SEC. A–A

Fig. 5.17 : Long Verandah Slab A B C D E F

Fig. 5.18 : Long Water Reservoir Slab

Hot bitumen painting @ 1.7 k.g/sqm. Bitumen filler Rawl plugs & 50 mm screws @ 300 mm c/c Asbestos sheet 150 mm wide or P.V.C. sheet Rawl plugs & screws with oval shaped slot & washers @ 300 mm c/c Copper cradle

CPWD SPECIFICATIONS 2009

Earth filling R.C.C. Slab Plaster 6 mm

194

Drawing not to scale All dimensions are in mm

EXPANSION JOINTS (CONTD.) Sub Head : R.C.C. Clause : 5.4.5 RAWL PLUG & SCREW WITH OVAL SHAPED SLOT & WASHER

200 MM ASBESTOS CEMENT FLAT SHEET OR ALUMINIUM PLATE OR SIMILAR MATERIAL RAWL PLUG & SCREW

12 MM GAP

R.C.C. COLUMN INSIDE PLASTER

25 MM GAP

Fig. 5.19 : Typical Details of Expansion Joint Covering on Outer Face of Columns (Plan) STEEL OR ALUMINIUM ANGLE FIXED WITH RAWL PLUG & 50 MM SCREW @ 300 MM C/C 12 MM GAP

BRICK WORK

PLASTER

25 MM GAP

R.C.C. COLUMN

Fig. 5.20 : Typical Details of Expansion Joints at Corner Column JOINT FILLER

EXPANDEX BOARD SEALING COMPOUND COLUMN

Fig. 5.21 : Typical Details of Expansion Joint at Isolated Twin Columns REINFORCEMENT

P.V.C. WATER STOP/BAR

JOINT FILLER DISCONTINUTY IN BOTH CONCRETE & STEEL

Fig. 5.22 : Expansion Joint Subjected to Water Pressure (For water Tanks) 195

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

EXPANSION JOINTS (CONTD.) Sub Head : R.C.C. Clause : 5.4.5

FLOORING/MUD PHUSKA WITH TILES

BUTT JOINT IN THE FLOOR STAGGERED FROM EXPANSION JOINTS

50 TO 100 UNFILLED GAP AT TOP C R.C.C. SLAB R.C.C. BEAM

BED PLATE

GROOVE

GROOVE

A

B

B

B. INTERMEDIATE WALL WITH FLOOR BEAM

A. END WALL WITH ROOF/ SUSPENDED FLOOR SLAB FLOORING/MUD PHUSKA WITH TILES

BITUMEN FELT 25 TO 40 UNFILLED 300 GAP AT TOP

FLOORING

C R.C.C. SLAB CEILING PLASTER B

GROOVE

A

GROOVE

B

D. INTERMEDIATE WALL WITH FLOOR SLAB

C. END WALL WITH ROOF/ SUSPENDED FLOOR SLAB

MUD PHUSKA COVERED WITH TILES LAID TO SLOPE BRICK LAID WITH VERTICAL JOINT IN MORTAR

C

A

SEALING COMPOUND

JOINT FILLER

GROOVE B

WALL

WALL

PLASTER METAL SHEET

E. INTERMEDIATE WALL WITH ROOF SLAB

25 MM GAP FLAT ASBESTOS CEMENT SHEET OR ANY OTHER EQUALLY SUITABLE MATERIAL 150 MM WIDE

F. EXPANSION JOINT USING JOINT FILLER AND SEALING COMPOUND A B C

12 MM EXPANSION JOINTS FILLED WITH BITUMEN FILLER OR IMPREGNATED FIBRE BOARD 6 MM CEMENT PLASTER 1:3 (1C : 3F. SAND) FINISHED WITH A FLOATING COAT OF NEAT CEMENT AND A THICK COAT OF LIME WASH OR LAID WITH KRAFT PAPER HOT BITUMEN PAINTING @ 1.7 K.G./SQM. IN CASE OF ROOF SLAB/BEAM

C

HOT BITUMEN PAINTING @ 1.7 KG./SQM. BELOW BRICK WALL ONLY ON SUSPENDED FLOOR BEAM/SLAB

Drawing not to scale All dimensions are in mm

Fig. 5.23 : Expansion Joint (Contd.)

CPWD SPECIFICATIONS 2009

196

SEISMIC SEPARATION JOINTS Sub Head : R.C.C. Clause : 5.4.5 SHEET METAL FLASHING

PRE-CAST SLAB/TILES

BITUMEN

RUBBERISED PAD

RECTANGULAR BAR FLOORING

FLAT BAR SET IN FORMS

R.C.C. SLAB CEILING PLASTER

MASTIC

GAP

GAP

RAWL PLUG WITH OVAL SHAPED SLOT

RAWL PLUG & SCREW

A.C. SHEET

Fig. 5.24: Seismic Separation at Floor Level R.C.C. COPING BITUMEN PAINTING

LIME TERRACING/MUD FUSKA

THROATING C.C. GOLA

BRICK TILES

R.C.C. SLAB CEILING PLASTER FILLED UP WITH BITUMEN FILLER METAL CRADLE R.C.C. BEAM

GAP

GAP RAWL PLUG & SCREWS

RAWL PLUG WITH OVAL SHAPED SLOT A.C. SHEET

Fig. 5.25 : Seismic Separation Joints Detail at Roof

197

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

CONSTRUCTION JOINTS Sub Head : R.C.C. Clause : 5.4.4

A. PROHIBITED JOINT IN SLAB (Clause - 5.4.4.3)

E. JOINT IN BEAM OR SLAB

C.C. FLOORING R.C.C. BASE/LEAN CON B. JOINT IN SLAB (STOP BOARD SLOTTED TO TAKE HORIZONTAL REINFORCEMENT)

C. STOP – BOARD

F. JOINT IN FLOORING FOR WATER RESERVOIRS

PLAN G. JOINT IN MONOLITHIC R.C.C. SLAB AND BEAM CONST.

R.C.C. SLAB SECONDARY BEAM MAIN BEAM D. KEYED JOINTS IN WALLS (WITH STOP-BOARD FITTED WITH 25 X 25 CHAMFER PIECE AND SLOTTED TO TAKE HORIZONTAL BARS)

1

H. SECTION A-A

REPRESENTS FIRST PLACING OF CONCRETE

2. REPRESENTS SUBSEQUENT PLACING OF CONCRETE

Drawing not to scale All dimensions are in mm

Fig. 5.26 : Construction Joints

CPWD SPECIFICATIONS 2009

198

ENCASING ROLLED STEEL SECTION Sub Head : R.C.C. Clause : 5.5.2 LAP NOT LESS THAN 100

50

EXPANDED METAL OF UNGALVANIZED WIRE MESH

R.S. JOIST

Fig. 5.27 : Steel Column 5 DIA WIRE HANGER AT 1200 C/C

R.C.C. SLAB

EXPANDED METAL OR UNGALVANIZED WIRE MESH

R.S. JOIST

25 25

Fig. 5.28 : Steel Beam with Slab Normally Cement Concrete 1 : 2 : 4 (1 Cement : 2 Coarse Sand : 4 Graded Stone Aggregate 12.5 Nominal Size) shall be used. Drawing not to scale All dimensions are in mm

199

SUB HEAD 5.0 : REINFORCED CEMENT CONCRETE WORK

CPWD SPECIFICATIONS 2009

200

SUB HEAD : 6.0

BRICK WORK

CONTENTS Clause No.

Brief Description List of Mandatory Tests

Page No. 205

List of Bureau of Indian Standard Codes

206

6.0

Terminology

207

6.1

Bricks/ Brick Tiles/ Brick Bats/ Mechanized Autoclave Fly Ash Lime Brick

208

6.2

Brick Work

214

6.3

Brick Work in Arches

219

6.4

Half Brick Work

221

6.5

Brick Tile Work

221

6.6

Honey Comb Brick Work

221

6.7

Joining Old Brick Work with New Brick Work

221

6.8

Moulding and Cornices

222

6.9

Brick Work under Water and Foul Conditions

223

6.10

Exposed Brick Work

223

6.11

Cavity Wall

224

6.12

Gypsum Partition Panels

225

6.13

Brick Edging

225

Appendix A

Test for Dimensional Tolerance

226

Appendix B

Test for Compressive Strength

227

Appendix C

Test for Water Absorption

228

Appendix D

Test for Efflorescence

229

Fig. 6.1

Brick Work

230

Fig. 6.2

Brick Pillars

231

Fig. 6.3 & 6.4

Brick Bonds

232

Fig. 6.5

Brick Work in Arches.

234

Fig. 6.6

Brick Work in Cavity Walls

235

203

SUB HEAD 6.0 : BRICK WORK

CPWD SPECIFICATIONS 2009

204

LIST OF MANDATORY TESTS Sl. No.

Material

Clause

Test

Field/ laboratory Test

Test Procedure

(i)

Bricks/ Brick Tiles

6.1.3, 6.1.4, 6.1.5

Laboratory

Appendix A, B, C & D of Chapter 6

(ii)

Sewer Bricks

6.1.4

Laboratory

Appendix A, B, C & D of Chapter 6

As per Table 6.3 and 6.4

(iii)

Burnt clay perforated building bricks

6.1.5

Testing of Bricks/Brick Tiles for dimensions, Compressive strength, Water absorption and efflorescence Dimensions, Compressive strength, Water absorption and Efflorescence --do--

-- do --

-- do--

-- do--

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Minimum Qty. of material for carrying out test As per Table 6.3 and 6.4

SUB HEAD 6.0 : BRICK WORK

LIST OF BUREAU OF INDIAN STANDARDS CODES S. No. 1. 2. 3. 4. 5. 6.

IS. No. IS 712 IS 1077 IS 1200 (Part 3) IS 2212 IS 2222 IS 2849

7. 8. 9. 10. 11. 12. 13.

IS 3495 IS 3812 IS 4139 IS 4885 IS 5454 IS 12894 IS 13757

CPWD SPECIFICATIONS 2009

Subject Specification for building limes. Common burnt clay building bricks. Method of measurements of brick works Code of practice for brick work. (1st Revision) Specification for burnt clay perforated building bricks. Specification for non load bearing gypsum partition blocks, (Solid and hollow types) Method of test for burnt clay building bricks. Specification for fly ash for use as pozzolana and admixture. Specification of calcium silicate bricks Specification for sewer brick Methods of sampling of clay building bricks. Pulverized fuel ash lime bricks specification, Specification of burnt clay fly ash bricks.

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6.0 BRICK WORK 6.0. TERMINOLOGY Bond The arrangement of the bricks in successive courses to tie the brick work together both longitudinally and transversely. The arrangement is usually designed to ensure that no vertical joint of one course is exactly over the one in the next course above or below it, and there is greatest possible amount of lap. Bed Joint Horizontal joint in brick work or masonry. Closer Any portion of a brick used in constructing a wall, to close up the bond next to the end brick of a course (See Fig. 6.3). Coping or Weathering The cover applied over or the geometrical form given to a part of structure to enable it to shed rain water. Corbel A cantilever projecting from the face of a wall to form a bearing (see Fig. 6.1D) Cornice Horizontal or ornamental feature projecting from the face of a wall (see Fig. 6.1D) Course A layer of bricks including bed mortar. Cross joint A joint other than a bed joint normal to the wall face. Efflorescence A powdery incrustment of salts left by evaporation. This may be visible on the surface or may be below surface. In the latter case, this is termed as crypto Efflorescence. Header A brick laid with its length across the wall. Indenting The leaving recesses into which future work can be bonded. Jamb The part of the wall at the side of an opening. Joint A junction of bricks. Jointing The operation of finishing joints as the masonry work proceeds. Pier A thickened section forming integral part of the wall placed at intervals along the wall primarily to increase the stiffness of the wall or to carry a vertical concentrated load. The thickness of a pier is the over all thickness including the thickness of the wall, or when bonded into one leaf of a cavity wall the thickness obtained by treating this leaf as an independent wall (see Fig. (6.1A, 6.1B)). 207

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Pillar Pillar means a detached masonry support. This can be rectangular, circular, elliptical etc. In case of rectangular pillar, the breadth shall not exceed three times the thickness and thickness itself shall not exceed more than thrice the length of brick (See Fig. 6.1C). Quoin An external corner in brick work, the term may also denote the brick used to form the quoin. Scaffolding A temporary erection of timber or steel work used in the construction, alteration, demolition or repairs of a building to support or to attend of the hoisting or lowering of workmen, their tools and materials. Scaffoldings are of two types, namely single and double scaffoldings. Single scaffolding consists of a row of verticals connected to wall by horizontal supported on and tied to the structure. Double scaffolding consists of two rows of verticals secured or leashed together with horizontal and diagonal bracings forming essentially a structure independent of the building. It may also connect to the structure at convenient points for the sake of better stability. Sill A brick work forming the lower boundary of door or window opening (see Fig. 6.1D). Spandrel The space between the haunches and the road decking of an arch. Strecher A brick laid with its length in the direction of the wall. String course A horizontal course projecting from a wall usually introduced at every floor level or windows or below parapet for imparting architectural appearance to the structure and also keeping off the rain water. (see Fig. 6.1D). Templet A pattern of sheet metal used as a guide for setting out specific section and shape. Toothing Bricks left projecting in alternate courses to bond with future work. Wall joint A joint parallel to the wall face. 6.1 BRICKS/BRICK TILES/BRICK BATS/MECHANIZED AUTOCLAVE FLY ASH LIME BRICK Bricks used in the masonry may be of the following type. (a) The Common Burnt Clay Bricks shall conform to IS:1077 and shall be hand moulded or machine moulded. They shall be free from nodules of free lime, visible cracks, flaws warpage and organic matter, have a frog 100 mm in length 40 mm in width and 10 mm to 20 mm deep on one of its flat sides. Bricks made by extrusion process and brick tiles may not be provided with frogs. Each brick shall be marked (in the frog where provided) with the manufacturer’s identification mark or initials. (b) Fly Ash Lime Bricks (FALG Bricks) : The Fly Ash Lime Bricks (FALG Bricks) shall conform to IS 12894. Visually the bricks shall be sound, compact and uniform in shape free from visible cracks, warpage, flaws and organic matter. The bricks shall be solid and with or without frog on one of its flat side. Fly Ash: Fly ash shall conform to IS 3812. CPWD SPECIFICATIONS 2009

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Note: This item will be operated only for load bearing structure upto 2 storeys and for non-load bearing walls 23 cms thick for multi-storeyed building's. Bottom ash used as replacement of sand shall not have more than 12% loss on ignition when tested. Sand: Deleterious materials, such as clay and silt in the sand shall preferably be less than 5%. Lime: Lime shall conform to class ‘C’ hydrated lime of IS 712. Additives: Any suitable additive considered not detrimental to the durability of bricks may be used. (c) Clay Fly Ash Bricks: The clay fly ash bricks shall conform to IS 13757. The bricks shall be sound, compact and uniform in shape and colour. Bricks shall have smooth rectangular faces with sharp and square corners. The bricks shall be free from visible cracks, flaws, warpage, nodules of free lime and organic matter, the bricks shall be hand or machine moulded. The bricks shall have frog of 100 mm in length 40 mm width and 10 to 20 mm deep on one of its flat sides. If made by extrusion process may not be provided with frogs. Fly Ash shall conform to grade I or grade II of IS 3812. (d) Calcium Silicate Bricks: The bricks shall conform to IS 4139. The Calcium silicate bricks shall be sound, compact and uniform in shape. Bricks shall be free from visible cracks, warpage, organic matter, large pebbles and nodules of free lime. Bricks shall be solid and with or without frog. The bricks shall be made of finely grounded sand siliceous rock and lime. In addition limited quantity of fly ash conforming to IS 3812 may be used in the mix. These bricks are also known as Fly Ash Sand Lime bricks in the construction industry. (e) Tile Brick: The bricks of 4 cm height shall be moulded without frogs. Where modular tiles are not freely available in the market, the tile bricks of F.P.S. thickness 44 mm (1-3/4") shall be used unless otherwise specified. (f) Brick Bats: Brick bats shall be obtained from well burnt bricks. (g) Mechanized Autoclave Fly Ash Lime Brick: These bricks shall be machine moulded and prepared in plant by appropriate proportion of fly ash and lime. The autoclave fly ash bricks shall conform to IS 12894. Visually, the bricks shall be sound, compact and uniform shape, free from visible cracks, warpage and organic matters. The brick shall be solid with or without frog, and of 100/80 mm in length, 40 mm width and 10 to 20 mm deep one of its flat side as per IS 12894. The brick shall have smooth rectangular faces with sharp corners and shall be uniform in shape and colour. Fly ash shall conform to IS 3812 and lime shall conform to class ‘C’ hydrated lime of IS 712. 6.1.1 Dimensions The brick may be modular or non-modular. Sizes for both types of bricks/tiles shall be as per Table 6.1. While use of modular bricks/tiles is recommended, non-modular (FPS) bricks/tiles can also be used where so specified. Non-modular bricks/tiles of sizes other than the sizes mentioned in Table 6.1 may also be used where specified. TABLE 6.1 Type of Bricks/ Tiles Modular Bricks Modular tile bricks Non-modular tile bricks Non-modular bricks

Nominal Size mm 200 × 100 × 100 mm 200 × 100 × 40 mm 229 × 114 × 44 mm 229 × 114 × 70 mm 209

Actual Size mm 190 × 90 × 90 mm 190 × 90 × 40 mm 225 × 111 × 44 mm 225 × 111 × 70 mm SUB HEAD 6.0 : BRICK WORK

6.1.2 Classification Bricks/Brick tiles shall be classified on the basis of their minimum compressive strength as given below : TABLE 6.2 Class Designation 12.5 (125) 10 (100) 7.5 (75) 5 (50) 3.5 (35)

Average compressive strength Not less than Less than 2 2 2 N/mm (kgf/cm ) N/mm (Kgf/cm2) 12.5 (125) 15.0 150 10 (100) 12.5 125 7.5 (75) 10 100 5 (50) 7.5 75 3.5 (35) 5.0 50

The bricks shall have smooth rectangular faces with sharp corner and shall be uniform in colour and emit clear ringing sound when struck. (Note: Upper limits specified in Table 6.2 are for calculating the average compressive strength in accordance with Appendix B of Chapter 6). 6.1.3 Sampling and Tests Samples of bricks shall be subjected to the following tests : (a) Dimensional tolerance. (b) Water absorption. (c) Efflorescence. (d) Compressive strength. 6.1.3.1 Sampling: For carrying out compressive strength, water absorption, efflorescence and dimensional tests, the samples of bricks shall be taken at random according to the size of lot as given in Table 6.3 below. The sample thus taken shall be stored in a dry place until tests are made. For the purpose of sampling, the following definition shall apply. (a) Lot: A collection of bricks of same class and size, manufactured under relatively similar conditions of production. For the purpose of sampling a lot shall contain a maximum, of 50,000 bricks. In case a consignment has bricks more than 50,000 of the same classification and size and manufactured under relatively similar conditions of production, it shall be divided into lots of 50,000 bricks or part thereof. (b) Sample: A collection of bricks selected for inspection and/or testing from a lot to reach the decision regarding the acceptance or rejection of the lot. (c) Defective: A brick failing to meet one or more of the specified requirements. 6.1.3.2 The samples shall be taken as below: (i) Sampling from a Stack: When it is necessary to take a sample from a stack, the stack shall be divided into a number of real or imaginary sections and the required number of bricks drawn from each section. For this purpose bricks in the upper layers of the stack shall be removed to enable units to be sampled from places within the stack. Note: For other methods of sampling i.e. sampling in motion and sampling from lorries or trucks, IS :5454 may be referred. Scale of sampling and criteria for conformity for visual and dimensional characteristics:— Visual characteristics: The bricks shall be selected and inspected for ascertaining their conformity to the requirements of the relevant specification. CPWD SPECIFICATIONS 2009

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The number of bricks to be selected from a lot shall depend on the size of lot and shall be in accordance of Col. 1 and 2 of Table 6.3 for visual characteristics in all cases and dimensional characteristics if specified for individual bricks. (ii) Visual Characteristics: All the bricks selected above in accordance with Col. 1 and 2 of Table 6.3 shall be examined for visual characteristics. If the number of defective bricks found in the sample is less than or equal to the corresponding number as specified in Col. 3 of Table 6.3 the lot shall be considered as satisfying the requirements of visual characteristics, otherwise the lot shall be deemed as not having met the visual requirements. (iii) Dimensional Characteristics: The number of bricks to be selected for inspecting the dimensions and tolerance shall be in accordance with Col. 1 and 4 of Table 6.3. These bricks will be divided into groups of 20 bricks at random and each of the group of 20 bricks thus formed will be tested for all the dimensions and tolerances. A lot shall be considered having found meeting the requirements of dimensions and tolerance if none of the groups of bricks inspected fails to meet the specified requirements. TABLE 6.3 Scale of Sampling and Permissible Number of Defectives for Visual and Dimensional Characteristics No. of bricks in the lot

(1) 2001—10000 10001—35000 35001—50000

For characteristics specified for individual bricks No. of Permissible bricks to be no. of defective selected in the sample (2) (3) 20 1 32 2 50 3

For dimensional characteristics for group of 20 bricks No. of bricks to be selected (4) 40 60 80

Note: In case the lot contains 2000 or less bricks the sampling shall be as per decision of the Engineer-in-Charge. (iv) Scale of Sampling and Criteria for Physical Characteristics: The lot which has been found satisfactory in respect of visual and dimensional requirements shall be next tested for physical characteristics like compressive strength, water absorption, efflorescence as specified in relevant material specification. The bricks for this purpose shall be taken at random from those already selected above. The number of bricks to be selected for each of these characteristics shall be in accordance with relevant columns of Table 6.4. TABLE 6.4 Scale of Sampling for Physical Characteristics Lot size

Sample size for compressive strength, water absorption and efflorescence (1) (2) 2001—10000 5 10001—35000 10 35001—50000 15

Permissible No. of defectives for efflorescence (3) 0 0 1

Warpage Sample Permissible Size No of defects (4) (5) 10 0 20 1 30 2

Note: In case the lot contains 2000 or less bricks, the sampling shall be as per decision of Engineer-in-Charge. 211

SUB HEAD 6.0 : BRICK WORK

(v) A lot shall be considered having satisfied the requirements of physical characteristics if the condition stipulated here in are all satisfied. (a) From the test results for compressive strength, the average shall be calculated and shall satisfy the requirements specified in relevant material specification. Note: In case any of the test results for compressive strength exceeds the upper limit for the class of bricks, the same shall be limited to the upper limit of the class for the purpose of averaging. (b) Wherever specified in the material specification, the compressive strength of any individual bricks tested in the sample shall not fall below the minimum average compressive strength specified for the corresponding class of brick by more than 20 per cent. (c) From the test results for water absorption, the average for the bricks in the sample shall be calculated and shall satisfy the relevant requirements specification in material specification. (d) The number of bricks failing to satisfy the requirements of the efflorescence specified in the relevant specification should not be more than the permissible no. of defectives given in Col. 3 of Table 6.4. 6.1.3.3 Dimensional Tolerances: The dimensions of, modular bricks when tested as described above as per procedure described in Appendix A of Chapter 6 shall be within the following limits per 20 bricks or locally available size as approved by Engineer-in-charge. (a) For modular size Length 7320 to 3880 mm (3800 ± 80 mm) Width 1760 to 1840 mm (1800 ± 40 mm) Height 1760 to 1840 mm (1800 ± 40 mm) for 90 mm high bricks 760 to 840 mm (800 ± 40 mm) for 40 mm high bricks (b) For non modular bricks Length 4520 to 4680 mm (4600 ± 80 mm) Width 2240 to 2160 mm (2200 ± 40 cm) Height 1440 to 1360 mm (1400 ± 40 mm) for 70 mm high bricks 640 to 560 mm (600 ± 40 mm) for 30 mm high bricks Brick Tiles 760 to 840 mm (800 ± 40 mm) for 40 mm high brick tiles In case of non-modular bricks, % age tolerance will be ± 2% for group of 20 numbers of class 10 bricks, and ± 4% for other class of bricks. 6.1.3.4 Compressive Strength: The bricks, when tested in accordance with the procedure laid down in Appendix B of Chapter 6 shall have a minimum average compressive strength for various classes as given in Table 6.2. The compressive strength of any individual brick tested shall not fall below the min. average compressive strength specified for the corresponding class of brick by more than 20%. In case compressive strength of any individual brick tested exceeds the upper limit specified in Table 6.2 for the corresponding class of bricks, the same shall be limited to upper limit of the class as specified in Table 6.2 for the purpose of calculating the average compressive strength. 6.1.3.5 Water Absorption: The average water absorption of bricks when tested in accordance with the procedure laid down in Appendix C of Chapter 6 shall be not more than 20% by weight. 6.1.3.6 Efflorescence: The rating of efflorescence of bricks when tested in accordance with the procedure laid down in Appendix D of Chapter 6 shall be not more than moderate. 6.1.4 Sewer Bricks 6.1.4.1 Sewer bricks are intended for the lining of walls, roofs and floors of sewers used for ordinary sanitary (domestic) sewage. The general practice in the country is also to utilize common building bricks CPWD SPECIFICATIONS 2009

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in the construction of sewers which is not satisfactory. However, these sewer bricks may not be suitable for sewers dealing with industrial effluent (sewage) for which the use of acid resistant bricks in accordance with IS 4860 may be considered. Sewer bricks shall conform to IS 4885. 6.1.4.2 Dimensions and Tolerances Dimensions: The standard sizes of the sewer bricks shall be as follows: Length mm 190 190

Width mm 90 90

Height mm 90 40

For sewers of special shapes, such as the oval sewers, the bricks may have to be suitable tapered to conform to the radii of curvature of the arches and barrels and sides of sewers. Tolerance: The permissible tolerance on the dimensions specified in 6.1.4.2 shall be as follows : Dimensions

Total tolerance for 20 bricks mm + 80 + 40 + 40

mm 190 90 40

6.1.4.3 Compressive Strength: The average compressive strength obtained on a sample of sewer bricks when tested in accordance with the procedure laid down in IS 3495 (Part I) shall be not less than 17.5 N/mm2 (175 kgf/cm2 approximately) and the individual strength of any brick shall be not less than 16 N/mm2 (160 kgf/cm2 approximately). 6.1.4.4 Water Absorption: The average value of water absorption for five bricks after 24 h cold water immersion test when tested in accordance with IS 3495 (Part 2) shall not exceed 10 per cent of the average dry weight of the brick and the absorption for any individual brick shall not exceed 12 per cent. 6.1.4.5 Efflorescence: When the bricks are tested in accordance with the method laid down in IS 3495 (Part 3), the rating of efflorescence shall not be more than ‘slight’. 6.1.5 Burnt Clay Perforated Building Bricks 6.1.5.1 General Quality: The bricks shall be made of suitable clay and shall be thoroughly burnt at the maturing temperature of clay. They shall be free from cracks, flaws and nodules of free lime. They shall have rectangular face with sharp straight edge at right angle. They shall be of uniform colour and texture. These bricks generally should conform to IS 2222. 6.1.5.2 Dimensions and Tolerances: The standard size of burnt clay perforated bricks shall be as follows: Length Width Height (L) (W) (H) mm mm mm Modular Non Modular

190 230

90 110

213

90 70

SUB HEAD 6.0 : BRICK WORK

The permissible tolerances on the dimensions shall be as follows: Dimension mm

Tolerance mm

70, 90 110, 190 230

+4 +7 + 10

Note: The tolerances specified above shall apply to measurements on individual bricks. 6.1.5.3 Perforations: The area of perforation shall be between 30% and 45% of the total area of the corresponding face of the bricks. The perforation shall be uniformly distributed over the surface. In the case of rectangular perforations, the larger dimension shall be parallel to the longer side of the brick. The shorter side of the perforation shall be less than 20 mm incase of rectangular perforations and less than 25 mm diameter in case of circular perforations. The area of each perforation shall not exceed 500 mm2. The thickness of any shell shall not be less then 15 mm and that of any web not less than 10 mm. 6.1.5.4 Compressive Strength: The bricks when tested in accordance with the procedure laid down in IS 3495 (Parts 1 to 4) shall have a minimum average compressive strength of 7 N/ mm2 on net area. The compressive strength of any individual brick tested shall not fall below the minimum compressive strength specified for the corresponding class of bricks. The lot shall then be checked for next lower class of brick. 6.1.5.5 Water Absorption: The bricks when tested in accordance with the procedure laid down in IS 3495 (parts 1 to 4): after immersion in cold water for 24 hours water absorption shall not be more than 20 percent by weight. 6.1.5.6 Efflorescence: The bricks when tested in accordance with the procedure laid down in IS 3495 (Parts 1 to 4) shall have a rating of efflorescence not more than ‘slight’. 6.1.5.7 Warpage: The bricks when tested in accordance with the procedure laid down in IS 3495 (parts 1 to 4) the average warpage shall not exceed 3%. 6.2 BRICK WORK 6.2.1 Classification The brick work shall be classified according to the class designation of bricks used. 6.2.2 Mortar The mortar for the brick work shall be as specified, and conform to accepted standards. Lime shall not be used where reinforcement is provided in brick work. 6.2.3 Soaking of Bricks Bricks shall be soaked in water before use for a period for the water to just penetrate the whole depth of the bricks. Alternatively bricks may be adequately soaked in stacks by profusely spraying with clean water at regular intervals for a period not less than six hours. The bricks required for masonry work CPWD SPECIFICATIONS 2009

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using mud mortar shall not be soaked. When the bricks are soaked they shall be removed from the tank sufficiently early so that at the time of laying they are skin-dry. Such soaked bricks shall be stacked on a clean place where they are not again spoiled by dirt earth etc. Note I: The period of soaking may be easily found at site by a field test in which the bricks are soaked in water for different periods and then broken to find the extent of water penetration. The least period that corresponds to complete soaking will be the one to be allowed for in construction work. Note II : If the bricks are soaked for the required time in water that is frequently changed the soluble salt in the bricks will be leached out, and subsequently efflorescence will be reduced. 6.2.4 Laying 6.2.4.1 Bricks shall be laid in English Bond (Fig. 6.2, 6.3, 6.4) unless otherwise specified. For brick work in half brick wall, bricks shall be laid in stretcher bond. Half or cut bricks shall not be used except as closer where necessary to complete the bond. Closers in such cases, shall be cut to the required size and used near the ends of the wall. Header bond shall be used preferably in all courses in curved plan for ensuring better alignment. Note: Header bond shall also be used in foundation footings unless thickness of walls (width of footing) makes the use of headers impracticable. Where thickness of footing is uniform for a number of courses, the top course of footing shall be headers. 6.2.4.2 All loose materials, dirt and set lumps of mortar which may be lying over the surface on which brick work is to be freshly started, shall be removed with a wire brush and surface wetted. Bricks shall be laid on a full bed of mortar, when laying, each brick shall, be properly bedded and set in position by gently pressing with the handle of a trowel. Its inside face shall be buttered with mortar before the next brick is laid and pressed against it. Joints shall be fully filled and packed with mortar such that no hollow space are left inside the joints. 6.2.4.3 The walls shall be taken up truly in plumb or true to the required batter where specified. All courses shall be laid truly horizontal and all vertical joints shall be truly vertical. Vertical joints in the alternate course shall come directly one over the other. Quoin, Jambs and other angles shall be properly plumbed as the work proceeds. Care shall be taken to keep the perpends properly aligned within following maximum permissible tolerances : (a) Deviation from vertical within a storey shall not exceed 6 mm per 3 m height. (b) Deviation in verticality in total height of any wall of building more than one storey in height shall not exceed 12.5 mm. (c) Deviation from position shown on plan of any brick work shall not exceed 12.5 mm. (d) Relative displacement between load bearing wall in adjacent storeys intended to be vertical alignments shall not exceed 6 mm. (e) A set of tools comprising of wooden straight edge, masonic spirit levels, square, 1 metre rule line and plumb shall be kept on the site of work for every 3 masons for proper check during the progress of work. 6.2.4.4 All quoins shall be accurately constructed and the height of brick courses shall be kept uniform. This will be checked using graduated wooden straight edge or storey rod indicating height of each course including thickness of joints. The position of damp proof course, window sills, bottom of lintels, top of the wall etc. along the height of the wall shall be marked on the graduated straight edge or storey rod. Acute and obtuse quoins shall be bonded, where practicable in the same way as square quoins. Obtuse quoins shall be formed with squint showing three quarters brick on one face and quarter brick on the other.

215

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6.2.4.5 The brick work shall be built in uniform layers. No part of the wall during its construction shall rise more than one metre above the general construction level. Parts of wall left at different levels shall be raked back at an angle of 45 degrees or less with the horizontal. Toothing shall not be permitted as an alternative to raking back. For half brick partition to be keyed into main walls, indents shall be left in the main walls. 6.2.4.6 All pipe fittings and specials, spouts, hold fasts and other fixtures which are required to be built into the walls shall be embedded, as specified, in their correct position as the work proceeds unless otherwise directed by the Engineer-in-Charge. 6.2.4.7 Top courses of all plinths, parapets, steps and top of walls below floor and roof slabs shall be laid with brick on edge, unless specified otherwise. Brick on edge laid in the top courses at corner of walls shall be properly radiated and keyed into position to form cut (maru) corners as shown in Fig 6.4. Where bricks cannot be cut to the required shape to form cut (maru) corners, cement concrete 1:2:4 (1 cement : 2 coarse sand : 4 graded stone aggregate 20 mm nominal size) equal to thickness of course shall be provided in lieu of cut bricks. 6.2.4.8 Bricks shall be laid with frog (where provided) up. However, when top course is exposed, bricks shall be laid with frog down. For the bricks to be laid with frog down, the frog shall be filled with mortar before placing the brick in position. 6.2.4.9 In case of walls one brick thick and under, one face shall be kept even and in proper plane, while the other face may be slightly rough. In case of walls more than one brick thick, both the faces shall be kept even and in proper plane. 6.2.4.10 To facilitate taking service lines later without excessive cutting of completed work, sleeves (to be paid separately) shall be provided, where specified, while raising the brick work. Such sleeves in external walls shall be sloped down outward so as to avoid passage of water inside. 6.2.4.11 Top of the brickwork in coping and sills in external walls shall be slightly tilted. Where brick coping and sills are projecting beyond the face of the wall, drip course/throating (to be paid separately) shall be provided where indicated. 6.2.4.12 Care shall be taken during construction that edges of jambs, sills and projections are not damaged in case of rain. New built work shall be covered with gunny bags or tarpoulin so as to prevent the mortar from being washed away. Damage, if any, shall be made good to the satisfaction of the Engineer-in-Charge. 6.2.4.13 Vertical reinforcement in the form of bars (MS or high strength deformed bars or thermomechanically treated bars as per direction of Engineer-in-Charge)), considered necessary at the corners and junction of walls and jamb opening doors, windows etc. shall be encased with cement mortar not leaner than 1:4 (1 cement : 4 coarse sand), or cement concrete mix as specified. The reinforcement shall be suitably tied, properly embedded in the foundation and at roof level. The dia. of bars shall not be less than 8 mm and concrete grade shall be minimum 1:3:6 (1 cement : 3 coarse sand : 6 graded stone aggregate 20 mm nominal size). 6.2.4.14 In retaining walls and the like, where water is likely to accumulate, weep holes, 50 to 75 mm square shall be provided at 2 m vertically and horizontally unless otherwise specified. The lowest weep hole shall be at about 30 cm above the ground level. All weep holes shall be surrounded by loose stones and shall have sufficient fall to drain out the water quickly. Note : Work of providing loose stone will be payable extra.

CPWD SPECIFICATIONS 2009

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6.2.4.15 Work of cutting chases, wherever required to be made in the walls for housing G.I. pipe, CI pipe or any other fixtures shall be carried out in various locations as per guidelines given below : (a) Cutting of chases in one brick thick and above load bearing walls. (i) As far as possible services should be planned with the help of vertical chases. Horizontal chases should be avoided. (ii) The depths of vertical chases and horizontal chases shall not exceed one-third and one-sixth of the thickness of the masonry respectively. (iii) When narrow stretches of masonry (or short length of walls) such as between doors and windows, cannot be avoided they should not be pierced with openings for soil pipes or waste pipes or timber joints, etc. Where there is a possibility of load concentration such narrow lengths of walls shall be checked for stresses and high strength bricks in mortar or concrete walls provided, if required. (iv) Horizontal chases when unavoidable should be located in the upper or lower one-third of height of storey and not more than three chases should be permitted in any stretch of a wall. No continuous horizontal chase shall exceed one metre in length. Where unavoidable, stresses in the affected area should be checked and kept within the permissible limits. (v) Vertical chases should not be closer than 2 m in any stretch of a wall. These shall be kept away from bearings of beams and lintels. If unavoidable, stresses in the affected area should be checked and kept within permissible limits. (vi) Masonry directly above a recess, if wider than 30 cm horizontal dimension) should be supported on lintel. Holes in masonry may be provided upto 30 cm width and 30 cm height without any lintel. In the case of circular holes in the masonry, no lintel need be provided for holes upto 40 cm in diameter. (b) Cutting of chases in half brick load bearing walls. No chase shall be permitted in half brick load bearing walls and as such no reccessed conduits and concealed pipes shall be provided with half brick thick load bearing walls. (c) Cutting of chases in half brick non-load bearing wall : Services should be planned with the help of vertical chases. Horizontal chase should be provided only when unavoidable. 6.2.5 Joints The thickness of all types of joints including brick wall joints and cross joints shall be such that four course and three joints taken consecutively shall measure as follows: (i) In case of modular bricks conforming to IS 1077 specification for common burnt clay buildings bricks, equal to 39 cm. (ii) In case of non-modular bricks, it shall be equal to 31 cm. Note : Specified thickness of joints shall be of 1 cm. Deviation from the specified thickness of all joints shall not exceed one-fifth of specified thickness. 6.2.5.1 Finishing of Joints: The face of brick work may be finished flush or by pointing. In flush finishing either the face joints of the mortar shall be worked out while still green to give a finished surface flush with the face of the brick work or the joints shall be squarely raked out to a depth of 1 cm while the mortar is still green for subsequently plastering. The faces of brick work shall be cleaned with wire brush so as to remove any splashes of mortar during the course of raising the brick work. In pointing, the joints shall be squarely raked out to a depth of 1.5 cm while the mortar is still green and raked joints shall be brushed to remove dust and loose particles and well wetted, and shall be later refilled with mortar to give ruled finish. Some such finishes are ‘flush’, ‘weathered’, ruled, etc. 6.2.6 Curing The brick work shall be constantly kept moist on all faces for a minimum period of seven days. Brick work done during the day shall be suitably marked indicating the date on which the work is done so as to keep a watch on the curing period.

217

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6.2.7 Scaffolding Scaffolding shall be strong to withstand all dead, live and impact loads which are likely to come on them. Scaffolding shall be provided to allow easy approach to every part of the work. 6.2.7.1 Single Scaffolding: Where plastering, pointing or any other finishing has been indicated for brick work, single scaffolding may be provided, unless otherwise specified. In single scaffolding, one end of the put-logs/pole shall rest in the hole provided in the header course of brick masonry. Not more than one header for each put-log/pole shall be left out. Such holes shall not be allowed in the case of pillars, brick work less than one metre in length between the openings or near the skew backs of arches or immediately under or near the structural member supported by the walls. The holes for putlogs/poles shall be made good with brick work and wall finishing as specified. 6.2.7.2 Double Scaffolding: Where the brick work or tile work is to be exposed and not to be finished with plastering etc. double scaffolding having two independent supports, clear of the work, shall be provided. 6.2.8 Measurements 6.2.8.1 Brick work shall be measured in cubic metres unless otherwise specified. Any extra work over the specified dimensions shall be ignored. Dimensions shall be measured correct to the nearest 0.01 m i.e. 1 cm. Areas shall be calculated to the nearest 0.01 sq mtrs and the cubic contents shall be worked out to the nearest 0.01 cubic metres. 6.2.8.2 Brick work shall be measured separately in the following stages: (a) From foundation to floor one level (Plinth level) (b) Plinth (floor one) level to floor two level (c) Between two specified floor levels above floor two level Note : (i) Brick work in parapet walls, mumty, lift machine room and water tanks constructed on the roof upto 1.2 m height above roof shall be measured together with the corresponding work of the floor next below. 6.2.8.3 No deductions or additions shall be done and no extra payment made for the following : Note : Where minimum area is defined for deduction of an opening, void or both, such areas shall refer only to opening or void within the space measured. (a) Ends of dissimilar materials (that is, joists, beams, lintels, posts, girders, rafters, purlins, trusses, corbels, steps, etc.); up to 0.1 m2 in section; (b) Opening up to 0.1 m2 in area (see Note); (c) Wall plates, bed plates, and bearing of slabs, chajjas and the like, where thickness does not exceed 10 cm and bearing does not extend over the full thickness of wall; (d) Cement concrete blocks as for hold fasts and holding down bolts; (e) Iron fixtures, such as wall ties, pipes upto 300 mm diameter and hold fasts for doors and windows; and (f) Chases of section not exceeding 50 cm in girth. (g) Bearing portion of drip course, bearing of moulding and cornice. Note : In calculating area of an opening, any separate lintel or sills shall be included with the size of the opening but end portions of lintel shall be excluded. Extra width of rebated reveals, if any, shall also be excluded. 6.2.8.4 Walls half brick thick and less shall each be measured separately in square metres stating thickness.

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6.2.8.5 Walls beyond half brick thickness shall be measured in multiples of half brick which shall be deemed to be inclusive of mortar joints. For the sizes of bricks specified in 6.1.1, half brick thickness shall mean 100 mm for modular and 115 mm for non-modular bricks. Where fractions of half brick occur due to architectural or other reasons, measurement shall be as follows : (a) upto 1/4th brick-actual measurements and (b) exceeding 1/4 brick-full half bricks. 6.2.8.6 String courses, projecting pilasters, aprons, sills and other projections shall be fully described and measured separately in running metres stating dimensions of each projection. 6.2.8.7 Square or rectangular pillars shall be measured separately in cubic metres in multiple of half brick. 6.2.8.8 Circular pillars shall be measured separately in cubic metres as per actual dimensions. 6.2.8.9 Brick work curved on plan shall be measured like the brick work in straight walls and shall include all cutting and wastage of bricks, tapered vertical joints and use of extra mortar, if any. Brick work curved on plan to a mean radius not exceeding six metres shall be measured separately and extra shall be payable over the rates for brick work in straight walls. Nothing extra shall be payable if the mean radius of the brick work curved in plan exceeds six metres. 6.2.8.10 Tapered walls shall be measured net as walls and extra payment shall be allowed for making tapered surface for brick work in walls. 6.2.8.11 Brick work with brick tiles shall be measured and paid for separately. 6.2.9 Rate The rate shall include the cost of materials and labour required for all the operations described above except the vertical reinforcement and its encasement in cement mortar or cement concrete. The rate shall also include the following : (a) Raking out joints or finishing joints flush as the work proceeds; (b) Preparing tops of existing walls and the like for raising further new brick work. (c) Rough cutting and waste for forming gables, splays at eaves and the like. (d) Leaving holes for pipes upto 150 mm dia. and encasing hold fasts etc. (e) Rough cutting and waste for brick work curved in plan and for backing to stone or other types of facing. (f) Embedding in ends of beams, joists, slabs, lintels, sills, trusses etc. (g) Bedding wall plates, lintels, sills, roof tiles, corrugated sheets, etc. in or on walls if not covered in respective items and (h) Leaving chases of section not exceeding 50 cm in girth or 350 sq cm in cross-section. (i) Brick on edge courses, cut brick corners, splays reveals, cavity walls, brick works curved on plan to a mean radius exceeding six metres. 6.3 BRICK WORK IN ARCHES (FIG. 6.5) 6.3.0 The detailed specifications for brick work mentioned in 6.2 shall apply, in so far as these are applicable. Arch work shall include masonry for both gauged as well as plain arches. In gauged arches, cut or moulded bricks shall be used. In plain arches, uncut bricks shall be used. Brick forming skew-backs shall be dressed or cut so as to give proper radial bearing to the end voussiors. Defects in dressing of bricks shall not be covered by extravagant use of mortar, nor shall the use of chips or bats etc. be permitted. 219

SUB HEAD 6.0 : BRICK WORK

The bricks of the spandrel wall at their junctions with the extrudes of the arch shall be cut to fit the curvature of the arch. 6.3.1 Circular Arches These shall be either (a) plain arches, and shall be built in half brick concentric rings with break joints, or (b) gauged arches built with bricks cut or moulded to proper shape. The arch work shall be carried up from both ends simultaneously and keyed in the centre. The bricks shall be flush with mortar and well pressed into their positions so as to squeeze out a part of their mortar and leave the joints thin and compact. All joints shall be full of mortar and thickness of joints shall not be less than 5 mm nor more than 15 mm. After the arch is completed, the haunches shall be loaded by filling up the spandrels upto the crown level of the arch. Care shall be taken to load the haunches on two sides of the spandrels. When the arch face is to be pointed (and not plastered), the face bricks shall be cut to proper shape or moulded, so as to have the joints not more than 5 mm thick. These shall be laid with radial joints to the full depth of the arch. The voussoirs shall break joints to the full depth of the arch. 6.3.2 Flat Arches These shall be gauged arches of brick cut or moulded to proper shape. The extrados shall be kept horizontal and the intrados shall be given slight camber of 1 in 100 of the span. The centre of the arch from which joints shall radiate, shall be determined by the point of the inter-section of the two lines drawn from the ends of the arch at the springing level and at 60° to horizontal. In flat arches, bricks shall be laid with radial joints to the full depth of arch and voussoirs breaking joints with each other. The arch work shall be carried up from both ends simultaneously and keyed in the centre. The thickness of the joints shall not exceed 5 mm. Flat arches may be used for the sake of appearance but for purpose of carrying loads of the wall above, these shall be used in conjunction with relieving arches, lintels placed below. 6.3.3 Centring and Shuttering The centring and shuttering for the arch shall be got approved by the Engineer-in-Charge before the arch work is started. It shall be strong enough to bear the dead load of the arch and the live loads that are likely to come upon it during construction, without any appreciable deflections. The shuttering shall be tightened with hard wood wedged or sand boxes, so that the same could be eased without jerks being transmitted to the arch. The sequence of easing the shuttering shall be got approved from the Engineer-in-Charge. The shuttering shall be struck within 48 hours of the completion of the arch but not before 24 hours. This shall be done after the spandrel has been filled in and the arch loaded. 6.3.4 Measurements The length of the arch shall be measured as the mean of the extrados and intrados of the arch correct to a cm. The thickness of the arch shall be measured in multiples of the half brick. The breadth in the direction of the thickness of wall shall be measured as specified. The cubical contents shall be calculated in cubic metre, correct to two places of decimal. For arches exceeding 6 m in spans extra payment shall be made on the actual area of the soffit for additional cost of centring including all strutting, bolting, wedging, easing, striking and its removal. 6.3.5 Rate The rate is inclusive of the cost of the materials and labour required for all the operations described above. CPWD SPECIFICATIONS 2009

220

6.4 HALF BRICK WORK Brick work in half brick walls shall be done in the same manner as described above in 6.2.4 except that the bricks shall be laid in stretcher bond. When the half brick work is to be reinforced, 2 Nos. M.S. bars of 6 mm dia., shall be embedded in every third course as given in the item (the dia of bars shall not exceed 8 mm). These shall be securely anchored at their end where the partitions end. The free ends of the reinforcement shall be keyed into the mortar of the main brick work to which the half brick work is joined. The mortar used for reinforced brick work shall be rich dense cement mortar of mix 1:4 (1 cement: 4 coarse sand). Lime mortar shall not be used. Over laps in reinforcement, if any shall not be less than 30 cm. The mortar interposed between the reinforcement bars and the brick shall not be less than 5 mm. The mortar covering in the direction of joints shall not be less than 15 mm. 6.4.1 Measurements The length and height of the wall shall be measured correct to a cm. The area shall be calculated in sq.m. where half brick wall is joined to the main walls of one brick or greater thickness and measurements for half brick wall shall be taken for its clear length from the face of the thicker wall. 6.4.2 Rate The rate includes the cost of the materials and labour involved in all the operations described above except reinforcement which is to be paid for separately. 6.5 BRICK TILE WORK 6.5.0 The work shall be done in the same manner as described in 6.2.4 except that brick tile shall be used instead of bricks. The measurement and rate shall be same as specified under 6.2. 6.6 HONEY COMB BRICK WORK The honeycomb brick work shall be done with specified class of brick, laid in specified mortar. All joints and edges shall be struck flush to give an even surface. The thickness of the brick honeycomb work shall be half-brick only, unless otherwise specified. Openings shall be equal and alternate with half brick laid with a bearing of 2 cm on either side. 6.6.1 Measurements The length and height shall be measured correct to a cm. Area shall be calculated in square metres correct to two places of decimal. Honeycomb openings shall not be deducted. 6.6.2 Rate The rate includes the cost of materials and labour involved in all the operations described above. 6.7 JOINING OLD BRICK WORK WITH NEW BRICK WORK 6.7.1 In case the height of the bricks of old as well as new work is same, the old work shall be toothed to the full width of the new wall and to the depth of a quarter of brick in alternate courses. In case the height of the bricks is unequal, then the height of each course of new work shall be made equal to the height of the old work by adjusting thickness of horizontal mortar joints in the new wall. Where necessary, adjustment shall be made equal to thickness of old wall by adjusting the thickness of vertical joints. 6.7.2 For joining new cross wall to old main walls, a number of rectangular recesses of width equal to the thickness of cross wall, three courses in height and half a brick in depth shall be cut in the main

221

SUB HEAD 6.0 : BRICK WORK

walls. A space of the three courses shall be left between two consecutive recesses. The new cross wall shall be bonded into the recesses to avoid any settlement. 6.7.3 Joining of old brick work with the new brick work shall be done in such a way that there shall not be any hump or projection at the joint. 6.7.4 Measurement The height and thickness of vertical face in contact with new work shall be measured to the nearest 0.01 m and the area shall be calculated to the nearest 0.01 sqm. 6.7.5 Rate The rate includes the cost of labour and material involved in all the operations described above. 6.8 MOULDING AND CORNICES 6.8.0 The specifications described under 6.2 shall apply in so far these are applicable. Mouldings and cornices shall be made with bricks as specified for brick work. The bricks shall be cut and dressed to the required shape as shown in the architectural drawings. 6.8.1 Cornices shall not ordinarily project by more than 15 cm to 20 cm and this projection shall be obtained by projecting each brick course by more than one fourth of the length. For cornices projecting more than 20 cm and requiring more than quarter bricks projection, metal cramps shall be used and paid for separately. 6.8.2 Corbelling shall be brought roughly to shape by plastering with the specified mortar. When the mortar is still green, the mouldings shall be finished straight and true with the help of metal templates. 6.8.3 Curing and Protection The mouldings and cornices shall be cured for at least seven days. These shall be protected from the effects of sun and rain by suitable covering and also from damage during the execution of the work. 6.8.4 Measurements For the purpose of measurements, the sectional periphery of mouldings and cornices (excluding the portion in contact with wall) shall be measured in centimetres and length in metres (fig. below). The girth and length shall be measured correct to a cm. No deduction shall be made from the masonry of wall for the bearing of the moulding and cornices.

Note : 1 The sectional periphery curve ABCDEF. 2. Length FA shall not be measured. CPWD SPECIFICATIONS 2009

222

6.8.5 Rate The rate includes the cost of materials and labour involved in all the operations described above. 6.9 BRICK WORK UNDER WATER OR FOUL CONDITIONS Brick Work under following conditions : (i) Work in or under water/or liquid mud; (ii) Work in or under foul positions Shall be measured separately for payment of extra rate over and above the quantity measured and paid under para 6.2.8. 6.10 EXPOSED BRICK WORK 6.10.1 Facing Bricks The facing bricks made from suitable soils shall be free from cracks, flaws, nodules of free lime warpage and organic matter. These shall be thoroughly burnt and shall have plane rectangular faces with parallel sides and sharp straight right angled edges. Facing bricks shall have uniform colour and even texture. Unless otherwise specified, facing bricks shall be machine moulded only. As far as possible, total requirement of facing bricks for a work shall be arranged from the same kiln. Bricks with chipped edges and broken corners shall not be used. 6.10.2 Dimensions and Tolerances The standard sizes of machine moulded facing bricks shall be as specified in 6.1.1. 6.10.2.1 The permissible tolerances shall be as under: Dimension

Length Width Thickness

Tolerance (For Machine moulded bricks) mm +3 + 1.5 + 1.5

mm 190 or 225 90 or 111 40 or 44

Note: Tolerance and Dimensions for selected hand moulded bricks + 4 mm in length and + 3 mm in width and thickness). 6.10.3 Sampling As per Para 6.1.3 and 6.1.3.2. 6.10.4 Physical Requirements Facing bricks shall be of class designation 75 unless otherwise specified. Average compressive strength shall not be less than 7.5 N/mm2, water absorption shall not exceed 20 per cent by weight and efflorescence rating shall be nil when tested in accordance with the procedure laid down and tolerance in dimensions shall be checked as per the procedure laid down in Appendix A-2. Mortar, Soaking of Bricks and laying shall be as specified in Para 6.2.2, 6.2.3 and 6.2.4 respectively. 6.10.5 Joints in the exposed brick work shall be truly horizontal and vertical and kept uniform with the help of wooden or steel strips. The thickness of joints shall be as per 6.2.5. 6.10.6 Curing and scaffolding shall be as specified in 6.2.6 and 6.2.7 to 6.2.7.2 respectively. 6.10.7 Measurements Exposed brick work in face using machine moulded bricks and selected hand moulded bricks shall be measured separately and the measurement shall be as specified in 6.2.8. 223

SUB HEAD 6.0 : BRICK WORK

6.10.8 Rate The rates shall be as specified in 6.2.9 and shall also include the following : (a) Labour for selecting bricks and wastage of bricks where use of selected hand moulded brick is specified. (b) Leaving uniform horizontal and vertical grooves of specified depth and providing joints of required thickness using wooden or steel strips as the work proceeds. 6.11 CAVITY WALL It is a wall comprising of two leaves, each leaf being built of masonry units and separated by a cavity so as to provide an air space within the wall and tied together with metal ties or bonding units to ensure that two leaves act as one structural unit. The width of the cavity shall not be less than 50 mm and not more than 115 mm. Each leaf of the cavity wall shall not be less than 75 mm. The space between the leaves being either left as cavity or filled with non-load bearing insulating and water proofing material. 6.11.1 Metal Ties These may be of galvanised iron, wrought iron, gun metal, brass, copper, stainless steel or any such corrosion resistant metal, made of flats 20 x 5 mm cranked or twisted at their mid point with ends split and fish tailed. The ties shall be built into horizontal bed joints during erection, placed sloping towards the exterior side to prevent water from flowing along it from outer to inner leaf side (For details refer Fig. 6.6 of Chapter 6). 6.11.2 Bonding Units These shall be preferably precast R.C.C. units having cross-section as per Fig. No. 6.6. Length of the Bonding units will be sum of thickness of both leaves plus width of cavity if the leaves are 75 mm or 115 mm. If the leaves are more than 115 mm thick, then the length of a unit will be 2 × 115 + width of cavity as shown in Fig. 6 of Chapter 6. Precast RCC units shall be provided with 2 no., 6 mm mild steel reinforcement bars tied with 2 no. 3 mm. dia. M.S. wire/hard drawn wire cross bars (As shown in Fig. 6 of Chapter 6) placed in the centre of units. Cement concrete used in the bonding units shall not be leaner than 1:3:6 (1 cement : 3 coarse sand : 6 graded stone aggregate 20 mm nominal size). 6.11.3 Spacing Metal ties/bonding units shall be spaced not more than 90 cm apart horizontally and 45 cm vertically and staggered in each course. Additional ties shall be used near openings. 6.11.4 Restrictions Cavity walls shall not normally be built more than 7.5 metres in height and 9 metres in length. Where large lengths and heights are desired, the wall shall be divided into panels with strengthening measures such as pillars etc. Cavity shall be covered at the top with at least two courses of masonry unit and/or a coping over it. Adoption of cavity walls is not recommended when heavy concentrated load from beam etc. are to be supported by walls. 6.11.5 Measurements and Rate (a) Brick work in cavity walls shall be included and measured with general brick work. The width of the cavity shall not be measured. Skin of cavity wall, half brick thickness shall be measured as and paid as described in para 6.2.8 and 6.4. (b) The forming of the cavity shall be given in square metres stating the width of the cavity and shall include the metal ties/bonding unit specifying the numbers per square metre. (c) Labour and material for closing cavities at the jambs, sills and heads of opening shall be as described and measured separately in running metres. (d) The item shall include use of device for keeping cavity clear and forming the requisite weep and vent holes and nothing extra on this account shall be payable. CPWD SPECIFICATIONS 2009

224

6.12

GYPSUM PARTITION PANELS

6.12.1 The material shall conform to IS:2849. 6.12.2 Dimensions As per the item nomenclature. 6.12.3 Laying (i) Panels are stored in a dry place and water should not come in contact with panels during or after construction. If the panels get wet, they should be dried before use. (ii) The floor should be perfectly level before laying the first course. All panels must be properly aligned to the plumb. Successive layer of panels must be alternatively staggered so that vertical joints are not in the same line. (iii) The recommended quantity of Gypsum Bonding Plaster must be used for joints and filling the grooves made for conduits, pipelines, etc. Excess Bonding Plaster must be scooped and removed, so that the joints and the places where the grooves are filled in are flush and even. (iv) The walls should be dry and sanding done properly especially at joints before the primer is applied so that the surface is even and joints will not be visible after painting. Avoid chasing with chisel and hammer. Use electrical saw or grooving tools for conduiting etc. (v) The recommended span of walls is maximum 6 meters and maximum height is 4.5 meters. (vi) Gypsum panel can easily be cut with coarse tooth hand saw, electric jigsaw, etc. The panels can be cut, sawn, drilled, milled or dowelled on the job. For concealed piping and conduit, the depth of groove should not exceed 50 mm. Hammer and chisel techniques to form chases must be avoided. (vii) Sanding: This application is to make the surface level without undulations. To make the gypsum wall surface level (in particular at joints, where there is excess bonding plaster), do sanding with sand paper at joints and other places, wherever you find uneven surface, otherwise joints will be visible after painting. It is important to sand all joints uniformly. (viii) Primer Application: The purpose of the primer is to give a better adhesion to the paint and also to reduce consumption of paint on the wall. Water thinable primers shall be used only. 6.12.4 Measurements The length and height shall be measured correct to a cm. Area shall be calculated in square meters correct to two place of decimal. No deduction shall be made for ducts, opening made from the standard size of panel. 6.12.5 Rate The rate shall include the cost of materials and labour involved in all the operations described above. 6.13 BRICK EDGING 6.13.1 The edging shall be of bricks of class specified in the item. The specifications of bricks shall be as described in 6.1. Trenches of required depth and width shall first be made along the edge of the plinth protection to receive the bricks for edging. The bed of trenches shall be compacted to a firm and even surface. The brick shall be laid true to line in cement mortar 1:4 (1 cement: 4 fine sand) with length parallel and butting the plinth protection. The top face of the brick edging shall be in one level to conform to the finished level of the plinth protection adjacent to the edging. After the concreting is done, no portion of the brick edging shall project above the adjacent concrete surface. Cement mortar shall conform to the specification described in chapter 3.0. 6.13.2 Measurements The brick edging shall be measured in running metere correct a cm. 6.13.3 Rate Rate shall include the cost of materials and labour involved in all operations.

225

SUB HEAD 6.0 : BRICK WORK

APPENDIX A

TEST FOR DIMENSIONAL TOLERANCE (Clause 6.1.3.3) A -1. Sampling As per para 6.1.3.1 and 6.1.3.2. A -2. Procedure All the blisters, loose particles of clay and small projections shall be removed from the surface of bricks. Each specimen of 20 bricks shall then be arranged upon a level surface successively as indicated in Fig. A, B and C of para A-4 below in contact with each other and in straight line. The overall length of the assembled bricks (20 Nos) shall be measured with a steel tape sufficiently long to measure the whole row at one stretch. A-3. Tolerance The actual dimensions of bricks when tested as described in A-2 shall be within the following limits per 20 bricks. Modular Bricks Length 3720 to 3880 mm (3800 ± 80 mm) Width 1760 to 1840 mm (1800 ± 40 mm) Height 1760 to 1840 mm (1800 ± 40 mm) for 90 mm high brick 760 to 840 mm (800 ± 40 mm) for 40 mm high brick Non-Modular Bricks For class 10 Length (4520 to 4680) mm (4600 ± 80 mm) Width (2240 to 2160) mm (2200 ± 40 mm) Height (1440 to 1360) mm (1400 ± 40 mm) for 70 mm high bricks (640 to 560) mm (600 ± 40 mm) for 30 mm high bricks For other classes Length (4320 to 4680) mm Width (2130 to 2310) mm Height (1340 to 1460) mm for 70 mm high bricks (840 to 920) mm for 44 mm high bricks A-4. Criteria for Conformity A lot shall be considered conforming to the requirements of dimensions and tolerances if all the groups of bricks are tested to meet the specified requirements. 1 to 2 CM 4 CM

'A' Measurement of Length 10 CM

'B' Measurement of Width

'C' Measurement of Height

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APPENDIX B

TEST FOR COMPRESSIVE STRENGTH (Clause 6.1.3.4)

B-1. Specimen Five whole bricks shall be taken from the samples as specimens for this test. Length and width of each specimen shall be measured correct to 1 mm. B-2. Apparatus The apparatus consists of compression testing machine, the compression plate of which shall have a ball seating in the form of portion of a sphere the centre of which shall coincide with the centre of the plate. B-3. Procedure (a) Pre-conditioning: The specimen shall be immersed in the water for 24 hours at 25º to 29ºC. Any surplus moisture shall be allowed to drain at room temperature. The frog of the bricks should be filled flush with mortar 1:3 (1 cement : 3 clean coarse sand of grade 3 mm and down) and shall be kept under damp jute bags for 24 hours, after that these shall be immersed in clean water for three days. After removal from water, the bricks shall be wiped out of any traces of moisture. (b) Actual Testing: Specimen shall be placed with flat faces horizontal and mortar filled face upward between three 3 ply plywood sheets each of thickness 3 mm and carefully centred between plates of the testing machine. Plaster of Paris can also be used in place of plywood sheets to ensure a uniform surface. Load shall be applied carefully axially at uniform rate of 14 N/mm2 per minute till the failure of the specimen occurs. B-4. Reporting the Test Results The compressive strength of each specimen shall be calculated in N/mm2 as under : Maximum load at failure (in N) Compressive Strength = ———————————————— Area of Specimen (in sq mm) In case the compressive strength of any individual brick tested exceeds the upper limit of the average compressive strength specified for the corresponding class of brick, the same shall be limited to the upper limit of the class specified in 6.1.2 for the purpose of calculating the average compressive strength. Compressive strength of all the individual bricks comprising the sample shall be averaged and reported. B-5. Criteria for Conformity A lot shall be considered having satisfied the requirements of average compressive strength if the average compressive strength specified in 6.1.2 for the corresponding class of brick tested is not below the minimum average compressive strength specified for the corresponding class of bricks by more than 20 per cent.

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SUB HEAD 6.0 : BRICK WORK

APPENDIX C

TEST FOR WATER ABSORPTION (Clause 6.1.3.5) C-1. No. of Specimen Five whole bricks shall be taken from samples as specimen for this test. C-2. Apparatus A balance required for this test shall be sensitive to weigh 0.1 percent of the weight of the specimen. C-3. Procedure (a) Pre-conditioning: The specimen shall be allowed to dry in a ventilated oven at a 110°C to 115°C till it attains a substantially constant weight. If the specimen is known to be relatively dry, this would be accomplished in 48 hours, if the specimen is wet, several additional hours may be required to attain a constant weight. It shall be allowed to cool at room temperature. In a ventilated room, properly separated bricks will require four hours for cooling, unless electric fan passes air over them continuously in which case two hours may suffice. The cooled specimen shall be weigh (W1) a warm specimen shall not be used for this purpose. (b) Actual Testing: Specimen shall be completely dried before immersion in the water. It shall be kept in clean water at a temperature of 27°C ± 2°C for 24 hours. Specimen shall be wiped out of the traces of water with a damp cloth after removing from the water and then shall be weighed within three minutes after removing from water (W2). C-4. Reporting the Test Results The water absorption of each specimen shall be calculated as follows and the average of five tests shall be reported.

⎛ W − W1 ⎞ WaterAbsorption = ⎜ 2 ⎟ ×100 ⎝ W1 ⎠ C-5. Criteria for Conformity A lot shall be considered having satisfied the requirements of water absorption if the average water absorption is not more than 20% by weight.

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APPENDIX D

TEST FOR EFFLORESCENCE (Clause 6.1.3.6) D-1. No. of Specimen Five whole bricks shall be taken as specimen for this test. D-2. Apparatus Apparatus required for this test shall be a shallow flat bottom dish containing distilled water. D-3. Procedure (actual testing) The brick shall be placed vertically in the dish with 2.5 cm immersed in the water. The room shall be warm (18ºC to 30ºC) and well ventilated. The bricks should not be removed until it absorbs whole water. When the whole water is absorbed and the brick appears to be dry, place a similar quantity of water in that dish and allow it to evaporate as before. The brick shall be examined after the second evaporation. D-4. Reporting the Test Results The rating to efflorescence in ascending order shall be reported as ‘NIL’, ‘SLIGHT’, ‘MODERATE’, ‘HEAVY’ or ‘SERIOUS’ in accordance with the following :

(a) NIL: When there is no perceptible deposit of efflorescence. (b) SLIGHT: When not more than 10 per cent of the area of the brick is covered with a thin deposit of salts. (c) MODERATE: When there is heavier deposit and covering upto 50% of the area of the brick surface but unaccompanied by powdering or flaking of the surface. (d) HEAVY: When there is a heavy deposit of salts covering 50% or more of the brick surface but unaccompanied by powdering or flaking of the surface. (e) SERIOUS: When there is heavy deposit of salts, accompanied powdering and/or flaking of the surface and tending to increase in the repeated wetting of the specimen. D-5. Criteria for Conformity A lot be considered having satisfied the requirements of efflorescence if for 4 out of the specimen of 5 bricks, the rating of efflorescence is not beyond “Moderate”.

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SUB HEAD 6.0 : BRICK WORK

BRICK WORK Sub Head : Brick Work Clause : 6.0 & 6.2.8 COPING OVERSAILING COURSE

MUD PHUSKA TILES SLAB CORNICE CORBLES

STRING COURSE

A.

WINDOW SILL

PIER (1)

B.

PIER (2)

FLOORING DPC

C. PILLARS

D.

TYPICAL SECTION OF BRICK WALL

THE BREADTH SHALL NOT EXCEED THREE TIMES THE THICKNESS AND THICKNESS ITSELF SHALL NOT EXCEED MORE THAN THREE BRICKS Drawing not to scale

Fig. 6.1 : Brick Work

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BRICK PILLARS Sub Head : Brick Work Clause : 6.2.4.1 EVEN COURSES

ODD COURSES 100

1 X 1½ BRICK

50 100

200

100

150

1 X 2 BRICK

150

200

150

100

1 X 2 ½ BRICK

200

100

200

100

200

50 100

300

200

100

1 ½ X 2 BRICK

100 50

2 X 2 BRICK

150

100

300

100

150

1 ½ X 1 ½ BRICK

400

100 50

200

Drawing not to scale All dimensions are in mm

Fig. 6.2 : English Bond

231

SUB HEAD 6.0 : BRICK WORK

BRICK BONDS Sub Head : Brick Work Clause : 6.2.4.1 EVEN COURSES

100

200

50

ODD COURSES

1 BRICK WALL 100

100

200

200

Q UEEN CLOSER

1½ BRICK WALL 100

100

200

200

200

200

200

2 BRICK WALL Drawing not to scale All dimensions are in mm

Fig. 6.3 : English Bond

CPWD SPECIFICATIONS 2009

232

BRICK BONDS (Contd.) Sub Head : Brick Work Clause : 6.2.4.1 EVEN COURSES

ODD COURSES

200

100

200

Q UEEN CLOSER

1 BRICK WALL

100

200

300

100

200

200

100

1½ BRICK WALL

200

400

100

100

2 BRICK WALL

200

70 70 60

300

300

200

50 80

20

70 60 70

40

150 200

60 70 70

70 60 70

CUT BRICK CORNER (MARUCONA) Drawing not to scale All dimensions are in mm

Fig. 6.4 : English Bond

233

SUB HEAD 6.0 : BRICK WORK

BRICK WORK IN ARCHES Sub Head : Brick Work Clause : 6.3 KEY

SPANDREL

EXTRADOS OR BACK T ES S W SOI R O S L OU V

FACE JOINTS NOT MORE THAN 5 MM THICK

SPRINGING POINT

SOFFIT OR INTRADOS

JOINTS VARYING FROM 5 TO 15 MM THICK

ABUTMENT. SPAN

PIER

PLAIN OR ROUGH

GAUGED CIRCULAR ARCH

SPAN

SPAN

ONE BRICK THICK

1½ BRICK THICK FLAT GAUGED ARCH

Drawing not to scale

Fig. 6.5 : Brick Work in Arches

CPWD SPECIFICATIONS 2009

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BRICK WORK IN CAVITY WALLS Sub Head : Brick Work Clause : 6.11.0 Coping roof level

M

M

Metal Tie or bonding unit Cavity to start from 75 mm above g.l.

Cavity < 50 > 115 G

L

(a) SECTION OF CAVITY WALL

230 mm wall

Normally 115 but not less than 75 mm in any case

Metal tie of bonding unit (b) SECTIONAL PLAN - MM Cavity 115 or less

115 or less

(c)

PLAN AT MM 75 mm or less

115 mm outside face

(d)

PLAN AT MM

75 mm

75 mm

(e) PLAN AT MM

Note : (1) Only one of the alternative a, b, c, d or e shall be applicable in each case. (2) Ties shall be placed sloping towards exterior side. Drawing not to Scale All dimensions are in mm

Fig. 6.6 : Brick Work in Cavity Walls (Fig. 6.6 Contd.)

235

SUB HEAD 6.0 : BRICK WORK

BRICK WORK IN CAVITY WALLS (Contd.) Sub Head : Brick Work Clause : 6.11.0 Wall Tie Position Unbonded Jamb

450

450

450

450

300 300 300 300 300 300

Cavity Wall

900 mm

900 mm

As Near to Opening as is Practicable (f) ELEVATION Metal Tie as per Detail

Metal Tie as per Detail (g) ISOMETRIC VIEW

20 x 5 mm

3 mm M.S. Hard Drawn Wire

20 cm

Course Height W id th

6 mm M.S. Bar

L

L = Thickness of Walls + Cavity > 2 x 115 + Cavity (for walls 115 mm or more)

L = Sum of Two Leaves + Cavity > 2 x 115 + Cavity (for walls 115 mm or more)

(h) BONDING UNIT (Preferably Precast R.C.C.)

(i) METAL TIE

2-6 mm M.S. Bars

2-3 mm M.S. Wire/Hard Drawn Wire (j) DETAILS OF REINFORCEMENT IN BONDING UNIT

Drawing not to Scale All dimensions are in mm

Fig. 6.6 (Contd.) : Brick Work in Cavity Walls

CPWD SPECIFICATIONS 2009

236

SUB HEAD : 7.0

STONE WORK

CONTENTS Clause No.

Brief Description

Page No.

List of Mandatory Tests

241

List of Bureau of Indian Standard Codes

242

7.0

Terminology

243

7.1

Random Rubble Stone Masonry

245

7.2

Coursed Rubble Masonry - First Sort

249

7.3

Coursed Rubble Masonry – Second Sort

251

7.4

Plain Ashlar Masonry

251

7.5

Punched Ashlar (Ordinary) Masonry

254

7.6

Moulded, Sunk, Carved Ashlar Masonry

254

7.7

Stone Veneering Work

255

7.8

Stone Chajja

257

7.9

Shelves, Coping, Plain, Cornices, String Courses etc.

258

7.10

Stone Jali

258

7.11

Dry Stone Cladding

259

7.12

Structural Steel Frame Work for Dry Stone Cladding

260

7.13

Adjustable Stainless Steel Cramps

261

Fig. 7.1

Stone Work

262

Fig. 7.2 to 7.7

Terminology

263

Fig. 7.8

Random Rubble Masonry

264

Fig. 7.9

Rubble Stone Masonry – Coursed

265

239

SUB HEAD 7 : STONE WORK

Fig. 7.10

Ashlar Stone Masonry

266

Fig. 7.11

Ashlar Stone Masonry (with Brick Backing)

267

Fig. 7.12

Moulded, Sunk, Carved - Stone Work

268

Fig. 7.13

Stone Work in Arches & Chajjas

269

Fig. 7.14, 7.15

Stone Veneering

270

Fig. 7.16

General Arrangement of Cramps

272

CPWD SPECIFICATIONS 2009

240

LIST OF MANDATORY TESTS Clause Test

Requirement

Field/ laboratory Test

Test Procedure

Stone

7.1.1 7.4 7.8 7.9

Not more than 2.5% by mass for sand stone and as specified in IS 1123 for other stones.

Laboratory

IS 1124

(ii) Transverse Not less than strength 7 N/mm2 (70 Kgf/cm2) for sand stone and as specified in IS 1123 for other stones. (iii) Resistance Not greater to wear than 2 mm on the average and 2.5 mm for any individual specimen for sand stone and as specified in IS 1123 for other stones. (iv) Durability Shall not develop signs of spalling, disintegration or cracks for sand stone and as specified in IS 1123 for other stones.

Laboratory

IS 1121 Part II

-do-

100 sqm/20 cum or part thereof or change of source as per direction of Engineerin- Charge -do-

Laboratory

IS 1706

-do-

-do-

Laboratory

IS 1126

-do-

-do-

(i) Water absorption

241

Minimum Qty. of material for carrying out test 50 sqm. for slabs and 10 cum in stone masonry

Frequency of Testing

Material

SUB HEAD 7 : STONE WORK

LIST OF BUREAU OF INDIAN STANDARD CODES S. No.

IS Code No.

Subject

1.

IS 737

Specifications for wrought aluminium and aluminium alloy, steel and strip for general engineering purpose.

2.

IS 1121 - (Pt. I)

Methods of determination of properties and strengths of natural building stones (Part-I compressive strength).

3.

IS 1122

Methods for determination of specific gravity of natural building stone

4.

IS 1123

Methods of identification of natural building stones.

5.

IS 1124

Methods of test of determination of water absorption, apparent, specific gravity and porposity of natural building stones.

6.

IS 1125

Methods of test of determination of weathering of natural building stone

7.

IS 1126

Methods of test for determination of durability of natural building stone

8.

IS 1128

Specification for Lime stone (Slab & Tiles).

9.

IS 1129

Recommendations for dressing of natural building stones.

10.

IS 1200 (Pt. IV)

Methods of measurements of building and Civil engineering works stone Masonry.

11.

IS 1197 (Pt. I)

Code of practice for construction of rubble stone masonry

12.

IS 1597 (Pt. II)

Code of practice for construction of ashlar stone masonry

13.

IS 1805

Glossary of terms relating to stones, quarrying and dressing

14.

IS 3620

Specification for latrite stone block for masonry

15.

IS 3622

Sand stone (Slab & Tiles)

16.

IS 4104 (Pt. I)

Code of practice for external facings and veneers (Part I-Stone facing).

17.

IS 4101 (Part II)

Code of practice for external facing and veneers: (Part II-Cement Concrete facing).

CPWD SPECIFICATIONS 2009

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7.0 STONE WORK 7.0 TERMINOLOGY Ashlar Stone masonry using dressed square stone blocks of given dimensions having faces perpendicular to each other and laid in courses. Bed Joint The joint where one stone presses on another for example, a horizontal joint in a wall or radiating joint between the voussoirs or arch (See Fig. 7.1 and 7.13) Block (a) Hollow (Open and Closed Cavity) Block: A concrete masonry unit with any one of the external dimension greater than the corresponding dimension of a brick and having one or more large holes or cavities which either pass through the block (open cavity) or do effectively pass through the block (closed cavity) and having the solid material between 50% and 75% of the total volume of the block calculated from the overall dimensions. (b) Solid Block: A concrete masonry unit with external dimensions greater than corresponding dimension of a brick and having solid material not less than 75% of the total volume of the block calculated from over all dimension. Bond An interlocking arrangement of structural units in a wall to ensure stability. Bond Stone (through Stone) Selected long stone used to hold a wall together transversely (See Fig. 7.8). Corbel Stone bonded well into the wall with part of it projecting out of the face of wall to form a bearing surfaces. Cornice A horizontal moulded projection which crowns or finishes either a wall, any horizontal division of wall, or any architectural feature (See Fig. 7.1C). Cramp A small piece of metal or the hardest or toughtest stone procurable, sunk in mortices and fixed across joints as additional ties. The ends of metal cramps are bent at right angles and stone cramps are dovetailed (See Fig. 7.1B). Course A layer of stones in wall including the bed mortar. Dowels Dowels are small sections of metal, stone or pebbles bedded with mortar in corresponding mortice in bed or side joint or adjacent stones (See Fig. 7.1A). Jamb The part of the wall at the side of an opening.

243

SUB HEAD 7 : STONE WORK

Joggle A key between the stones by providing a groove in one stone to take a corresponding concealed projection in the edges on the other stone (See Fig. 7.1B). Natural Bed The planes of stratification that occurs in a sedimentary rocks. Parapet A solid or pierced guard wall for flat stone terrace or balcony (or a bridge) or a curb wall at the lower part of a pitched roof which is exposed to atmosphere on face back and top (See Fig. 7.1C). Quoin A quoin is the external angle of wall or building. The term is also applied to stone specially selected and neatly dressed for forming such angle. Random Random or irregular size and shapes. Reveal The part of the jamb between the frame and the arris. Rubble Masonry Masonry built of stones either irregular in shapes as quarried or squared and only hammer dressed and having comparatively thick joints. As far as possible, stones for rubble masonry shall be angular. Skewback Sloping surface against which the springing of an arch rests. Spandrel Space between the haunches below the decking level. String Course A horizontal band, plain or moulded, usually projecting slightly from the face of wall (See Fig. 7.1C). Surfacing or Dressing of Stones The stones are dressed to have different surfaces as indicated below. Template or Bed Block A block of stone or concrete bedded on a wall to distribute the pressure from a concentrated load. Self Faced Surfaces Surfaces of stone slabs used for roofing, flooring, lintels etc. as obtained from quarry. Squared Back Surface Means the surface shall be dressed back at right angles to the face of the stone. Chisel Drafted Margin The dressing done with a drafting chisel in narrow strips of width generally 2 to 5 cm. Chisel drafted margin shall be punch dressed. Hammer Dressed Surface A hammer dressed stone shall have no sharp and irregular corners and shall have a comparatively even surface so as to fit well in masonry. Hammer dressed stone is also known as hammer faced, quarry faced and rustic faced. The bushing from the general wall face shall not be more than 40 mm on exposed face and 10 mm on faces to be plastered (Fig. 7.2). CPWD SPECIFICATIONS 2009

244

Rock Faced Surface A rock faced stone shall have a minimum of 25 mm wide chisel drafted margin at the four edges, all the edges being in the same plane (Fig. 7.3). Rough Tooled Surface A rough tooled surface shall have a series of bands, made by means of a plane chisel 4 to 5 cm wide, more or less parallel to tool marks all over the surface. These marks may be either horizontal, vertical or at an angle of 45° as directed (Fig. 7.4). The edges and corners shall be square and true. The depth or gap between the surface and straight edge, held against the surface shall not be more than 3 mm (Rough tooled stones are used where fairly regular plane faces are required for masonry work). Punched Dressed Surface A rough surface is further dressed by means of punch chisel to show series of parallel ridges. The depth of gap between the surface and a straight edge held against the surface shall not exceed 3 mm (Fig. 7.5). Punched dressed stones are used where even surfaces are required. Close Picked Surface A punched stone is further dressed by means of point chisel so as to obtain a finer surface, ridges or chisel marks left over being very tiny. The depth of gap between the surface and a straight edge kept over the surface shall not exceed 1.5 mm (Fig. 7.6). Fine Tooled Surface Close picked surface is further dressed so that all the projections are removed and fairly smooth surface is obtained. The surfaces shall have 3 to 4 lines per centimetre width depending on the degree of hardness of stone and degree of fineness required (Fig. 7.7). This type of dressing is commonly adopted for ashlar work. Polished Surface Surfaces having a high gloss finish. Polishing of stones shall be done by rubbing them with suitable abrasive, wetting the surface where necessary with water. Alternatively polishing of stones shall be done by holding them firmly on the top of revolving table to which some abrasive material like sand or carborundum is fed. The final polishing shall be performed by rubber or felt, using oxide of lime (called by trade name as putty powder) as a polishing medium. Moulded Cut to profile of a moulding with punched dressed surfaces, unless otherwise specified. 7.1 RANDOM RUBBLE STONE MASONRY 7.1.0 Material 7.1.1 Stone The stone shall be of the type specified such as granite, trap, limestone, sand stone, quartzite, etc. and shall be obtained from the quarries, approved by the Engineer-in-Charge. Stone shall be hard, sound, durable and free from weathering decay and defects like cavities, cracks, flaws, sand holes, injurious veins, patches of loose or soft materials and other similar defects that may adversely affect its strength and appearance. As far as possible stones shall be of uniform colour, quality or texture. Generally stone shall not contain crypst crystalline silica or chart, mica and other deleterious materials like iron-oxide organic impurities etc. Stones with round surface shall not be used. The compressive strength of common types of stones shall be as per Table 7.1 and the percentage of water absorption shall generally not exceed 5% for stones other than specified in Table 7.1. For laterite this percentage is 12%. 245

SUB HEAD 7 : STONE WORK

TABLE 7.1 Type of stone Granite Basalt Lime stone (Slab & Tiles) Sand stone (Slab & Tiles) Marble Quartzite Laterite (Block)

Maximum Water Absorption Percentage by weight 0.5 0.5 0.15 2.5 0.40 0.40 12

Minimum Compressive Strength kg./sq.cm. 1000 400 200 300 500 800 35

Note 1: Test for compressive strength shall be carried out as laid down in IS 1121 (Part I). Note 2: Test for water absorption shall be carried out as laid down in IS 1124. 7.1.2 Size of Stones Normally stones used should be small enough to be lifted and placed by hand. Unless otherwise indicated, the length of stones for stone masonry shall not exceed three times the height and the breadth on base shall not be greater than three-fourth of the thickness of wall, or not less than 150 mm. The height of stone for rubble masonry may be upto 300 mm. The selection and grading of stones for rubble masonry is largely done at site and the smaller stones are used in the hearting of wall. 7.1.3 Random Rubble Masonry shall be uncoursed or brought to courses as specified (Fig. 7.8 and 7.9). Uncoursed random rubble masonry shall be constructed with stones of sizes as referred to in para 7.0 and shapes picked up random from the stones brought from the approved quarry. Stones having sharp corners or round surfaces shall, however, not be used. 7.1.4 Random rubble masonry brought to the course is similar to uncoursed random rubble masonry except that the courses are roughly levelled at intervals varying from 300 mm to 900 mm in height according to the size of stones used. 7.1.5 Dressing Each stone shall be hammer dressed on the face, the sides and the beds. Hammer dressing shall enable the stones to be laid close to neighbouring stones such that the bushing in the face shall not project more than 40 mm on the exposed face. (i) Face stone: At least 25% stones shall be headers tailing into the work at least 2/3rd the thickness of wall in super structure masonry. Such stones shall not be less than 200 sq. cm in cross sections. (ii) Hearting Stones: The hearting or interior filling of a wall face shall consist of rubble stones not less than 150 mm in any direction, carefully laid, hammered down with a wooden mallet into position and solidly bedded in mortar. The hearting should be laid nearly level with facing and backing. (iii) Quoin Stone: Quoin stone shall be less than 0.03 cum in volume. (iv) Jamb stones: The jambs shall not be made with stones specified for quoins except that the stones which were required to be provided at 1 metre centre to centre on both the exposed faces shall here be provided only on the jamb and the length shall be equal to the thickness of the wall CPWD SPECIFICATIONS 2009

246

for wall upto 60 cm and a line of headers shall be provided for walls thicker than 60 cm as specified for bond. 7.1.5 (A) Courses The masonry shall be carried out in regular courses of height not exceeding 50 cm and masonry on any day will not be raised more than 60 cm in height when using mortars having compressive strength less than 20 kg./sq. cm at 28 days and 100 cm when using mortars exceeding this strength. 7.1.5 (B) Thickness of Joints The joint thickness shall not exceed 30 mm at any point on the face. Chips of the stone and spalls shall be wedged into seating bed of face stones to avoid excessive bed thickness. No pinning shall be allowed to avoid excessive joint thickness. 7.1.6 Mortar The mortar used for joining shall be as specified. 7.1.7 Laying Stone shall be laid on their natural bed and shall be solidly bedded full in mortar with close joints, chips of stone spalls be wedged into the work wherever necessary. No dry work or hollow spaces shall be allowed and every stone whether large or small shall be carefully selected to fit snugly the interstices between the large stones. Masonry shall be built breaking joints in all the three directions. Bond stone and headers shall be properly laid into the work and shall be marked by the contractor with white lead paint. The bond stones shall be provided as specified in para 7.1.8. The masonry work in wall shall be carried up true to plumb or to specified batter. Random rubble masonry shall be brought to the level courses at plinth, window sills, lintel and roof levels. Levelling shall be done with concrete comprising of one part of the mortar as used for masonry and two parts of graded stone aggregate of 20 mm nominal size. The masonry in structure shall be carried uniformly. Where the masonry of one part is to be delayed, the work shall be raked back at an angle not steeper than 45°. 7.1.7 (A) Raking out joints All the joints on the faces to be pointed or plastered shall be racked out with racking tool to a depth of 20mm while the mortar is still green. 7.1.8 Bond Stones Though bond stones shall be provided in walls upto 600 mm thickness, a set of two or more bond stones overlapping each other by at least 150 mm shall be provided in a line from face to back. In case of highly absorbent types of stones (porous lime stone and sand stone etc.) the bond stone shall extend about two-third into the wall, as through stones in such walls a set of two or more bond stones overlapping each other by at least 150 mm shall be provided. Each bond stone or a set of bond stones shall be provided for every 0.5 m2 of the wall surface and shall be provided at 1.5 m to 1.8 m apart clear in every course. In case of highly absorbent types of stones (porous lime stone and sand stone etc.) single piece bond stones may give rise to dampness. For all thicknesses of such walls a set of two or more bond stones overlapping each other by at least 15 cm shall be provided. Length of each such bond stone shall not be less than two-third of the thickness of the wall.

247

SUB HEAD 7 : STONE WORK

Where bond stones of suitable lengths are not available pre-cast cement concrete block of 1:3:6 mix (1 cement : 3 coarse sand: 6 graded stone aggregate 20 mm nominal size) of cross section not less than 225 square centimeters and length equal to the thickness. At least one bond stone or a set of bond stones shall be provided at 1.5 m to 1.8 m apart clear in every course. (Bond stones shall be marked suitably with paint as directed by the Engineer-in-Charge). 7.1.9 Quoin and Jamb Stones The quoin and jamb stones shall be of selected stones neatly dressed with hammer or chisel to form the required angle. Quoin stones shall not be less than 0.01 cum in volume. Height of quoins and jamb stones shall not be less than 15 cm. Quoins shall be laid header and stretcher alternatively. 7.1.10 Joints Stones shall be so laid that all joints are fully packed with mortar and chips. Face joints shall not be more than 20 mm thick. The joints shall be struck flush and finished at the time of laying when plastering or pointing is not to be done. For the surfaces to be plastered or pointed, the joints shall be raked to a minimum depth of 20 mm when the mortar is still green. 7.1.11 Scaffolding Single scaffolding having one set of vertical support shall be allowed. The supports shall be sound and strong, tied together by horizontal pieces, over which the scaffolding planks shall be fixed. The inner end of the horizontal scaffolding member may rest in a hole provided in the masonry. Such holes, however, shall not be allowed in pillars under one metre in width or near the skew back of arches. The holes left in masonry work for supporting scaffolding shall be filled and made good with cement concrete 1 : 3 : 6 (1 cement : 3 coarse sand : 6 stone aggregate 20 mm nominal size). 7.1.12 Curing Masonry work in cement or composite mortar shall be kept constantly moist on all faces for a minimum period of seven days. In case of masonry with fat lime mortar curing shall commence two days after laying of masonry and shall continue for at least seven days thereafter. 7.1.13 Protection Green work shall be protected from rain by suitable covering. The work shall also be suitably protected from damage, mortar dropping and rain during construction. 7.1.14 Measurements 7.1.14.1 The length, height and thickness shall be measured correct to a cm. The thickness of wall shall be measured at joints excluding the bushing. Only specified dimensions shall be allowed; anything extra shall be ignored. The quantity shall be calculated in cubic metre nearest to two places of decimal. 7.1.14.2 The work under the following categories shall be measured separately. (i) From foundation to plinth level (level one) : (a) work in or under water and or liquid mud, (b) work in or under foul positions. (i) Above plinth level and upto floor five level. (ii) Above floor five level to every floor/floors or part thereof. (iv) Stone masonry in parapet shall be measured together with the corresponding item in the wall of the storey next below. 7.1.14.3 No deduction shall be made nor extra payment made for the following : (i) Ends of dissimilar materials (that is joists, beams, lintels, posts, girders, rafters purlins, trusses, corbels, steps etc.) upto 0.1 sqm in section.

CPWD SPECIFICATIONS 2009

248

(ii) Openings each upto 0.1 sqm in area. In calculating the area of openings, any separate lintels or sills shall be included alongwith the size of opening but the end portions of the lintels shall be excluded and the extra width of rebated reveals, if any, shall also be excluded. (iii) Wall plates and bed plates, and bearing of chajjas and the like, where the thickness does not exceed 10 cm and the bearing does not extend over the full thickness of the wall. Note: The bearing of floor and roof shall be deducted from wall masonry. (iv) Drain holes and recesses for cement concrete blocks to embed hold fasts for doors, windows etc. (v) Building in masonry, iron fixture, pipes upto 300 mm dia, hold fasts of doors and windows etc. (vi) Forming chases in masonry each upto section of 350 sq cm. Masonry (excluding fixing brick work) in chimney breasts with smoke of air flues not exceeding 20 sq dm (0.20 sq m) in sectional area shall be measured as solid and no extra payment shall be made for pargetting and coring such flues. Where flues exceed 20 sq dm (0.20 sq m) sectional area, deduction shall be made for the same and pargetting and coring flues shall be measured in running metres stating size of flues and paid for separately. Aperture for fire place shall not be deducted and no extra payment made for splaying of jambs and throating. 7.1.14.5 Apertures for fire places shall not be deducted and extra labour shall not be measured for splaying of jambs, throating and making arch to support the opening. 7.1.14.6 Square or Rectangular Pillars: These shall be measured as walls, but extra payment shall be allowed for stone work in square or rectangular pillars over the rate for stone work in walls. Rectangular pillar shall mean a detached masonry support rectangular in section, such that its breadth does not exceed two and a half times the thickness. 7.1.14.7 Circular Pillars (Columns): These shall be measured as per actual dimensions, but extra payment shall be allowed for stone work in circular pillars over the rate for stone work in walls. The diameter as well as length shall be measured correct to a cm. 7.1.14.8 Tapered walls shall be measured net, as per actual dimensions and paid for as other walls. 7.1.14.9 Curved Masonry: Stone masonry curved on plan to a mean radius exceeding 6 metres shall be measured and included with general stone work. Stone work circular on plan to a mean radius not exceeding 6 metres shall be measured separately and shall include all cuttings and waste and templates. It shall be measured as the mean length of the wall. 7.1.15 Rate The rate shall include the cost of materials and labour required for all the operations described above and shall include the following : (a) Raking out joints for plastering or pointing done as a separate item, or finishing flush as the work proceeds. (b) Preparing tops and sides of existing walls for raising and extending. (c) Rough cutting and waste for forming gables cores, skew backs or spandrels of arches, splays at eaves and all rough cutting in the body of walling unless otherwise specified. (d) Bond stones or cement concrete bond blocks. (e) Leading and making holes for pipes etc. (f) Bedding and pointing wall plates, lintels, sills etc. in or on walls, bedding roof tiles and corrugated sheets in or on walls. (g) Building in ends of joists, beams, lintels etc. 7.2 COURSED RUBBLE MASONRY - FIRST SORT (FIG. 7.9) 7.2.1 Stone: Shall be as specified in 7.1.1. 249

SUB HEAD 7 : STONE WORK

7.2.2 Size of Stone: Shall be as specified in 7.1.2. 7.2.3 Dressing Face stones shall be hammer dressed on all beds, and joints so as to give them approximately rectangular block shape. These shall be squared on all joints and beds. The bed joint shall be rough chisel dressed for at least 80 mm back from the face, and side joints for at least 40 mm such that no portion of the dressed surface is more than 6 mm from a straight edge placed on it The remaining unexposed portion of the stone shall not project beyond the surface of bed and side joint. The bushing on the face shall not project more than 40 mm as an exposed face and 10 mm on a face to be plastered. The hammer dressed stone shall also have a rough tooling for minimum width of 25 mm along the four edges of the face of the stone, when stone work is exposed. 7.2.4 Mortar The mortar for jointing shall be as specified. 7.2.5 Laying All stones shall be wetted before use. The walls shall be carried up truly plumb or to specified batter. All courses shall be laid truly horizontal and all vertical joints shall be truly vertical. The height of each course shall not be less than 15 cm nor more than 30 cm. Face stones shall be laid alternate headers and stretchers. No pinning shall be allowed on the face. No face stone shall be less in breadth than its height and at least one third of the stones shall tail into the work for length not less than twice their height. The hearting or the interior filling of the wall shall consist of stones carefully laid on their proper beds in mortar; chips and spalls of stone being used where necessary to avoid thick beds of joints of mortar and at the same time ensuring that no hollow spaces are left anywhere in the masonry. The chips shall not be used below the hearting stone to bring these upto the level of face stones. The use of chips shall be restricted to the filling of interstices between the adjacent stones in hearting and these shall not exceed 10% of the quantity of stone masonry. The masonry in a structure shall be carried up uniformly but where breaks are unavoidable, the joints shall be raked back at angle not steeper than 45°. Toothing shall not be allowed. 7.2.6 Bond Stones Shall be as specified in 7.1.8 except that a bond stone or a set of bond stones shall be inserted 1.5 to 1.8 metres apart, in every course. 7.2.7 Quoins The quoins shall be of the same height as the course in which these occur. These shall be at least 450 mm long and shall be laid stretchers and headers alternatively. These shall be laid square on the beds, which shall be rough-chisel dressed to a depth of at least 100 mm. In case of exposed work, these stones shall have a minimum of 25 mm wide chisel drafts at four edges, all the edges being in the same plane. 7.2.8 Joints All bed joints shall be horizontal and all side joints vertical. All joints shall be fully packed with mortar, face joints shall not be more than one cm thick. When plastering or pointing is not required to be done, the joints shall be struck flush and finished at the time of laying. Otherwise, joints shall be raked to a minimum depth of 20 mm by raking tool during the progress of work, when the mortar is still green. CPWD SPECIFICATIONS 2009

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7.2.9 Curing, Scaffolding, Measurements and Rates. Shall be as specified under 7.1. 7.3 COURSED RUBBLE MASONRY - SECOND SORT (FIG. 7.9) 7.3.1 Stone : Shall be as specified in 7.1.1. 7.3.2 Size of Stone : Shall be as specified in 7.1.2. 7.3.3 Dressing: Shall be as specified in 7.2.3 except that no portion of dressed surface of joints shall show a depth of gap more than 10 mm from a straight edge placed on it and use of chips shall not exceed 15 per cent of the quantity of stone masonry. 7.3.4 Mortar The mortar for jointing shall be as specified. 7.3.5 Laying: Shall be as specified in 7.2.5 except that the use of chips shall not exceed 15% of the quantity of stone masonry and stone, in each course need not be of the same height but not more than two stones shall be used in the height of a course. 7.3.6 Bond Stone, Quoins: Shall be as specified in 7.2.6 and 7.2.7 respectively. 7.3.7 Joints All bed joints shall be horizontal and all side vertical. All joints shall be fully packed with mortar, face joints shall not be more than 20 mm thick. When plastering or pointing is not required to be done, the joints shall be struck flush and finished at the time of laying. Otherwise, the joints shall be raked to a minimum depth of 20 mm by raking tool during progress of work, where the mortar is still green. 7.3.8 Curing, Scaffolding, Measurement and Rates. Shall be as specified under 7.1. 7.4 PLAIN ASHLAR MASONRY (FIG. 7.10) 7.4.1(A) Stone shall be of the type specified. It shall be hard, sound, durable and tough, free from cracks, decay and weathering and defects like cavities, cracks, flaws, sand holes, veins, patches of soft or loose materials etc. before starting the work, the contractor shall get the stones approved by Engineer-in-Charge. 7.4.1(B) Kota Stone for Vineering Kota stone shall be of selected quality, hard, sound, dense & homogeneous in texture free from cracks, decay, weathering and flaws. They shall be machine cut to requisite size and thickness. They shall be of colour indicated in the drawings or as instructed by the Engineer-in-Charge. The stone shall have the top (exposed) face polished before being brought to site unless otherwise specified. Before starting the work, the contractor shall get the samples of kota stone approved from the Engineer-inCharge. Dressing : Every stone shall be cut to the required size and shape and fine machine dressed to the full depth so that a straight edge laid along the side of stone shall be in full contact with it. The thickness of the slab after it is dressed shall be 20, 25, 30 or 40 mm as specified in the item. Tolerance of ± 2 mm shall be allowed for the thickness. 7.4.1(C) Red Sand Stone & White Sand Stone Ashlar Masonry The stone shall be red or white as specified in the description of item. The stone shall be hard, sound, tough, free from cracks, decay & weathering. In case of red sand stone, white patches or streaks 251

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shall not be allowed. However scattered spots upto 10 mm diameter will be permitted. Before starting the work the contractor shall get samples of stone approved by the Engineer-in-Charge. 7.4.2 Size of Stone Normally stones used should be small enough to be lifted and placed by hand. The length of the stone shall not exceed three times the height and the breadth on base shall not be greater than threefourth of the thickness of wall nor less than 15 cm. The height of stone may be upto 30 cm. 7.4.3 Dressing Every stone shall be cut to the required size and shape chisel dressed on all beds and joints so as to be free from waviness and to give truly vertical and horizontal joints. In exposed masonry, the faces that are to remain exposed in the final position and the adjoining faces to a depth of 6 mm shall be the fine chisel dressed so that when checked with 60 cm straight edge, no point varies from it by more than 1 mm. The top and bottom faces that are to form the bed joints shall be chisel dressed so that variation from 60 cm straight edge at no point exceeds 3 mm. Faces which are to form the vertical joints should be chisel dressed so that variation at any point with 60 cm straight edge does not exceed 6 mm. Any vertical face that is to come against backing of masonry shall be dressed such that variation from straight edge does not exceed 10 mm. All angles and edges that are to remain exposed in the final position shall be true, square and free from chippings. A sample of dressed stone shall be prepared for approval of Engineer-in-Charge. It shall be kept at the worksite as a sample after being approved. 7.4.4 Mortar The mortar for jointing shall be as specified. 7.4.5 Laying All stones shall be wetted before placing in position. These shall be floated on mortar and bedded properly in position with wooden mallets without the use of chips or under pinning of any sort. The walls and pillars shall be carried up truly plumb or battered as shown in drawings. All courses shall be laid truly horizontal and all vertical joints shall be truly vertical. In case of ashlar work without backing of brick work or coursed rubble masonry, face stone shall be laid headers and stretchers alternately unless otherwise directed. The headers shall be arranged to come as nearly as possible in the middle of stretchers above and below. Stone shall be laid in regular courses of not less than 30 cm in height and all the courses shall be of same height, unless otherwise specified. For ashlar facing with backing of brick work or coursed rubble masonry (See Fig. 7.11) face stone shall be laid in alternate courses of headers and stretchers unless otherwise directed. Face stone and bond stone course shall be maintained throughout. All connected masonry in a structure shall be carried up nearly at one uniform level throughout, but where breaks are avoidable, the joint shall be made in good long steps so as to prevent cracks developing between new and old work. Bond stone provided in the masonry shall be payable in the item of Ashlar masonry. Neither any deduction will be made from the brick masonry for embedding the bond stone in the backing nor any extra payment shall be made for any extra labour involved in making holes in brick masonry backing. When necessary, jib crane or other mechanical appliances shall be used to hoist the heavy pieces of stones and place these into correct positions, care being taken that the corners of the stone are not damaged. Stone shall be covered with gunny bags, before tying chain or rope is passed over it, and it shall be handled carefully. No piece which has been damaged shall be used in work. CPWD SPECIFICATIONS 2009

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7.4.6 Bond Stones : Shall be as specified in 7.1.8. 7.4.7 Joints All joints shall be full of mortar. These shall be not more than 6 mm thick. Face joints shall be uniform throughout and a uniform recess of 20 mm depth from face shall be left with the help of the steel plate during the progress of work. 7.4.8 Pointing All exposed joints shall be pointed with mortar as specified. The pointing when finished shall be sunk from stone face by 5 mm or as specified. The depth of mortar in pointing work shall not be less than 15 mm. 7.4.9 Curing Masonry work in cement or composite mortar shall be kept constantly moist on all faces for a minimum period of seven days. In case of masonry with fat lime mortar, curing shall commence two days after laying of masonry and shall continue for at least seven days thereafter. 7.4.10 Protections Green work shall be protected from rain by suitable covering. The work shall also be suitably protected from damage, mortar dropping and rain during construction. 7.4.11 Scaffolding Double scaffolding having two sets of vertical supports shall be provided. The supports shall be sound and strong, tied together with horizontal pieces over which scaffolding planks shall be fixed. 7.4.12 Measurements The finished work shall be measured correct to a centimetre in respect of length, breadth and height. The cubical contents shall be calculated in cubic metre nearest to two places of decimal. 7.4.12.1 No deduction nor any extra payment shall be made for the following : (i) Ends of dissimilar materials (that is joists, beams, posts, girders, rafters, purlins, trusses, corbels, steps etc.) upto 0.1 sqm in section. (ii) Openings upto 0.1 sqm in area. In calculating the area of opening, any separate lintels or sills shall be included alongwith the size of the opening but the end portion of the lintels shall be excluded and extra width of rebated reveals, if any, shall also be excluded. (iii) Wall plates and bed plates and bearing of chajja and the like, where the thickness does not exceed 10 cm and the bearing does not extend over the full thickness of the wall. Note : The bearing of floor and roof slabs shall be deducted from wall masonry. (iv) Drainage holes and recesses left for cement concrete blocks to embed hold-fasts for doors and windows, building in the masonry iron fixture and pipes upto 300 mm diameter. (v) Stone walling in chimney breasts, chimney stacks, smoke or air flues not exceeding 0.20 sqm in sectional area shall be measured as solid and no extra measurement shall be made for pargetting and coring such flues. Where flues exceed 0.20 sqm in sectional area, deduction shall be made for the same and pargetting and coring flues paid for separately. 7.4.12.2 Square, Rectangular or Circular Pillars: Shall be measured and paid for as walls, but extra payment shall be allowed for such pillars and columns over the rate for stone work in walls. Rectangular pillars shall mean a detached masonry support, rectangular in section, such that its breadth shall not exceed two and half times the thickness. 7.4.12.3 Curved Stone Work: Stone work curved on a plan to a mean radius exceeding six metres shall be measured net and included with general stone work. Stone work circular on a plan to a mean radius 253

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not exceeding six metres shall be measured separately and extra payment shall be allowed and shall include all cutting and waste and templates. It shall be measured as the mean length of wall. 7.4.13 Rate The rate shall include the cost of materials and labour required for all the operations described above. Stone facing or wall lining upto and not exceeding 8 cm thickness shall be paid for under “Stone work for wall lining etc. (Veneer work)”. The stone work of thickness exceeding 8 cm shall be paid under relevant items of work. 7.5 PUNCHED ASHLAR (ORDINARY) MASONRY (FIG. 7.10) 7.5.1 Stone: Shall be as specified in 7.4.1. In case of red or white sand stone, stone shall be red or white as specified in the item. In red sand stone, white patches or streaks shall not be allowed. However, scattered spots upto 10 mm diameter will be permitted. 7.5.2 Size of Stone : Shall be as specified in 7.4.2. 7.5.3 Dressing: Shall be as specified in 7.4.3 except that the faces exposed in view shall have a fine dressed chisel draft 2.5 cm wide all round the edges and shall be rough tooled between the drafts, such that the dressed surface shall not be more than 3 mm from a straight edge placed over it. 7.5.4 Other Details The specifications for mortars, laying and fixing, bond stone, joints, pointing, curing, protections, scaffolding, measurements and rates shall be same as specified in 7.4. 7.6 MOULDED, SUNK, CARVED ASHLAR MASONRY (FIG. 7.12) 7.6.1 Stone : Shall be as specified in 7.4.1. 7.6.2 Dressing Every stone shall be cut to the required size and shape and chisel dressed on all beds and joints so as to be free from any waviness and to give perfectly vertical, horizontal, radial or circular joints with adjoining stones as the case may be. The dressed surface shall not be more than 3 mm from a straight edge placed on it. The face shall be gauged, cut, chamfered, grooved, rebated sunk or plain moulded and fine tooled as shown in the working drawings. The joints 6 mm from the face shall also be fine tooled so that straight edge laid along it is in contact with every point. It shall be finest surface which can be given to a stone with the chisel and without rubbing. In case of sunk or moulded masonry, the corner stone shall be dressed at true right angles or true to the shape as specified. The corners being straight and vertical. For arch (See Fig. 7.13), dome or circular work (See Fig. 7.12) the stone shall be dressed to require wedge shape so that joints shall be truly radial. 7.6.3 Sample The full size layout of the moulding etc. shall be prepared on platform from which sheet templates shall be cut and the stone dressed to templates to a uniform and fine finish. All visible angles and edge shall be true square and free from chippings. A sample of dressed stone shall be prepared for approval and it shall be kept as sample after being approved by Engineer-in-Charge. In case of ashlar moulded and carved columns a full size model of the required moulding, carving etc. shall be prepared in plaster of paris and kept at site of work as sample work after being approved by the Engineer-in-Charge. The stones shall be moulded and carved in accordance with the approved model to a uniform and fine finish.

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7.6.4 Other Details: Shall be as specified in 7.4.4., 7.4.5 and 7.4.7 to 7.4.11. 7.6.5 Centering and Shuttering Centering and shuttering required for arch dome or circular moulded work shall be constructed as directed by the Engineer-in-Charge. 7.6.6 Measurements The dimensions of the circumscribing rectangles of the dressed stone used in the work shall be measured correct to a cm and cubical contents shall be calculated in cubic metres, nearest to two places of decimal. 7.6.6.1 In case of sunk or moulded work the measurements for the work shall be taken course by course. The plain stone used in conjunction with sunk or moulded stone shall be measured and paid for under the relevant item of stone work. 7.6.6.2 Sunk or moulded work in rectangular, square and circular pillars, moulded cornices and string courses shall be measured under stone work sunk or moulded but extra payment shall be allowed over the general work in each case. No such extra payment shall be allowed for moulded string and plinth courses. 7.6.6.3 In case of arch dome or circular moulded work for arches exceeding six metres in clear span extra payment for additional cost of centering shall be made on the actual area of soffit including strutting, bolting, wedging, easing, striping and removal. 7.6.7 Rate The rate includes the cost of all materials and labour involved in all the operations described above, including centering and shuttering for arch, dome or circular moulded work. 7.7 STONE VENEERING WORK (FIG. 7.14, 7.15 & 7.16) Stone lining upto 8 cm shall be treated as veneering work and lining of greater thickness as plain Ashlar Masonry. 7.7.1 Stone : Shall be as specified in 7.4.1. The stone shall be gang saw cut into slabs of required thickness along the planes parallel to the natural bed of stone. 7.7.2 Dressing: Shall be as specified in 7.4.3 except that dressing at the back shall not be done, so as to ensure better grip with the hearting or backing. The dressed slabs shall be of the thickness as specified, with permissible tolerance of ± 2 mm. 7.7.3 Mortar Mortar for fixing shall be as specified. 7.7.4 Laying The stone shall be wetted before laying. They shall then be fixed with mortar in position without the use of chips or underpinning of any sort. 7.7.4.1 Where so desired, the adjoining stones shall be secured to each other by means of copper pins 75 mm long and 6 mm diameter or as specified. 7.7.4.2 Further the stones shall be secured to the backing by means of cramps. The material for cramps shall have high resistance to corrosion under conditions of dampness and against the chemical action of mortar or concrete in which cramps are usually embedded. 255

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Cramps shall be of 25 mm x 6 mm and 30 cm long in case of backing of stone masonry walls and brick masonry walls thicker than 230 mm. In case of backing with brick masonry walls 230 mm or less thick or RCC members, cramps shall be of 25 x 6 mm and length as per requirement made out of stainless steel or any other metal specified in para 7.7.4.6. Generally the outer length of cramp in half brick work backing shall be 115 mm and in one brick work backing it shall be 150 mm. Typical shape and details of cramps for such backing are indicated in Fig. 7.15 for general guidance. This can be modified as directed by the Engineer-in-Charge, if so required at site. Cramps shall be spaced not more than 60 cm apart horizontally. Alternatively the stone may be secured to the backing by means of stone dowels 10 x 5 x 2.5 cm as per shape indicated in Fig. 7.14 and the adjoining stone secured to each other by means of stainless steel cramps or copper pins of the specified size. Minimum one cramp/stone dowel shall be used to secure one slab to the backing. 7.7.4.3 Cramps may be attached to its sides (see Fig. 7.16A, 7.16B) or top and bottom (see Fig. 7.16C to F) or sides, top and bottom (see Fig. 7.16G & H). The minimum number of cramps required for fixing facing unit to the wall are illustrated in Fig. 7.16. The actual number of cramps and their sections, however, shall be as per requirements of design to carry the loads. 7.7.4.4 Where cramps are used to hold the unit in position only, the facings shall be provided with a continuous support on which the stones rest at the ground level and other storey levels, the support being in the form of projection from or recess into the concrete floor slab, or a beam between the columns or a metal angle attached to the floor slab or beams. These supports shall preferably be at vertical intervals not more than 3.5 m apart and also over the heads of all openings. Such supports shall also be provided where there is transition from thin facings below to thick facings above. 7.7.4.5 Alternatively cramps may be used to hold the units in position and in addition to support the units thus transferring the weight of the units to the backing. Such cramp should be properly designed as per IS 4101 (Part 1). 7.7.4.6 The cramps shall be of copper alloyed with zinc or nickel or of stainless steel of grade 304. 7.7.4.7 The pins, cramps and dowels shall be laid in cement mortar 1:2 (1 cement : 2 fine sand) and their samples got approved by the Engineer-in-Charge and kept at site. 7.7.4.8 The walls shall be carried up truly plumb. All courses shall be laid truly horizontal and all vertical joints truly vertical. The stone shall break joints on the face for at least half the height of the course, unless otherwise shown in the drawings. The stone shall be laid in regular courses not less than 20 cm height and all the stones shall be of the same height unless otherwise specified. No stone shall be less in length than one and a half times its height unless otherwise specified. 7.7.4.9 As far as possible the backing shall be carried up simultaneously with the face work. In case of reinforced cement concrete backing, the lining shall be secured to the backing after it has set and got cured. The cramps shall be fixed in concrete at the required positions, while laying. 7.7.5 Joints The joints shall be done with cement mortar 1: 3 (1 cement : 3 coarse sand). All joints shall be full of mortar. Special care shall be taken to see that the groundings for veneer work are full of mortar. If any hollow groundings are detected by taping the face stones, these shall be taken out and relaid. The thickness of joints shall be as small as possible, not exceeding 5 mm. For a close butt jointed facing the thickness shall not exceed 1.5 mm. The face joints shall be uniform throughout. Where joint filler or compound is to be used, the joints shall be raked out to a depth of at least 25 mm after the mortar in the joints has set sufficiently and the filler or compound applied. The joints may be CPWD SPECIFICATIONS 2009

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subsequently finished with a mortar suited to the appearance of the work. It is preferable to use joint sealing compounds where the facings are exposed to heavy rainfall and winds and their selections would depend upon local experience and availability of joint sealing compounds. In their absence only masonry mortars 1:3 (1 cement : 3 coarse sand) which are proved to be successful from local exposure conditions shall be used. 7.7.6 Other Details Specifications for pointing, curing, protections and scaffolding shall be specified under 7.4. 7.7.7 Measurements The length and breadth of the finished work shall be measured in metre correct to cm. The area should be calculated in sq. metre correct to two places of decimal. The veneering work curved on plan shall be measured as plain work, but extra payment shall be allowed for radii not exceeding six metres on external face. For radius beyond six metres the work shall be measured as plain work only, even the face may have to be dressed to curve. 7.7.8 Rate The rate includes the cost of materials and labour involved in all the operations described above, except for the cost of providing and fixing pins, dowels and metal cramps and ledges and supports, which shall be paid for separately unless otherwise stipulated in the item of work. 7.8 STONE CHAJJA (FIG. 7.13) 7.8.1 Stone slabs shall be hard, sound and durable. These shall be chisel dressed on all faces which are exposed to view and rough dressed at other surface. Angles shall be true and edge lines straight. The finished thickness shall be as stipulated with permissible tolerance of ± 2 mm. The length of stone slabs in chajja shall not be less than 60 cm unless otherwise specified. 7.8.2 In case of sloping chajja the stone shall be sloped as specified. It shall have minimum bearing of 20 cm measured horizontally on the wall and the bearing shall also be similarly sloped. Each slab shall have a hole in the centre of the bearing area through which the anchoring M.S. holding down bolt shall pass. The holding down bolts shall be 12 mm diameter and shall be bent at right angles at its lowest end and burried horizontally for at least 7 cm in a joint 30 cm below the bearing surface. Each holding down bolt shall be secured at top by suitable washer and nut. The chajjas shall be provided with cove supports, where cove is in brick masonry, it shall project out from the wall as under. 45 cm wide chajja, cove projection 15 cm, depth of cove 3 courses. 60 cm wide chajja, cove projection 20 cm, depth of cove 4 courses. 75 cm wide chajja, cove projection 25 cm, depth of cove 5 courses. 90 cm wide chajja, cove projection 30 cm, depth of cove 6 courses. 7.8.3 In case of horizontal chajja, the stone shall be fixed horizontally with a slight outer slope of about 1 cm. It shall have minimum bearing of 15 cm on the wall. Holding down bolts shall be provided, only where so specified. 7.8.4 Pointing The joints shall be pointed with 1:2 cement mortar (1 cement : 2 stone dust) with an admixture of pigment to match the stone shade, and properly cured. 7.8.5 Other Details Specifications for curing, protections and scaffolding shall be as specified under 7.4. 257

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7.8.6 Measurements The length and breadth of the finished work shall be measured correct to a cm. The area of chajja projecting beyond the wall shall be calculated in sq m correct to two places of decimal. In case of sloping chajja, the sloping breadth shall be measured correct to a cm and the area of chajja projecting beyond the wall shall be calculated in sq m correct to two places of decimal. 7.8.7 Rate The rate shall include the cost of all materials and labour involved in all the operations described above. Anchoring the coves shall be deemed to be included in the rate, only when it is so stipulated in the description of the item. 7.9 SHELVES, COPING, PLAIN, CORNICES, STRING COURSES ETC. 7.9.1 Stone Stone shall be of uniform colour and texture and of the kind as stipulated. 7.9.2 Dressing The exposed faces and sides of shelves shall be chisel dressed such that the dressed surface shall not be more than 3 mm from a straight edge placed on it. All visible angles and edges shall be free from chippings. The surfaces to be burried in the masonry shall be rough dressed. 7.9.3 Laying These shall be laid in mortar of specified mix and fixed as shown in drawing or as directed by the Engineer-in-Charge. 7.9.4 Other Details Specifications for pointing, curing, protections and scaffolding shall be as specified under 7.4. 7.9.5 Measurements 7.9.5.1 Shelves: The length and breadth shall be measured inclusive of bearings correct of a cm. The thickness shall be as specified with permissible tolerance of ± 2 mm. The area shall be calculated in sqm correct to two places of decimal. 7.9.5.2 Copings: The dimensions of the circumscribing rectangles of the dressed stones as used in work shall be measured correct to a cm. The cubical contents shall be calculated correct to two places of decimal in cum. 7.9.5.3 Plain Cornices, String Courses and Plinth Courses: The length, breadth and depth of the stone including bearing shall be measured correct to a cm. The cubical contents shall be calculated correct to two places of decimal in cu. m. 7.9.5.4 No deduction shall be made from the masonry of wall for the bearing of stone shelves, cornices, string courses. 7.9.6 Rate The rate shall include the cost of all materials and labour required in all the operations described above. 7.10 STONE JALI 7.10.1 Stone shall be as specified in 7.4.1. CPWD SPECIFICATIONS 2009

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7.10.2 Dressing and Fixing The stone shall be cut into slabs of required thickness so as to make jali of the specified thickness. The jali shall be cut as per pattern shown on the drawings. All exposed faces shall be fine tooled to a uniform and smooth finish. Fixing shall be done with the adjoining work in grooves, rebates etc., as shown in the drawing or as directed by the Engineer-in-Charge. A tolerance of + 2 mm shall be allowed in the specified thickness of the jali. 7.10.3 Stone jalis shall be fixed in grooves/rebates etc. to adjoining Stone work/Brick work/RCC as shown in the drawing or as directed by Engineer-in-Charge. Necessary sample for the same shall be got approved from the Engineer-in-charge before execution. The breakage of stone jail during fixing shall be the responsibilities of the contractor and replacement shall be provided at his risk and cost. 7.10.4 Measurements The length and breadth of the stone forming the jali including its borders shall be measured correct to a cm and the area shall be calculated in square metres nearest to two places of decimal. 7.10.5 Rate It includes the cost of labour and materials required for all the operations described above. It also includes the cost of making grooves or rebates in the adjoining work for fixing jali. 7.11 DRY STONE CLADDING 7.11.1 Material Stone shall be of the type as specified in the item. It shall be hard, sound durable and tough free from cracks, decay and weathering and defects like cavities cracks, flaws, holes, veins, patches of soft or loose materials etc. Thickness of stone shall be as specified Stone shall be cut with the gang saw to the required size and shape on all beds and joints so as to free from any waviness and to give truly vertical horizontal surface as required. The exposed face and sides of stones forming joints shall be such that the straight edge laid along the face of the stone is in contact with every point on it. All the visible angle and edges shall be square and free from chipping. The dressed stone shall be of the thickness specified with permissible tolerance of + 2 mm. Before starting the work, the contractor shall get the samples of stone approved by Engineer-Incharge. Approved sample shall be kept in custody of Engineer-in-Charge and stones supplied and used on the work shall conform to sample with regard to soundness, colour, veining and general texture. The stone shall be cut by gang saw into slabs of required thickness along the places parallel to the natural bed. When necessary double scaffolding for fixing the stone at greater heights, jib crane or other mechanical appliances shall be used to hoist the heavy pieces of stone and placed them into correct positions. Care shall have to be taken that corners of the stone are not damaged. Stone shall be covered with gunny bags before tying chain or rope is passed over and it shall be handled carefully. No pieces which has been damaged shall be used that work 7.11.2 Stacking and Storing Stone slabs are thin and brittle and should never be stacked flat across timber supports. They should therefore, be stacked on edge on timber or like runners. Packing pieces inserted between the slabs may be rope or timber. Slabs shall be well covered with plastic sheeting to protect them from any possible staining. 7.11.3 Scaffolding As specified in 7.4.11. 259

SUB HEAD 7 : STONE WORK

7.11.4 Fixing The size & shape of the cramps shall be as per drawing and as per directions of Engineer-in-charge. The samples of steel cramps should be approved in advance before starting the stone cladding work. The cramp shall be attached to top and bottom of the stone. The cramps shall have inbuilt adjustment for vertical and horizontal alignment. The cramps used to hold support and transfer the load of stone unit to the supporting structured steel shall be designed by the manufacturer and approval of the same shall be obtained from the Engineer-in-Charge. The minimum number of clamps required shall be as per requirement of design to carry the load of individual stone slabs. The cramps shall be spaced not more than 60 cm horizontally and vertically along the stone side for insertion of pins / bolt attached with the steel cramps. Adequate cutting in stone shall be made with precision instrument to hold the cramps pins at the joints. Stone shall be secured with clamps with high quality workmanship. The walls shall be carried up truly plumb. All the courses shall be laid truly horizontal and all the vertical joints truly vertical. The sequence of execution for cladding work shall be approved by the Engineer-in-Charge. Jointing: Joints horizontal and vertical shall be filled with weather sealant of make as approved by Engineer-in-charge with the help of pouring gun for filling the sealant. Before filling the joint with sealant, masking tape are required to be fixed on stones surface on both edges of joints of the stones, so that sealant may not spoil the surface of the stone. When all the joints are filled and sealant has dried, the masking tape may be removed. Protection: Work shall be protected from rain by suitable covering. The work shall also be suitably protected from damage and rain during construction. Measurement: The length and breadth shall be measured correct to a cm. The area shall be calculated in square metre correct to two places of decimal. Any opening of area 0.01 sqm. or less shall not be deducted. Rate: The rate includes the cost of materials and labour involved in all operations described above including cost of support scaffolding staging, sealant, pouring guns but excluding the cost of steel cramps drilling holes / making recesses in stones which shall be paid for separately. 7.12 STRUCTURAL STEEL FRAME WORK FOR DRY STONE CLADDING Specification for structural frame work for dry stone cladding are same specifications as for steel work in built up sections (welded or bolted). 7.12.1 Fixing of Frame The properly designed structural frame for withstanding the weight of stone slab are fixed/supported on wall surface with the help of M.S. brackets/lugs of angle iron/flat etc. which is welded at each junctions of member of frame and also embedded in cement concrete block 1:2:4 (1 cement: 2 coarse sand: 4 graded stone aggregate 20 mm nominal size) of size 300 x 230 x 300 mm. The concrete block can be made by cutting the hole of size as mentioned in brick wall and filling the hole with cement concrete including provision of necessary centring/shuttering for holding of concrete. The frame can also be supported on RCC surface with the help of approved expansion hold fastener by drilling the holes in RCC surface. Steel cramps are either welded or bolted to the frame (by making necessary holes in frame work) for holding of stone. 7.12.2 Measurement The mode of measurement shall be the same, as specified for steel work in built up section except that the weight of welding material shall not be added in weight of members for payment and nothing

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extra shall be paid for making holes for temporary fastening of members during erection before welding, which also includes cost of cement concrete block, centring and shuttering and making holes in walls, but excluding the cost of expansion fastener, steel clamps which shall be paid for separately. 7.12.3 Rate The rate shall include the cost of all labour and material involved in all the operation described above. 7.13 ADJUSTABLE STAINLESS STEEL CRAMPS The cramps shall be stainless steel of make approved by the Engineer-in-charge. 7.13.1 The weight of the stainless steel clamp (including weight of nut and washer) shall not be less than 260 gms. 7.13.2 Necessary holes at suitable locations are to be done on steel frame work for dry stone cladding to be fixed. 7.13.3 Necessary recessed are required to be done in stone slab which is required to be supported by clamps. 7.13.4 The one end of steel clamp is fixed on frame with nut and bolt and other end is inserted into recesses/hole for fixing the dry cladding stone on frame. 7.13.5 The rate includes cost of materials and other operations mentioned as above.

261

SUB HEAD 7 : STONE WORK

STONE WORK Sub Head : Stone Work Clause : 7.0

COPING PARAPET

CORNICE DOWEL

A

STRING COURSE

BED JOINT

DOWEL JOINT BED JOINT COPING METAL CRAMP PARAPET

JOGGLE JOINT WINDOW SILL

JOGGLE

C B

CORNICE

SECTION OF ASHLAR WITH BRICK BACKING JOGGLE JOINT

Drawing not to scale

Fig. 7.1 : Stone Work

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STONE WORK (Terminology) Sub Head : Stone Work Clause : 7.0

D

C

A

B

Fig. 7.3 : Rock Faced Stone Surface

Fig. 7.2 : Hammer Dressed Stone Surface

Fig. 7 .5 : Punched Stone Face Surface (Chisel drafted)

Fig. 7.6 : Closed Picked Stone Surface

Fig. 7.4 : Rough Tooled Stone Surface

Fig. 7.7 : Fine Tooled Stone Surface Drawing not to scale

263

SUB HEAD 7 : STONE WORK

RANDOM RUBBLE MASONRY Sub Head : Stone Work Clause : 7.1 Exposed face bushing not more than 40

Plastered face bushing not more than 10

Bond or through stone one per 0.5 sqm of wall surface

Chips not to exceed 20% of the quantity of stone masonry SECTION

ELEVATION

ELEVATION

Drawing not to scale All dimensions are in mm

Fig. 7.8 : Random Rubble Masonry

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Face Joints not more than 25

RUBBLE STONE MASONRY - COURSED Sub Head : Stone Work Clause : 7.2 & 7.3 FIRST SORT

SECOND SORT

Face Joints to be not more than 10

ELEVATION

ELEVATION

Plaster Surface Bushing not more than 10

Chips not to Exceed 15% of the Quantity of Stone Masonry Bond or Through Stone 1500 to 1800 Apart (Clear)

Quoin Stone 450 Long Min.

ODD COURSE

Face Joints to be not more than 20

Exposed face Bushing to be not more than 40

Quoin Stone 450 Long Min.

ODD COURSE

Bond or Through Stones 1500 to 1800 Apart (Clear)

Chips not to Exceed 10% of the Quantity of Stone Masonry

EVEN COURSE

EVEN COURSE

Drawing not to Scale All dimensions are in mm

Fig. 7.9 : Rubble Stone Masonry – Coursed

265

SUB HEAD 7 : STONE WORK

ASHLAR STONE MASONRY Sub Head : Stone Work Clause : 7.4 & 7.5

PUNCHED (ORDINARY)

PLAIN

Face Joints to be not more than 5 mm thick

ELEVATION

ELEVATION

Bond or Through Stone 1500 to 1800 Apart Clear

Bond or Through Stone 1500 to 1800 Apart Clear

ODD COURSE

ODD COURSE

EVEN COURSE

EVEN COURSE

Drawing not to scale All dimensions are in mm

Fig. 7.10 : Ashlar Stone Masonry

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ASHLAR STONE MASONRY (WITH BRICK BACKING) Sub Head : Stone Work Clause : 7.4.5

300

Brick Backing

200

Face Stone

ELEVATION

SECTION

100

Mortar

EVEN COURSE

200

200

ODD COURSE Drawing not to scale All dimensions are in mm

Fig. 7.11 : Ashlar Stone Masonry (with Brick Backing)

267

SUB HEAD 7 : STONE WORK

MOULDED, SUNK, CARVED – STONE WORK Sub Head : Stone Work Clause : 7.6

DOME

COLUMN Finial Stone Work in Ashlar Specially Moulded & Carved

Exposed Faces and Side Joints 6 mm from Face shall be Fine Tooled

Stone Work in Dome

Plain Ashlar Stone Work in Column

Stone Work in Ashlar Plain, Moulded & Carved Column

Sunk or Moulded Stone Work in Circular Pillars (Columns)

ELEVATION OF DOME WITH FINIAL

ELEVATION OF A COLUMN

Backing

Plain Ashlar B

Sunk L

SECTIONAL PLAN OF A WALL WITH A PROJECTION

Plain Ashlar Moulded Plinth Course Sunk Work Moulded

B

H

L

B

SECTION OF A WALL

SECTIONAL PLAN OF A PORCH PILLAR

Note : Sunk or Moulded Stone Work shown Shaded, to be measured as l x b x h

Drawing not to scale

Fig. 7.12 : Moulded, Sunk, Carved – Stone Work CPWD SPECIFICATIONS 2009

Sunk

268

STONE WORK IN ARCHES & CHAJJAS Sub Head : Stone Work Clause : 7.6 & 7.8

Spandrel

Extradose

Decking

Rise

Crown

Springing Skewback

Intradose Bed Joints Span

CIRCULAR ARCH

300

dt h Bre a

Anchoring bolt 12 mm φ 300

Triangular M.S. Washer Stone Chajja 70

Cove depth & Courses Bed Joints

200 600

Span

Brick Work Plaster

FLAT ARCH

CHAJJA

Drawing not to scale All dimensions are in mm

Fig. 7.13 : Stone Work in Arches & Chajjas

269

SUB HEAD 7 : STONE WORK

STONE VENEERING Sub Head : Stone Work Clause : 7.7 & 7.7.4.2 Gun Metal Cramp 300 mm Long Not more than 600 Apart

Brick Backing B

A

G

V Stone Veneer 50 mm Thick

C

R

Copper Pin

SECTIONAL PLAN

SECTIONAL PLAN

Gun Metal Cramp

Stone Dowel

Face Joints to be not more than 15 mm Thick

Gun Metal Cramp SECTIONAL ELEVATION AT 'P.Q.'

SECTIONAL ELEVATION AT 'R.S.' Stone Dowel

Brick Backing

Brick Backing

Gun Metal Cramp 200

Mortar 10 mm Thick

Stone Veneer 50 Thick

Stone Veneer 50 thick SECTIONAL AT 'X.Y'

ENLARGED DETAILS AT 'B'

6 mm - 75 Long Copper Pin 2 6 2

2 5 2 PART SECTIONAL PLAN AT 'A' 3 3 75

Stone Veneer

Stone Veneer

PART SECTIONAL PLAN AT 'C' 2 6

62

103

Gun Metal Cramp

6 1.5

PART SECTIONAL ELEVATION AT 'A'

PART SECTIONAL ELEVATION AT 'C'

25

25 0 25

10

15

6

25

25 25

50

25

5 11

25

0

6 50

300 LONG GUN METAL CRAMP

165 LONG GUN METAL CRAMP GENERAL FIXING ARRANGEMENT

Drawing not to scale All dimensions are in mm

Fig. 7.14 : Stone Veneering CPWD SPECIFICATIONS 2009

270

STONE DOWEL

25

STONE VENEERING (Typical Fixing Arrangement) Sub Head : Stone Work Clause : 7.7.4.2 & 7.7.4.6

50

30

25

25 L PLAN

PLAN

6 20

20 6 20

24

V = Variable as per Site Requirement Based on Thickness of Veneer Use

6 mm Square Gun Metal Pin

6

20

ELEVATION

70

Brick Wall

20

L = 115 MM for Half Brick Backing L = 150 MM for Full Brick Backing 25 V 6

FRONT ELEVATION

SIDE ELEVATION

Fig. 7.15A : Cramp for Brick Backing

Fig. 7.15B : Cramp for R.C.C. Work Backing

70

Non Corrosive Dash Fastener with Washer including Bolt of Min. Size 55 x 7 mm

R.C.C. Wall 8 98

Stone Veneering

Mortar as Specified Face Joints not to be more than 5 mm

Mortar 10 mm Thick 80 mm or as Specified FRONT ELEVATION SECTION

Fig. 7.15C :Typical Details of Cramps for R.C.C. Backing Drawing not to scale All dimensions are in mm

Fig. 7.15 : Stone Veneering (Typical Fixing Arrangement) 271

SUB HEAD 7 : STONE WORK

GENERAL ARRANGEMENT OF CRAMPS Sub Head : Stone Work Clause : 7.7.4.3

A

D

G

B

C

E

F

H

Note : Cramps arrangement is shown above for veneerings with longer sides vertical. For veneerings having the longer sides horizontal, cramps would be arranged to suit the altered positions.

Drawing not to scale

Fig. 7.16 : General Arrangement of Cramps

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SUB HEAD : 8.0

MARBLE WORK

CONTENTS Clause No.

Brief Description List of Mandatory Tests

Page 277

List of Bureau of Indian Standard Codes

278

8.0

General

279

8.1

Classification

279

8.2

Sizes and Tolerances

280

8.3

Physical Properties

280

8.4

Sampling

281

8.5

Marble Work - Table Rubbed and Polished (Plain Work)

281

8.6

Wall Lining / Veneer Work

284

8.7

Marble Stone Flooring and Marble Stone in Risers of Steps and Skirting

286

Fig. 8.1

Marble Stone Veneering (General Fixing Arrangement)

287

Fig. 8.2

Marble Stone Veneering (Typical Fixing Arrangement)

288

Fig. 8.3

General Arrangement of Cramps

289

Fig. 8.4

Marble Slab Urinal Partition

290

275

SUB HEAD 8.0 : MARBLE WORK

CPWD SPECIFICATIONS 2009

276

LIST OF MANDATORY TESTS Material Clause

Marble

Granite

Test

8.3 (i) Moisture (Table 8.2) Absorption (ii) Hardness Test (iii) Specific Gravity (i) Moisture (ii) Specific Gravity

Field/ Laboratory Test

Minimum Frequency quantity of material/ of testing work for carrying out the test Laboratory IS 1124 50 Sq.m. 100 sqm. or part thereof. -doMho’s Scale -do-do-doIS 1122 -do-do-doIS 1124 -do-do-doIS 1122 -do-do-

277

Test Procedure

SUB HEAD 8.0 : MARBLE WORK

LIST OF BUREAU OF INDIAN STANDARDS CODES S. No.

IS. No.

Subject

1.

IS 1122

2.

IS 1124

3. 4. 5. 6.

IS 1130 IS 4101 (Part 1) IS 3316 IS 14223 (Part 1)

Method of test for determination of true specific gravity of natural building stones. Method of test for determination of water absorption, apparent specific gravity and porosity of natural building stones. Marble (blocks, slabs and tiles). Code of practice for external facing and veneers: Stone facing. Specifications for structural granite Polished Building Stones (Part-1) Granite

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278

8.0 MARBLE WORK 8.0 GENERAL Marble shall be hard, sound, dense and homogeneous in texture with crystaline texture as far as possible. It shall generally be uniform in colour and free from stains, cracks, decay and weathering. 8.0.1 Marbles are metamorphic rocks capable of taking polish, formed from the re-crystalization of lime stones or dolomitic lime stones and are distinguished from lime stone by even visibly crystalined nature and nonflaggy stratification. Note : Marble is a product of nature hence it is difficult to guarantee uniformity of colour, veining or other characteristics that may be represented in any sample submitted. A sample will indicate only an average of colour, veining and other general texture and specified finish. 8.1 CLASSIFICATION The marble blocks, slabs and tiles shall be classified broadly in the following two categories: 8.1.1 White Marble Raj Nagar (plain white) Marble: It shall be plain white marble with coarse grains predominantly showing mica particles giving reflection in light. 8.1.2 Coloured Marble (i) Plain Black Marble Black marble sawn along veins locally known as ‘Peta Pasu sawing’ available at Bhainslana. (ii) Black Zebra Marble (a) Bhainslana Black Zebra Marble: Black marble having grey or white veins available at Bhainslana. (b) Kishangarh Black Zebra Marble: Black marble with grey and/or white veins available at Kishangarh. (c) Abu Black Zebra Marble: Black marble having white patches and streaks available at Abu. (d) Narnaul Black Zebra Marbles: Black marble with thin white veins available at Narnaul. (e) Makrana Dhobi Doongri Zebra Marble: Greyish black marble with white flowery pattern available at Dhobi Doongri. (iii) Green Marble (a) Baroda Green Marble: Dark green marble with flowery pattern available at Baroda. (b) Abu Green Marble: Light green marble with green and/or brown streaks on white ground available at Ambaji. (c) Falna Green Marble: Green marble with prominent yellowish pattern available at Falna. (d) Bundi Green Marble: Green marble with pinkish shades available at Umar, (Bundi). (iv) Grey Marble (a) Kumari Grey Marble: Grey marble having light blue shades available at Makrana. (b) Bundi Grey Marble: Grey Marble with pink or green or black streaks available at Umar (Bundi). (v) Brown Marble (a) Bar Brown Marble/Brown Marble with light and dark brown shades available at Bar. (b) Narnaul Brown Marble Brown marble having teak wood shades available at Narnaul. 8.1.3 Granite Stone It shall be of any colour and size as directed by Engineer-in-Charge. Granite shall be plain machine cut and mirror polished. The stone shall be smooth and of even surface without holes or pits.

279

SUB HEAD 8.0 : MARBLE WORK

8.2 SIZES AND TOLERANCES The size of marble blocks, slabs and tiles shall be as mentioned in Table 8.1. TABLE 8.1 Sizes of Marble Blocks, Slabs and Tiles 1. 2. 3.

Blocks Slabs Tiles

Length 30 to 250 70 to 250 10 to 60

Width 30 to 100 30 to 100 10 to 60

Thickness 30 to 90 2 to 15 0.8 to 2.4

Notes: (1) All dimensions are in centimetre. (2) The length and width, of the blocks shall be in multiple of 30 cm. (3) Length and width of slab shall be in multiple of 10 cm. and thickness in multiple of 1 cm. (4) Tiles shall be square cut and linear dimensions in multiple of 10 cm. (5) Only slabs and tiles shall be machine cut and factory made. (6) For 8 mm thick tiles, special precautions will be required for fixing them like using special adhesive as per manufacturer’s specifications. Such tiles are not suitable for outside veneering work exposed to rains/sun if used in large areas in continuous stretches. For tiles of thickness 20 mm and above cramps may be provided if approved by Engineer-in-Charge. Tolerance The following tolerances shall be allowed in the dimension of blocks, slabs and tiles: Tolerance Blocks (a) Length + 2 per cent (b) Width + 2 per cent (c) Thickness + 2 per cent Slabs (a) Length + 2 per cent (b) Width + 2 per cent (c) Thickness + 3 per cent Tiles (a) Linear dimension + 3 per cent (b) Thickness + 1 per cent The sizes other than those mentioned above may be provided as directed by the Engineer-in-Charge and nothing extra shall be payble on this account. 8.3 PHYSICAL PROPERTIES 8.3.1 The physical properties of marble for blocks, slabs and tiles and method of tests are mentioned in Table 8.2. TABLE 8.2 Physical Properties of Marble & Granite

Characteristic (1) Moisture absorption after 24 hrs immersion in cold water (2) Hardness (3) Specific Gravity

Marble Granite Marble Requirements Method of test Granite Requirement Method of test Max. 0.4% IS 1124 Max. 0.50% IS 1124 by weight Min. 3 Min. 2.5

CPWD SPECIFICATIONS 2009

Mhos scale IS 1122

280

__

Min. 2.6

__

IS 1122

8.3.2 Approval of Sample Before starting the work, the contractor shall get samples of marble approved by the Engineer-inCharge. Approved samples shall be kept in the custody of the Engineer-in-Charge and the marble supplied and used on the work shall conform to samples with regard to soundness, colour, veining and general texture. 8.4 SAMPLING In any consignment all the blocks/slabs/tiles of the same group, size and finish shall be grouped together to constitute a lot. Sample shall be selected and tested separately for each lot for determining its conformity or otherwise to the requirements of the specification. The number of blocks/slabs/tiles to be selected for the samples shall depend upon the size of the lot and shall be in accordance with the Table 8.3. TABLE 8.3 Sample Size and Criteria for Conformity Number of Blocks slabs/Tiles in the lot (1) Up to 25 26 to 100 101 to 200 201 to 500 501 to 1000

Number of blocks slabs/ Tiles to be selected in sample (2) 3 5 8 13 20

Permissible number of defectives (3) 0 0 0 0 1

Sub sample size in no. (4) 2 2 3 4 5

Note: The blocks/slabs/tiles in the sample shall be taken at random and in order to ensure to randomness of selection, random tables may be used. Explanation 1 : All the blocks/slabs/tiles, selected in the sample, shall be examined for dimensions workmanship and general requirements. Any block/slab/tile failing in any one or more of the above requirements shall be considered as defective. A lot shall be considered as conforming to these requirements if the number of defectives obtained is not more than permissible no. of defectives given in Col. 3 of table 8.3 Explanation 2 : The lot having been found satisfactory with respect to dimensions, workmanship and general requirement shall be tested for physical properties of the marble. For this purpose a sub sample of the size given in Col. 4 of Table 8.3 shall be selected at random. These blocks/slabs/tiles in the sub sample shall be tested for moisture absorption, hardness and specified gravity. The lot shall be considered having satisfied the requirements of the physical properties if none of the blocks/slabs/tiles tested for the requirements fails in any of these tests. 8.5 MARBLE WORK - TABLE RUBBED AND POLISHED (PLAIN WORK) Marble work in steps, jambs, columns and other plain work shall be as specified below: Joints in staircase treads, kitchen platforms shall be permitted only at curvature or when width/length is more than 0.6/2 mtrs. respectively. Number of joints in each direction shall not be more than one number for every 2 mtrs. length beyond the initial 2.00 m length. Additional joints due to curvature or for providing fixture shall be provide judiciously as given in sketch ‘A’ below.

281

SUB HEAD 8.0 : MARBLE WORK

1m

0.6 m

3.8 m

0.9 m 0.6 m (I) TREAD/STEPS IN STAIR CASE

(II) TYPICAL KITCHEN PLATFORM INDICATING LOCATION OF JOINT IN MARBLE TOP

SKETCH (A) 8.5.1 Dressing, Cutting and Rubbing Every marble stone shall be gang saw/machine cut to the required size and shape, chisel dressed machine finished on all beds and joints, so as to be free from any waviness and to give truly vertical, horizontal, radial or circular joints as required. The exposed faces and sides of stones forming joints upto 6mm. from the face shall be fine tooled machine cut such that a straight edge laid along the face of the stone is in contact with every point on it. All window sills, tread of steps, counters vanities moulding edges etc. shall be machine cut & polished to give high gloss mirror finish as per direction of Engineerin-Charge. These surfaces shall then be rubbed smooth. All visible angles and edges shall be true, square and free from chipping. Beyond the depth of 6 mm from face, the joints shall be dressed with a slight splay so that the thickness of joint increases, in an inverted V shape as shown in Fig. below. The surfaces of the stones coming in contact with backing need not be chisel dressed. EXTERNAL FACE 1.5 mm 6 mm

INVERTED V-SHAPE JOINT A sample of dressed and rubbed stone shall be prepared for approval and it shall be kept on worksite after being approved by the Engineer-in Charge. 8.5.2 Mortar The mortar used for jointing shall be as specified. 8.5.3 Laying All marble stones shall be wetted before placing in position. These shall then be floated on mortar and bedded properly in position with wooden mallets without the use of chips or under pinning of any sort. The walls and pillars shall be carried up truely in plumb or battered as shown in the drawings. All courses shall be laid truely horizontal and all vertical joints shall be truely vertical. In case of work without backing of brick work or coursed rubble masonry, face stone shall be laid in headers and stretchers alternatively unless otherwise directed. The headers shall be arranged to come

CPWD SPECIFICATIONS 2009

282

as nearly as possible in the middle of stretchers above and below. Stone shall be laid in regular courses of not less than 15 cm in height and all courses shall be of the same height unless otherwise specified. For work facing with backing of brick work or coursed rubble masonry, face stone shall be laid in alternate courses of header and stretchers unless otherwise directed. Face stone and bond stone courses shall have break joint on the face of atleast half the height of the standard course and the bond shall be carefully maintained through out. All the connected masonry in a structure shall be carried up nearly at one uniform level throughout but where breaks are unavoidable the joints shall be made in good long steps so as to prevent cracks developing between new and old work. When necessary jib crane or other mechanical appliances shall be used to hoist the heavy pieces of stones and place these in to correct positions, care being taken that the corners of the stone are not damaged. Stone shall be covered with gunny bags, before putting chain or rope is passed over it, and it shall be handled carefully. No piece which has been damaged shall be used in work. The matching of grains shall be carried out as directed by the Engineer-in-Charge. 8.5.4 Bond Stone Bond or through stones running right through the thickness of walls, shall be provided in walls upto 60 cm thick and in case of wall above 60 cm thickness a set of two or more bond stones overlapping each other by atleast 15 cm shall be provided in a line from face to back. At least one bond stone or a set of bond stones shall be provided for every 0.5 sqm of the wall surface. All bond stones shall be marked suitably as directed by the Engineer-in-Charge. 8.5.5 Joints The depth of joints 6 mm from the face shall be uniform and as fine as possible but shall be not more than 1.5 mm thick on the exposed face. Beyond the depth of 6 mm from face, the thickness of joints shall increase in an inverted V shape so as to give good mortar bond between two stones. The inverted portion of the joints shall be filled with bedding mortar and the face 6 mm portion with pointing mortar. 8.5.6 Curing The work shall be kept constantly moist on all faces for a period of atleast seven days. 8.5.7 Finishing After the marble work is cured, it shall be rubbed with carborandum stone of different grades no. 60, 120 and 320 in succession or with electrical rubbing machines rubbed with carborandum items 0 to 6 nos.in succession, so as to give a plane true and highly smooth surface. It shall then be cleaned with a solution of oxalic acid, washed and finished clean. 8.5.8 Protection Green work shall be protected from rain by suitable coverings. The work shall also be suitably protected from damage during construction. 8.5.9 Scaffolding Double scaffolding having two sets of vertical supports shall be provided where necessary. The supports shall be sound and strong, tied together by horizontal pieces over which the scaffolding plank shall be fixed. 8.5.10 Tolerances As per para 8.2 Note: The above Para 8.5. also applies to the Ashlar masonry referred in Chapter No. 7.0 - Stone Work. 283

SUB HEAD 8.0 : MARBLE WORK

8.5.11 Measurements For plain work: Measurements shall be taken correct to a cm in length and breadth and correct to 0.5 cm in thickness. 8.5.11.1 In the case of radially dressed or circular stone used in the work, the dimensions of the circumscribing rectangle of the dressed stone, shall be measured correct to a centimetre and thickness, correct to 0.5 cm. The cubical contents shall be calculated in cubic decimetre nearest to two places of decimal. 8.5.11.2 The marble work in arches and domes shall be measured as for plain work, but extra shall be allowed for such work over the rate for plain work. 8.5.11.3 Sunk or moulded work in marble shall be measured by volume as per plain marble work or work in arches or domes as the case may be on the basis of circumscribed rectangular block of the finished work but extra shall be paid for such work over the rate for plain work for work in arches and domes. For the purpose of extra payment, volume of every stone sunk or moulded shall be considered. 8.5.12 Rate The rate includes the cost of materials and labour required for all the operations i/c cutting of recesses in wall cutting moulding corners edge rounding finishing & polishing as specified. 8.5.13 Use of Finished Marble Slabs and Tiles In case such finished tiles are used, these shall be measured and paid for separately. 8.6 WALL LINING/VENEER WORK 8.6.1 Unless and otherwise specified in the nomenclature of the item, the marble slabs used for wall lining/veneer work shall be gang saw cut (polished & machine cut) and conform to dimensions given in Table 8.1 above. Back shall not be polished/ cut in order to ensure a good grip with the hearting of backing. The cut slabs shall be of the thickness as specified with a tolerance permissible under para 8.2 above. The tolerance in wall lining when straight edge of 3 m length is placed should not be more than 2 mm. 8.6.2 Laying The stone shall be wetted before laying. They shall then be fixed with mortar in position without the use of chips or under pinning of any sort. Care shall be taken to match the grains of veneer work as directed by the Engineer-in-Charge. For purpose of matching the grains, the marble slabs shall be selected judiciously having uniform pattern of veins/streaks. Preferably the slabs shall be those got out of the same block from the quarry. The area to be veneered shall be reproduced on the ground and the marble slabs laid in position and arranged in the manner to give the desired matching of grains. Any adjustment needed for achieving the best results shall be then carried out by replacing or interchanging the particular slabs. Special care shall be taken to achieve the continuity of grains between the two slabs one above the other along the horizontal joints. This shall then be got approved by the Engineer-inCharge and each marble slabs numbered properly and the same number shall be marked on a separate drawing as well as on the surface to be actually veneered, so as to ensure the fixing of the particular slabs in the correct location. For the facing of the columns also the same procedure as mentioned above shall be followed. 8.6.2.1 Where so desired, the adjoining stones shall be secured to each other by means of copper pins 75 mm long and 6 mm diameter or as specified. CPWD SPECIFICATIONS 2009

284

8.6.2.2 The stones shall be secured to the backing by means of cramps. The material for cramps shall have high resistance to corrosion under conditions of dampness and against the chemical action of mortar or concrete in which cramps are usually embedded. Cramps shall be of 25 × 6 mm and 30 cm long in case of backing of stone masonry walls and brick masonry walls thicker than 230 mm. In case of backing with brick masonry walls 230 mm or less thick or RCC members cramps shall be of 25 × 6 mm and length as per requirement made out of gun metal or any other metal specified in para 8.6.2.6. Generally the outer length of cramp in half brick work backing shall be 115 mm and in one brick work backing it shall be 150 mm. Typical shape & details of cramps for such backing are as indicated in Fig. 8.2 for general guidance. This can be modified as directed by the Engineer-in-Charge if so, required at site. Cramps shall be spaced not more 60 cm apart horizontally. Alternatively the stone may be secured to the backing by means of stone dowels 10 x 5 x 2.5 cm as per shape indicated in Fig. 8.1. 8.6.2.3 The adjoining stones shall be secured to each other by means of gun metal cramps or copper pins of the specified size. Cramps may be attached to its sides (see Fig. 8.3A, 8.3B) or top and bottom (See Fig. 8.3C, D, E, F) or sides, top and bottom (see Fig. 8.3G, 8.3H). The general arrangement of cramps required for fixing facing unit to the wall are illustrated in Fig 8.3. The actual number of cramps and their sections, however, shall be as per requirements of design to carry the loads. 8.6.2.4 Where cramps are used to hold the unit in position only, the facings shall be provided with a continuous support on which the stones rest at the ground level and other storey levels, the support being in the form of projection from or recess into the concrete floor slab, or a beam between the columns or a metal angle attached to the floor slab or beams. These supports shall preferably be at vertical intervals not more than 3.5 m apart and also over the heads of all openings. Such supports shall also be provided where there is transition from thin facing below to thick facings above. 8.6.2.5 Alternatively cramps may be used to hold the units in position and in addition to support the units thus transferring the weight of the units to the backing. Such cramps should be properly designed as per IS 4101 (Part 1). 8.6.2.6 The cramps may be of copper alloyed with zinc, tin, nickel, lead or stainless steel. 8.6.2.7 The pins, cramps and dowels shall be laid in cement mortar 1:2 (1 cement : 2 fine sand) and their samples got approved by the Engineer-in-Charge and kept at site. 8.6.3 Joints All joints shall be full of mortar. Special care shall be taken to see that groundings for veneer work are full of mortar. If any hollow groundings are detected by tapping the face stones, these shall be taken out and relaid. The thickness of the face joints shall be uniform, straight and as fine as possible, not more than 1.5 mm and in the face joint, the top 6 mm depth shall be filled with mortar specified for the pointing. 8.6.4 Mortar The mortar used for jointing slabs shall be as specified. 8.6.5 Curing, Finishing, Protection and Scaffolding It shall be as specified under 8.5.6, 8.5.7, 8.5.8 and 8.5.9. 8.6.6 Measurements The length and breadth shall be measured correct to a cm. In case of radially dressed or circular slabs used in the work, the dimensions of the circumscribing rectangles of the dressed stone used in the work, shall be measured & paid for. The area shall be calculated in sqm nearest to two places of decimal. 285

SUB HEAD 8.0 : MARBLE WORK

Marble work in lining upto 4 cm thickness shall be paid by area under veneer work and lining of greater thickness paid by volume under plain marble work. 8.6.7 Rate The rate includes the cost of materials and labour required for all the operations described above except for the cost of providing and fixing of dowel and cramps which shall be paid for separately, unless otherwise stipulated in the item of work. When factory made finished slabs and tiles are used, no further finishing as mentioned in para 8.5.7 shall be required nor anything extra shall be payable. 8.7 MARBLE STONE FLOORING AND MARBLE STONE IN RISERS OF STEPS AND SKIRTING Refer to relevant clause in subhead 11.0 of flooring of CPWD Specifications 2009. 8.7.0 Marble Slab Urinal Partitions The partitions shall be of marble slab embedded in the wall. The size and shape of the marbles slab shall be as per direction of Engineer-in-Charge. The finished thickness shall be 18 mm. The specifications for marble/granite stone work, in general, shall be as specified. The marble granite stone shall be cut into slabs of required thickness and shall be one piece. (Fig. 8.4). 8.7.1 Finishing The partition of the slab to be embedded in the masonry shall be rough dressed. Dressing and rubbing of the exposed portion of the slab shall be as described. The dressed slab shall be of the thickness as specified with a tolerance of + 1.5mm. The slab shall be got approved from the Engineer-inCharge before fixing. 8.7.2 Fixing shall be as specified except that the recess shall be 7.5 cm wide. Fixing shall be done by cutting chase with chase cutter/fine tools in a recess of 7.5 cm X 7.5 cm filled with cement concrete 1:2:4 (1 cement : 2 coarse sand : 4 graded stone aggregate 6mm nominal size). Fixing can also be done by epoxy grout in a chase of 2.0 X 7.5 cm as per direction of Engineer-in-Charge. 8.7.3 Measurement shall be as per para 8.6.6. 8.7.4 Rate shall include the cost of labour and materials involved in all the operations described above including the leaving/cutting of recess in the wall, moulding, curves, edge rounding, finishing and polishing as specified.

CPWD SPECIFICATIONS 2009

286

MARBLE STONE VENEERING Sub Head : Marble Work Clause : 8.6.2.2 Gun Metal Cramp 600 mm Long Not more than 600 Apart

Brick Backing B

A

G

V Stone Veneer 50 mm Thick

C

R

Copper Pin

SECTIONAL PLAN

SECTIONAL PLAN

Gun Metal Cramp

Stone Dowel

Face Joints to be not more than 15 mm Thick

Gun Metal Cramp SECTIONAL ELEVATION AT 'P.Q.'

ENLARGED DETAILS AT 'R.S.' Stone Dowel

Brick Backing

Brick Backing

Gun Metal Cramp

Mortar 10 mm Thick

200

Stone Veneer 50 Thick

Stone Veneer 50 thick SECTION AT 'X.Y'

ENLARGED DETAILS AT 'B'

6 mm - 75 Long Copper Pin 2 6 2

2 5 2 PART SECTIONAL PLAN AT 'A' 3 3 75

Stone Veneer

Stone Veneer

PART SECTIONAL PLAN AT 'C' 2 6

62

103

Gun Metal Cramp

5 1.5

PART SECTIONAL ELEVATION AT 'A'

PART SECTIONAL ELEVATION AT 'C'

25

25 0 25

10

15

6

50

0

25 5 11

25 25

25

25

25

6 50

300 LONG GUN METAL CRAMP

165 LONG GUN METAL CRAMP

STONE DOWEL

Drawing not to scale All dimensions are in mm

Fig. 8.1 : Marble Stone Veneering (General Fixing Arrangement) 287

SUB HEAD 8.0 : MARBLE WORK

MARBLE STONE VENEERING (Typical Fixing Arrangement) Sub Head : Marble Work Clause : 8.6.2.2

50

30

25

25 L PLAN

PLAN

6 20

20 6 20

24

V = Variable as per Site Requirement Based on Thickness of Veneer Use

6 mm Square Gun Metal Pin

6

20

ELEVATION

70

Brick Wall

20

L = 115 MM for Half Brick Backing L = 150 MM for Full Brick Backing 25 V 6

FRONT ELEVATION

SIDE ELEVATION

Fig. 8.2A : Cramp for Brick Backing

Fig. 8.2B : Cramp for R.C.C. Work Backing

70

Non Corrosive Dash Fastener with Washer including Bolt of Min. Size 55 x 7 mm

R.C.C. Wall

EQ

EQ

8 98

Stone Veneering

Mortar as Specified Face Joints not to be more than 1.5 mm

Mortar 10 mm Thick 80 mm or as Specified FRONT ELEVATION SECTION

Fig. 8.2C :Typical Details of Cramps for R.C.C. Backing

Drawing not to scale All dimensions in mm

Fig. 8.2 : Marble Stone Veneering (Typical Fixing Arrangement)

CPWD SPECIFICATIONS 2009

288

GENERAL ARRANGEMENTS OF CRAMPS Sub Head : Marble Work Clause : 8.6.2.3

A

D

G

B

C

E

F

H

Note : Cramps arrangement is shown above for veneerings with longer sides vertical. For veneerings having the longer sides horizontal cramps would be arranged to suit the altered positions.

Drawing not to Scale

Fig. 8.3 : General Arrangements of Cramps

289

SUB HEAD 8.0 : MARBLE WORK

MARBLE SLAB URINAL PARTITION Sub Head : Marble Work Clause : 8.7

Shape as per requirement

450 above Ground Level or upto Ground Level as Directed

75

Drawing not to scale All dimensions are in mm

Fig. 8.4 : Marble Slab Urinal Partition

CPWD SPECIFICATIONS 2009

290

SUB HEAD : 9.0

WOOD WORK AND P.V.C. WORK

CONTENTS Clause No.

Brief Description List of Mandatory Tests

Page No. 297

List of Bureau of Indian Standard Codes

298

9.0

Terminology

300

9.1

Timber

301

9.2

Panelling Material

304

9.3

Door, Window and Ventilator Frames

314

9.4

False Ceiling and Partition Frames

315

9.5

Trusses

315

9.6

Panelled Glazed or Panelled and Glazed Shutters

316

9.7

Flush Door Shutters

321

9.8

Wire Gauze Fly Proof Shutters

323

9.9

Wall Lining

324

9.10

Shelves

325

9.11

Trellis (Jaffri) Work

325

9.12

Pelmets

326

9.13

Hold Fasts

326

9.14

Expanded Metal, Hard Drawn Steel Wire Fabric and Wire Gauze in Wooden Frames

326

9.15

Fittings

327

9.16

Laminated Veneer Lumber (LVL)

340

9.17

Partitions

345

9.18

UPVC Door Frames

346

9.19

PVC Door Shutters

347

9.20

PVC Door Frame

349

9.21

Panel PVC Door Shutter

349

293

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

9.22

Fibre Glass Reinforced Plastic (FRP) Door Frames

350

9.23

Fibre Glass Reinforced Plastic (FRP) Shutters

351

9.24

Solid PVC Foam Profile Doors

351

9.25

Solid PVC Foam Shutters

352

9.26

Factory Made Fibre Glass Reinforced Plastic Chajja

353

9.27

Wall Panelling

353

Appendix A

Permissible Defects for Various Grade of Timbers

354

Appendix B

Different Climatic Zones for Moisture Content of Timber

355

Appendix C

Moisture Content of Timber

356

Appendix D

Physical and Mechanical Properties of Plywood

357

Appendix E

Physical and Mechanical Properties of FPT or Graded Particle Board.

357

Appendix F

Test for Flush Door Shutters

358

Appendix G

Test for Mortice Locks

360

Appendix H

Schedule of Fitting for Doors and Windows

361

Appendix I

Method of Test for Edge Straightness and Squareness of Plywood

362

Appendix J

Method of Test for Edge Straightness and Squareness of Coir Veneer Board

362

Appendix K

Method for Test of Coir Veneer Board for Determination of Glue Shear Strength

363

Fig. 9.1

Joints in Timber

365

Fig. 9.2

Terminology Timber Door, Window and Ventilator Components

366

Fig. 9.3

Wooden Flush Door Shutters

367

Fig. 9.4

Hold Fast

368

Fig. 9.5 to 9.6

Hinges

369

Fig. 9.7

Sliding Door Bolts

371

Fig. 9.8

Barrel Tower Bolts

372

Fig. 9.9

Pull Bolt Locks

373

CPWD SPECIFICATIONS 2009

294

Fig. 9.10

Mortice Lock & Latch

374

Fig. 9.11

Mortice Night Latch

375

Fig. 9.12

Handles for Doors & Windows

376

Fig. 9.13

Floor Door Stopper – Cast Type

378

Fig. 9.14

Window Stay & Hooks & Eyes

378

Fig. 9.15

Hasps & Staples

379

Fig. 9.16

LVL Shutter

380

Fig. 9.17

Partitions

381

Fig. 9.18

UPVC Door Frame

382

Fig. 9.19

24 mm Thick PVC Door Shutters

383

Fig. 9.20

30 mm Thick PVC Door Shutters

384

Fig. 9.21

PVC Door Frame

385

Fig. 9.22

30 mm Thick Panel PVC Door Shutter

386

Fig. 9.23

FRP Door Frame

387

Fig. 9.24

Typical Sketch of FRP Door Shutter

388

Fig. 9.25

Solid PVC Foam Profile Shutter

390

Fig. 9.26

Solid PVC Foam Shutter (28 mm Thick)

391

Fig. 9.27

FRP Chajja

392

Fig. 9.28

Wall Panelling

392

295

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

CPWD SPECIFICATIONS 2009

296

LIST OF MANDATORY TESTS Material

Clause

1 Timber

2 9.1.6

Flush door

9.7.10

Mortice Locks

9.15.13

Frequency Min, Quantity of of Testing Material for carrying out the test 3 4 5 6 7 Every one Moisture Field (by Appendix ‘C’ 1 cum cum or part content moisture meter) thereof. laboratory test as required by Engineer-inCharge End immersion Laboratory IS 2202 26 shutters As per Test knife test Appendix ‘F’ sampling Adhesion Test and testing specified in clause 9.7.11 Testing of Laboratory IS 220950 Nos 100 or part spring Appendix ‘G’ thereof. Test

Field/ Laboratory Test

297

Test Procedure

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

LIST OF BUREAU OF INDIAN STANDARD CODES S. No. 1. 2. 3. 4. 5. 6. 7. 8.

IS No.

Subject

IS 204 (Part I) IS 204 (Part II) IS 205 IS 206 IS 207 IS 208 IS 281 IS 287

9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22.

IS 303 IS 362 IS 363 IS 364 IS 401 IS 419 IS 451 IS 452 IS 453 IS 707 IS 710 IS 723 IS 729 IS 848

23.

IS 851

24. 25. 26.

IS 852 IS 1003 (Part I) IS 1003 (Part II)

27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37.

IS 1141 IS 1200 Part XIV IS 1200 Part XII IS 1328 IS 1341 IS 1378 IS 1566 IS 1568 IS 1658 IS 1659 IS 1708 (Part 1 to 18) IS 1734 IS 1823 IS 1868 IS 2046 IS 2095

Specification for tower bolts (ferrous bolt) Specification for tower bolts (non ferrous metals) Specification for non ferrous metal butt hinges Specification for Tee and strap hinges Specification for Gate and shutter hook and eye Specification for door handles Specification for mild steel door bolts for use with pad locks Recommendations for maximum permissible moisture contents of timber used for different purpose Specification for plywood for general purposes Specification for parliament hinges Specification for hasps and stapple Specification for fan light catch Code of practice for preservation of timber Putty for use on window frames Technical supply condition for wood screws Specification for door spring rat tail type Specification for double acting spring hinge Glossary of terms applicable to timber technology and utilization Specifications for Marine Plywood Specification for steel counter sunk head wire nails. Specification for drawer lock, cup board lock and box locks Specification for synthetic resin adhesive for plywood (phenoic and amino plastic) Specification for synthetic resin adhesive for const. work (non structural in wood) Specification for animal glue for general wood work purpose Specification for timber panelled and glazed shutter Part I (door shutters) Specification for timber panelled and glazed shutter Part II (window and ventilator shutter) Specification for code of practice for seasoning of timber Method of measurement of building and civil engg work glazing. Wood work and joinery Specification for veneered decorative plywood Specification for steel butt hinges Specification for oxidized copper finishes Specification for hard drawn steel wire fabric Specification for wire cloth for general purpose Specification for hard drawn steel wire fabric Specification for block boards Testing of small clear specimen for timber

38. 39. 40. 41. 42.

CPWD SPECIFICATIONS 2009

Determination of density and moisture content. Specification for floor door stopper Specification for anodic coating on aluminium and its alloy -do- Decorative thermosetting synthetic resin bonded laminated sheet Specification for gypsum plaster board

298

43. 44.

IS 2096 IS 2202 (Pt I)

45. 46. 47.

IS 2202 (Part II ) IS 2209 IS 2380

48. 49.

IS 2547 IS 2753

50. 51.

IS 2681 IS 3087

52. 53 54 55. 56. 57. 58. 59. 60 61. 62. 63. 64. 65. 66 67. 68. 69. 70. 71. 72. 73. 74. 75. 76. 77. 78. 79. 80. 81. 82. 83. 84. 85.

IS 3097 IS 3828 IS 3400 (Part II) IS 3400 (Part IV) IS 3400 (Part IX) IS 3564 IS 3618 IS 3813 IS 3818 IS 3847 IS 4835 IS 4948 IS 4992 IS 5187 IS 5509 IS 5930 IS 6318 IS 6607 IS 6760 IS 7196 IS 7534 IS 7638 IS 8756 IS 9308 (Part II) IS 9308 (Part III) IS 11215 IS 12049 IS 12406 IS 12817 IS 12823 IS 14616 IS 14842 IS 14856 IS 14900

Specification for asbestos cement flat sheet. Specification for wooden flush door shutter, solid core type (plywood face panels ) -do- (Particle boards and hard board face panels) Specification for mortice lock (Vertical Type ) Method of test for wood particle board and board for lignocelluloses material Specification for gypsum plaster Method for estimation of preservatives in treated timber and in treating solutions. Specification for non-ferrous metal sliding door bolts use with pad locks Specification for wood particle boards (Medium density) for general purpose. Specification for veneered particle board Specification for ventilator chain Method of test for Vulcanized rubber (hardness) Accelerated aging Density Specification for door closer (hydraulically regulated) Phosphate treatment of iron and steel for protection against corrosion “C” hooks for use with swivels Specification for continuous (Piano) hinges Specification for mortice night latch Specification for polyvinyl acetate dispersion based adhesive for wood Specification for welded steel wire fabric for general use Specification for rebated mortice lock Specification for flush bolts Specification for Fire Retardant Plywood Specification for mortice latch Specification for plastic wire window fastners Specification for rebated mortice lock (Vertical type) Specification for sloted counter sunk head wood screws. Specification for hold fast Specification for sliding locking bolts for use with pad lock Wood/lignocellulosic based panel products – Method for sampling Specification for mortice ball catch for use in wooden almirah Specification for mechanically extracted coir fibres. (Mattress coir fibres) -do- Decorated coir fibre Moisture content of timber and timber products method of determination Dimensions and tolerance relating to wood based panel materials Specification for medium density fibre board Specification for stainless steel Butt Hinges Specification for wood products –Prelaminated particle Boards Specifications for laminated veneer lumber Specification for coir veneer board for general purposes Specification for glass fibre reinforced plastic (FRP) panel type door Specifications for transparent float glass

299

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

9.0 WOOD WORK AND P.V.C. WORK 9.0 TERMINOLOGY Ballies : Thin round poles usually without bark. Beam : A structural timber generally long in proportion to its width and thickness and used for supporting load primarily by its internal resistance to bending. Block Board : A Board having a core made up of strips of wood, each not exceeding 25 mm in width, laid separately or glued or otherwise joined to form a slab which is glued between two or more outer veneers with the direction of the grain of the core blocks running at right angles to that of the adjacent outer veneers. Core : The inner layers of a composite wood product. Cross Band : A general term indicating a transverse layer of veneer or veneers in composite wood products. Decorative Veneers : Veneers having attractive appearance due to figure, colour, grain, lusture, etc. Hard Wood : A conventional term used to denote the wood obtained from broad-leaved trees. It has no relationship to the physical properties of hardness or strength. On account of the confusion this word might cause, its use is discouraged. Freeze Rail : Horizontal member, mortised or otherwise secured to the stiles of a door, provided just below the freeze panel usually provided for decorative purposes in the uppermost portion of the door. Joint : A prepared connection for joining adjacent pieces of wood, veneer, etc. Dovetail Joint : A joint at the corner of two pieces in such a way that the notches made to one are fitted exactly into projections of corresponding size and shape made in the other. There are various kinds of dovetail joints for instance, lapped dovetail joint, wedge shaped dovetail joint, etc. joined in a way which will resist withdrawal except in the direction in which it was assembled (Fig. 9.1C). Mitred Joint : A joint, between two members at an angle which bisects the joining angle usually the joining faces are cut at 45° to form a right angle (Fig. 9.1B). Mortise and Tenon Joint : A joint in which the reduced end (tenon) of one member fits into the corresponding slot (mortise) in another member (Fig. 9.1D). Tongue and Groove Joint : A joint in which a tongue is provided on edge of one member to fit into a corresponding groove on the other (Fig. 9.1A). Knot : Base of a branch or limb embedded in the tree which becomes visible when it is cut. Diameter of a Knot : The maximum distance between two points farthest apart on the periphery of a round knot, on the face where it becomes visible. In the case of a spike or splay knot, the maximum width of the knot visible on the face on which it appears shall be taken as its diameter. Muntin : Small horizontal or vertical dividing bars within basic framework of a window, or door subdividing and supporting the glass panes or panels of doors. CPWD SPECIFICATIONS 2009

300

Particle Board : A board manufactured from particles of wood or other lignocellulose material, for example, flakes, granules, shavings, slivers, splinter agglomerated, formed and pressed together by use of an organic binder together with one or more of the agents, such as heat, pressure, moisture and a catalyst. Particle : Distinct particle or fraction of wood, or other lignocellulose material produced mechanically for use as the aggregate for making a particle board. This may be in the form of flake, granule, shaving, splinter and sliver. Plywood : A board formed of three or more layers of veneers cemented or glued together, usually with the grain of adjacent veneers running at right angles to each other. Rebate : A recess along the edge of a piece of timber to receive another piece or a door, sash or a frame. Sapwood : The outer layers of the log, which in the growing tree contain living cells and feed material. The sapwood is usually lighter in colour, and is readily attacked by insects and fungi. Seasoning : A process involving the reduction of moisture content in timber under more or less controlled conditions towards or to an amount suitable for the purpose for which it is to be used. Seasoned Timber : Timber whose moisture content has been reduced to the specified minimum, under more or less controlled processes of drying. Structural Timber : Timber used in framing and load bearing structures or timber used or intended for use in buildings where strength is the primary consideration. First Class Wood Individual hard and sound knots shall not be more than 25 mm in diameter and the aggregate area of all the knots shall not exceed one per cent of the area of the piece. Second Class Wood Individual hard and sound knot shall not be more than 40 mm in diameter and aggregate of all the knots shall not exceed one and half per cent of the area of the piece. Wood shall be generally free from sapwood, but traces of sapwood may be allowed. 9.1 TIMBER Timber is classified as under : (i) Teak wood (ii) Deodar wood (iii) Non-coniferous timbers other than teak (iv) Coniferous timber other than deodar. The timber shall be free from decay, fungal growth, boxed heart, pitch pockets or streaks on the exposed edges, splits and cracks. The timber shall be graded as first grade and second grade on the basis of the permissible defects in the timber as given in Appendix ‘A’ of Chapter 9.0. For both the grades, knots should be avoided over a specified limit. 9.1.1 Teak Wood (Tectona Grandis) It is of outstanding merit in retention of shape and durability. The heart wood is one of the most naturally durable woods of the world. It usually remains immune to white ant attack and insect attack for very long periods. It is, however, not always immune from fungus attack (rot). Taken as a whole, good quality teak is very durable, it is relatively easy to saw and work. It can be furnished to a fare surface and takes polish well. It is generally used for making furniture and all important timber construction. 301

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

9.1.1.1 Superior Class Teak Wood such as Balarsha, Malabar and Dandeli : Individual hard and sound knot shall not be more than 12 mm in diameter and the aggregate area of all the knots shall not exceed one half per cent of the area of the piece. It shall be close grained. 9.1.2 Deodar Wood (Cedrus Deodars) It is the strongest of the Indian conifers. Its weight and strength is 20% per cent less than teak. It is easy to saw and works to a smooth finish. It is not, however, a suitable wood for polish or paint work as the oil in the wood and especially near knots, always seeps through such finishes and discolours them. It is used for house building, furniture and other construction work. It is also suitable for beams, floors, boards, posts, window frames and light furniture etc. 9.1.3 Sal Wood (Shoera Robusta) Sal is about 30 per cent heavier than teak, 50 per cent harder, and about 20 to 30 per cent stronger. In shock resistance it is about 45 per cent above teak. Its heart wood is a naturally durable wood, and usually remains immune to attack by white ants and fungi for a long period, while its sapwood is very perishable and should not be used. Well dried sal is not a really easy wood to saw and work. It is a rough constructional wood than a carpentary timber. No individual hard and sound knot shall exceed 25 mm in diameter and the aggregate area of all the knots shall not exceed 1% of the area of the piece. It can be used for a variety of purposes, such as for beams, rafters, flooring, piles, bridging, tool handles, picker arms and tent pegs, etc. 9.1.4 Kail Wood (Pinus Roxburghie) Kail Wood is not a very durable wood. But it is easy to saw and work and usually very popular in wokshops. It can be brought to a fine smooth surface, but is more suitable for paint and enamel finishes than for polish work. It is useful for joinery works, constructional work, light furniture and house fitments. 9.1.5 Other Species The other species of timber as given in Table 9.1 of chapter 9.0 can also be used for various activities of building construction. TABLE 9.1 Species of Timber Availability Sl. Botanical Name Trade Average Unit North East Central West South Zone Zone Zone Zone Zone No. Name wt Kg/m3 1. Tectone grandis linnf Teak 640 — Y X X X 2. Acacia Catechiu Willd Khair 1010 X X X Y Y 3. Acacia Arabica Willd Babul 785 X X X Y Z 4. Adina Cordifolia Roxb HK. f Haldu 675 X — — — X 5. Cedrus Deodara D Don Deodar 545 X — Y Y — 6. Magnifera Indica Linn Mango 690 X X Y X 7. Pinus Roxburghie Chir 575 X — — — — 8. Pinus Excelsa Wall Kail 515 X — — — — 9. Shorea Robusta Gaertn. Sal (U.P.) 881 X X X — — 10. Terminalia Myrioecarpa Heurcket Muell Arg. Hollock 610 — X — — — 11. Lagerstroemia Lanceolata Benteak 675 — — — Y X Wall 12. Gamelinc Arborea Ronb. Gamari 515 Y Y Y Z Y 13. Terminalia Bellirica Roxb. Bahora 801 X X X Y X 14. Pterocarpus Marsupium Bijasal 800 — X X Y Y Roxb Note : The Average unit wt. is at 12% moisture content. CPWD SPECIFICATIONS 2009

302

NORTH ZONE

:

EAST ZONE

:

CENTRAL ZONE

:

WEST ZONE

:

SOUTH ZONE

:

Jammu and Kashmir, Punjab, Himachal Pradesh, Delhi, Uttar Pradesh and Rajasthan. Assam, Manipur, Tripura, West Bengal, Bihar, Orissa, Sikkim, Andamans, North East Frontier Agency and Nagaland. Madhya Pradesh, Vidharbha areas of Maharashtra State and the North East Part of Andhra Pradesh (Godavari delta area). Maharashtra State (Except Vidharbha areas), Gujarat and North West part of Karnataka. Tamil Nadu, Andhra Pradesh (except the Godawari Delta area) Kerala and karnataka (except north west port) Tamil Nadu, Andhra Pradesh (Except the Godawari delta area) Kerala and Karnataka (except North West part)

The availability of timbers is categorised under three classes as indicated below: X - Most common, 1415 m3 (1000 tonnes) and more per year. Y - Common, 355 m3 (250 tonnes) to 1415 m3 (1000 tonnes) per year and Z - Less common, below 355 m3 (250 tonnes) per year. 9.1.6 Moisture Content Control on moisture content of timber is necessary to ensure its proper utility in various climatic conditions. For specifying the permissible limit of moisture content in the timber the country has been divided into four climatic zones as per Appendix B of Chapter 9. In each of the zones, maximum permissible limit of moisture content of timber for different uses, when determined in accordance with the procedure laid down in Appendix ‘C’ shall be as per Table 9.2 of Chapter 9. TABLE 9.2 Maximum Permissible Moisture Content of Timber Sl.No.

1. 2.

3. 4.

Use

Beams, Rafters & Posts Doors and windows (a) 50 mm and above thickness (b) Thinner than 50 mm Flooring strips Furniture & Cabinet making

Zone I 12 10 8 8 10

Max Moisture Content Percent Zone Zone Zone II III IV 14 17 20 12 10 10 12

14 12 10 14

16 14 12 15

9.1.6.1 Tolerance on Moisture Content : Average Moisture content of all the samples from a lot shall be within + 3 per cent and moisture content of individual samples within + 5 per cent of maximum permissible moisture content specified in Table 9.2. These tolerance are the absolute values over the percentage moisture content for Sl. No. 1 & 2 of Table 9.2. No tolerance on moisture content is permitted for Sl. No. 3 & 4 of Table 9.2. 9.1.7 Seasoning of Timber The process of drying timber under controlled conditions is called seasoning of timber. Timber shall be either air seasoned or kiln seasoned and in both cases moisture content of the seasoned timber shall be as specified in Table 9. 2 of Chapter 9 unless otherwise specified, air seasoned timber shall be used. Kiln seasoning of timber, where specified, shall be done as per IS 1141 in a plant approved by Engineerin-Charge.

303

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

9.1.8 Preservation of Timber Preservative treatment does not improve basic properties of timber but gives varying degree of protection against deterioration due to attacks by fungi, termites, borers and marine organisms. Preservative treatment, where specified, shall be done using Oil type, Organic solvent type or Water-soluble type preservative. Oil type preservatives shall be used if the timber is not required to be polished or painted. Before preservative treatment, the timber shall be sawn and seasoned. All surfaces exposed after treatment, except due to planing, shall be thoroughly brushed with the preservation before jointing. Preservative treatment of timber shall be done as per IS 401 in a plant approved by the Engineer-in-Charge. 9.2 PANELLING MATERIAL 9.2.1 Timber Timber panels shall be preferably made of timber of larger width. The minimum width and thickness of a panel shall be 150 mm and 15 mm respectively. When made from more than one piece, the pieces shall be joined with a continuous tongue and groove joint, glued together and reinforced with metal dowels. The grains of timber panels shall run along the longer dimensions of the panels. The panels shall be designed such that no single panel exceeds 0.5 square metre in area. 9.2.2 Plywood /Plywood Boards 9.2.2.1 Plywood boards are formed by gluing and pressing three or more layers of veneers with the grains of adjacent veneers running at right angles to each other. The veneers shall be either rotary cut or sliced and shall be sufficiently smooth to permit an even spread of glue. Face veneers may be either decorative on both sides or one side commercial and the other decorative. Plywood shall be of BWP grade or BWR grade as per IS 303. 9.2.2.2 Adhesive : Adhesive used for bonding BWP grade of plywood boards shall be BWP type synthetic resins conforming to IS 848 . 9.2.2.3 The thickness of all veneers shall be uniform, within a tolerance of ± 5 per cent. Corresponding veneers on either side of the centre one shall be of the same thickness and species. The requirements of thickness and core veneers shall be as follows: (a) In 3 ply boards upto 5 mm thick. The combined thickness of the face veneers shall not exceed twice the thickness of centre ply. (b) In multiply boards, the thickness of any veneer shall not be more than thrice the thickness of any other veneer. (c) The sum of the thickness of the veneers in one direction shall approximate to the sum of the thickness of the veneers at right angle to them and shall not be greater than 1.5 times this sum except for 3 ply as specified in (a). 9.2.2.4 Thickness :Plywood boards are available in thickness ranging from 3 to 25 mm. Tolerance in thickness shall be ± 10% for boards upto and including 5 mm; ± 7% for boards from 6 to 9 mm and ± 5% for boards above 9 mm thickness. The boards shall be of uniform thickness and the surfaces of the boards shall be sanded to a smooth finish. Number of plys in plywood boards shall be as per Table 9.3. TABLE 9. 3 Thickness in mm

No. of ply

Thickness in mm

3,4,5,6 5,6,8,9 9,12,15,16

3 5 7

12,15,16,19 19,22,25

Note : Plywood of 9 mm thick of 5 or 7 ply may be used generally. CPWD SPECIFICATIONS 2009

304

No. of ply 9 11 (Above 11 Ply as ordered)

9.2.2.5 Moisture content of the plywood boards when tested in accordance with IS 1734 (Part 1) shall not be less than 5 per cent and not more than 15 per cent. 9.2.2.6 Testing : One sample for every 100 sqm or part thereof shall be taken and testing done as per IS 303. However, testing may not be done if the total requirement of plywood boards is less than 30 sqm. All the samples tested shall meet the requirements of physical and mechanical properties of plywood boards specified in Appendix D of Chapter 9. 9.2.3 Particle Boards 9.2.3.1 Particle boards shall be of medium density and manufactured from particles of agro waste, wood or lignocellulose i.e. material blended with adhesive and formed into solid panels under the influence of heat, moisture, pressure etc. The particle boards shall be flat pressed three layered or graded and of Grade-I as per Table 1 of IS 3087. Both surfaces of the boards shall be sanded to obtain a smooth finish and shall conform to IS 3087. 9.2.3.2 Adhesives : Adhesives used for bonding shall be BWP type synthetic resin conforming to IS 848. 9.2.3.3 Thickness and Tolerance : Thickness of particle boards shall be as specified. Tolerance in thickness shall be ± 5% for boards upto and including 25 mm thick and ± 2.5 per cent for boards above 25 mm thickness. Each board shall be of uniform thickness. 9.2.3.4 Testing : One sample for every 100 sqm or part thereof shall be taken and testing done as per IS 3087. However, testing may not be done if the total requirement of particle boards in a work is less than 30 sqm. All the samples tested shall meet the requirement of physical and mechanical properties of particle boards specified in Appendix E of Chapter 9.0. 9.2.4 Veneered Particle Boards 9.2.4.1 Veneered Particle Boards with core of FPT-1 or graded board Grade-I particle board (IS 3087) with commercial or general purpose veneer (Type-1) or decorative veneers on both faces or with decorative veneer on one face and commercial /general purpose veneers on the other Type-2. Face veneers are bonded using adhesives under the influence of heat and pressure. 9.2.4.2 Adhesives : The adhesive used for bonding veneers shall be BWP or BWR type conforming to IS 848 for grade I veneered particle board. 9.2.4.3 Thickness & Tolerance : Veneered particle boards are available in various thickness 6, 10, 12, 20, 25, 30, 35, 40, 45 & 50 mm. Tolerance in thickness shall be ± 5%. 9.2.4.4 Testing : One sample for every 100 sqm or part thereof shall be taken and testing done as per IS 3097. However, testing may not be done if the total requirement of veneered particle boards in a work is less than 30 sqm. All the samples tested shall meet the requirements of physical and mechanical properties of veneered particle boards as under:

305

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

1. 2.

3. 4.

5.

Moisture Content Water Absorption (a) 2 hrs. soaking (b) 24 hrs. soaking Water Resistance

5-15% Not more than 25% Not more than 50% No sign of disintegration or delamination after 3 hrs. boiling in water.

Swelling in Water (a) General absorption for 2 hrs. immersion (b) Surface absorption for 2 hrs. Adhesion of plies

Not more than 7% Not more than 5% Knife test

9.2.4.5 Type of face veneers, thickness of veneered particle boards and adhesive used for bonding shall be as specified. Unless otherwise stated, exterior grade veneered particle boards with BWP type synthetic resin adhesive shall be used. 9.2.5 Non-Asbestos Fibre Boards 9.2.5.1 Fibre boards shall be of medium density cement board reinforced with wood fibre, produced by fiberizing steamed wood under pressure, blended with adhesive and wax and formed into solid panels under controlled conditions of heat and pressure as per IS 14862. 9.2.5.2 Adhesives : The adhesive used for bonding shall be BWP type synthetic resin conforming to IS 848. 9.2.5.3 Thickness : Fibre boards are available in thickness 6, 9, 12, 15, 18, 22, 25, 30, 35 & 40 mm. The tolerance in thickness shall be ± 0.3 mm. Thickness of fibre boards and adhesive used for bonding shall be as specified. Unless otherwise stated, exterior grade fibre boards bonded with BWP type synthetic resin adhesive shall be used. 9.2.6 Float Glass, Frosted Glass Float glass used shall be as specified in sub-head 21.0 of this specifications. For panel exceeding 0.5 sqm in area, the nominal thickness of the glass to be used shall be as specified. 9.2.7 Wire Cloth (Wire Gauze) 9.2.7.1 Wire Cloth which shall generally conform to IS 1568 shall be regularly woven with equally spaced galvanised mild steel wires in both warp and weft directions. The wire cloth shall be properly selvedged by one or more wires in each edge. 9.2.7.2 Mesh : Average width of aperture and the nominal diameter of the wire shall be as under: Average width of Aperture mm 1.40 1.18 1.00

Nominal dia. of wire mm 0.63 0.56 0.50

9.2.7.3 Width of aperture and dia of wire cloth shall be as specified. Unless otherwise stated, wire cloth of 1.40 mm average aperture width woven with 0.63 mm nominal dia galvanised mild steel wire shall be used. CPWD SPECIFICATIONS 2009

306

9.2.7.4 Fly-proof wire cloth (aperture 1.40 mm) is generally provided in Kitchen and dining areas while wire cloth of smaller aperture is used in mosquito proof shutters. 9.2.8 Veneered Decorative Plywood Decorative plywood shall be of two grades namely BWR and MR Decorative Plywood shall be of two types. Type I and type 2 and shall conform to IS 1328. 9.2.8.1 Requirement of Type-I Veneered decorative plywood shall be as under: (a) Open slits checks or open joints not more than 150 mm in length and 0.5 mm in width shall be permissible provided the same are rectified with a veneer insert bounded with synthetic resin adhesive, as the case may be and further provided that the insert matches with the surrounding veneer in colour as well as figure. (b) The decorative veneered surface shall be free from torn grain, dead knots discolourisation and sapwood. (c) The decorative veneered surface shall be selected for figure, texture, colour and grain etc. It shall be free from all manufacturing and wood defects except to the Engineer-in-charge permitted under para 9.2.8.1(a). All veneers shall be matched or mismatched to achieve a decorative effect in colour figure and grain. 9.2.8.2 Adhesive : The adhesive for bonding veneers shall be MR and BWR type synthetic resin adhesive conforming to IS 848 for MR and BWR grade veneered decorative plywood respectively. 9.2.8.3 Dimensions and Tolerances: 9.2.8.3.1 The dimensions of plywood boards shall be as follows: 2400 mm x 1200 mm 2100 mm x 900 mm 2100 mm x 1200 mm 1800 mm x 900 mm 1800 mm x 1200 mm 9.2.8.3.2 Thickness: The thickness of plywood board shall be 3 mm, 4 mm, 6 mm, 9 mm, 12 mm, 19 mm and 25 mm. Note: Any other dimensions (length, width and thickness) as agreed to between the manufacturer and the purchaser may also be used. 9.2.8.3.3 Tolerances: Tolerances on the nominal sizes of finished boards shall be as follows: Dimension Tolerance Length +6 mm -0 Width +3 mm -0 mm Thickness: (i) Less than 6 mm (ii) 6 mm and above Edge straightness Squareness

+ 10 per cent + 5 per cent 2 mm per 1000 mm Or 0.2 per cent 2 mm per 1000 mm Or 0.2 per cent

Note : Edge straightness and squareness shall be tested as per Appendix I. 307

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

9.2.8.4 Finish : The decorative plywood shall be uniform in thickness within the tolerances limits specified. The ends shall be trimmed straight and square edge straightness and squareness when tested as per Appendix I shall be within the tolerance specified in 9.2.8.3.3. 9.2.8.5 Sampling and Criteria for Conformity : The method for drawing representative samples and criteria for conformity shall be as per IS 7638. 9.2.8.6 Tests : Boards shall be subjected to following tests : (i) Moisture content: Decorative veneered plywood of either type when tested in accordance with IS 1734 (Pt. I) shall have a moisture content not less than 5 per cent and not more than 15 per cent. (ii) Water Resistance Test : Three test specimen of size 250 mm x 100 mm shall be prepared for each of the boards selected and submerged in water at 62 +2o C for a period of 3 hours and dried for 8 hours at a temperature of 65 + 2oC and then followed by two more cycles of soaking and drying under same conditions described above. Decorative Veneered plywood of either type shall not show delamination or blister formation. 9.2.8.7 Marking : Each plywood bound shall be legibly and indelibly marked or stamped with the following on the face of board near one corner. (a) Indication of the source of manufacture (b) Year of manufacture (c) Batch no. (d) Type of plywood (e) Criteria for which the plywood has been lablled as ECO mark The decorative veneered plywood may also be marked with standard BIS certification mark. 9.2.9 Prelaminated Particle Boards 9.2.9.1 Prelaminated particle boards are available in two grades namely Grade I and II as per IS 12823. Each grade is further classified in four types; namely Type –I, II, III, IV. 9.2.9.2 Material 9.2.9.2.1 Particle Board Prelaminated particle board Grade-1 (FPT–I or graded wood particle board FPT-I) bonded with BWP type synthetic resin and prelaminated conforming to IS 12823 Grade-I, type II or I shall be used. 9.2.9.2.2 Impregnated Base Paper : Printed or plain coloured absorbent base paper having a weight of 60-140 g/m2 impregnated in a suitable synthetic resin and dried to a volatile content of 4-8 per cent shall be used for prelamination on both surfaces of particle board. 9.2.9.2.3 Impregnant Overlay : An absorbent tissue paper having a weight of 18-40 g/m2 impregnated in a suitable synthetic resin and dried to volatile content of 4-8 per cent. 9.2.9.3 Dimension and Tolerances 9.2.9.3.1 Dimensions of prelaminated particle boards shall be as follows: Length : The length of prelaminated particle boards shall be 4.8, 3.6, 3.0, 2.7, 2.4, 2.1, 1.8, 1.5, 1.2, 1.0 and 0.9 metres. Width : The width of prelaminated particle boards shall 1.8, 1.5, 1.2, 1.0, 0.9, 0.6 and 0.45 metres.

CPWD SPECIFICATIONS 2009

308

Thickness

:

The thickness of prelaminated particle boards shall be 6, 9, 12, 15, 20, 25, 30, 35, 40 and 45 mm.

9.2.9.3.2 Tolerances : Tolerances on the nominal sizes of finished boards shall be as given below : Dimension Tolerance Length + 6 mm -0 Width + 3 mm -0 Thickness 5 per cent Edge straightness 2 mm per 1000 mm or 0.2 per cent Squareness 2 mm per 1000 mm or 0.2 per cent Note : Edge straightness and squareness shall be tested as per IS 12823. 9.2.9.4 Sampling and Inspection : The number of prelaminated particle board to be selected from a lot shall be in accordance with the Table 9.4 given below: TABLE 9.4 Lot Size Upto 50 51 to 100 101 to 200 201 to 300 301 to 500 501 and above

Number of prelaminated boards to be selected 2 3 4 5 7 10

9.2.9.4.1 The prelaminated particle boards shall be selected at random (ref. IS 4903). In order to ensure randomness of selection, all the prelaminated particle boards in the lot may be arranged in a serial order and every rth prelaminated particle board may be selected till the required number is obtained, ‘r’ being the integral part of N/n, where N is the lot size and n is the sample size. 9.2.9.4.2 All board selected as given in para 9.2.9.4.1 shall be tested as specified in IS 2380 (part-2) for length, width, thickness, edge straightness and squareness shall comply with the requirements specified under para 9.2.9.3.2. 9.2.9.5 Testing and Number of Tests : For each of particle board selected as per para 9.2.9.4 Test specimens shall be cut out from portion 150 mm away from the edges for tests and tests shall be carried out as per IS 12823. 9.2.9.6 Criteria for Conformity: A lot shall be considered as in conformity to the requirements of the specification if no group of specimens for any of the characteristics fails to meet the conditions as prescribed in para 9.2.9.3 & 9.2.9.5 of this specification. In case of a failure, double sample shall be taken from the lot for testing. The lot shall be considered as passed, if all these samples conform to the specified requirement. 9.2.9.7 Marking : Each prelaminated particle board shall be legibly and indelibly marked on any of its edges with following : (a) Indication of source of manufacturer

309

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

(b) Grade and type of prelaminated particle board (c) Thickness (d) Batch number and year of manufacture 9.2.10 Coir Veneer Board for General Purposes 9.2.10.1 Coir veneer board is manufactured with a combination of coconut fibre needled felt, veneer and jute fibres with kraft paper coconut fibre. Needled felt can be used as core crossbands or as outer skin formed with jute fibres and kraft paper. However, the composite ply should be a balanced construction on either side of central ply. The blended mass of glued fibres is laid to form a mat which is pre needled. 9.2.10.2 Coir veneer board generally shall conform to IS 14842. Grades Coir veneer board for general purposes shall be of two grades: (a) Boiling water resistant (BWR) grade (b) Moisture resistant (MR) grade 9.2.10.3 Material (a) Coconut Fibre : Coconut fibre layer used in the manufacture of coir veneer board shall be uniform with minimum of 600 g/m2. (b) Jute : Jute fibre layer used in the manufacture of coir veneer board shall be uniform with minimum of 60 g/m2. (c) Adhesive : Adhesive for manufacture of coir veneer board shall be conform to BWR/MR of IS 848 for BWR/MR grade boards respectively. (d) Veneer : Any species of timber may be used for the manufacture of veneers. (e) Kraft Paper : Kraft paper used in manufacture of coir veneer board shall be uniform with minimum of 40 g/m2 . 9.2.10.4 Permissible Defects : Gap in cores and crossband shall not be permitted. Splits in cores and crossbands may be permitted to an extent of 2 per core or crossband and overlap shall be permitted in core/crossbands only. 9.2.10.5 The Dimensions and Tolerances : The dimensions and tolerances of coir veneer board shall be quoted in following order. The first dimension shall represent the length, the second dimension the width and the third dimension the thickness. The dimensions and tolerances shall be as per IS 12049. Thickness of coir veneer board shall be 3 mm, 4 mm, 5 mm, 6 mm, 9 mm, 12 mm, 16 mm, 18 mm, 20 mm and 25 mm. The following tolerance on nominal thickness shall be permissible. (a) Less than 6 mm + 10% (b) 6 mm and above + 5% 9.2.10.6 Workmanship and Finish : Coir veneer board shall be of uniform thickness and density throughout the length and width of board. The squareness and edge straightness of the board shall be as per para 9 of IS 12842 and Appendix J.

CPWD SPECIFICATIONS 2009

310

9.2.10.7 Sampling : The method of drawing representative samples and criteria for conformity shall be as prescribed in IS 7638. 9.2.10.8 Tests : The tests shall be carried out as specified in IS 14842 – Appendix K. 9.2.10.9 Moisture Content : Coir veneer board when tested in accordance with IS 3734 (Part I) shall have a moisture content not less than 5 percent and not more than 15 percent. 9.2.10.10 Marking: Each coir veneer board shall be legibly and indelibly marked or stamped with the following near one corner. (a) Identification of source (b) Year of manufacturing (c) Batch no. (d) The grade and type as follows. (i) Boiling water resistant (BWR) and (ii) Moisture resistant (MR) 9.2.10.11 BIS Certification Marking : Coir veneer board may also be marked with the standard mark governed by the BIS Act, 1986. 9.2.11 Marine Plywood 9.2.11.1 Marine plywood shall be generally conforming to IS 710. Selection of timber species for manufacture of plywood shall be as prescribed in IS 710 and as far as possible a single species of timber shall be used. 9.2.11.2 Adhesive : The adhesive used for bonding the veneer shall be of the hot press synthetic resin, phenol formaldehyde type (BWP) and shall conform to IS 848. Extender shall not be added to the adhesive by the plywood manufactures. Fillers, if used, shall not exceed 10 percent by mass of solid content of the glue. 9.2.11.3 Dimensions 9.2.11.3.1 The dimensions of plywood boards shall be as stated in para 9.2.10.5. 9.2.11.3.2 The thickness of any board shall not exceed the number of pieces multiplied by 2.5 mm. The two face veneers in finished board shall be of the same nominal thickness. 9.2.11.4 Tolerances : The following tolerances in the nominal size of finished boards shall be permitted. Dimension Length Width Thickness

Nominal Size Upto 120 cm. Above 120 cm. Upto 90 cm. Above 90 cm Upto 4 mm Above 4 mm

Tolerance + 3 mm + 6 mm + 3 mm + 6 mm + 10 per cent + 5 per cent

9.2.11.5 Sampling : The method of drawing representative samples and criteria for conformity shall be as prescribed in IS 7638. 311

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

9.2.11.6 Tests : Test pieces cut from each of board as specified at para 9.2.11.5 shall be subjected to following tests. (a) Moisture content (b) Glue adhesive in dry state (c) Water resistance test. (d) Tensile strength (e) Mycological test (f) Retension of preservative. These tests shall be carried out as specified in IS 710. 9.2.11.7 Marking : Each plywood board shall be legibly and indelibly marked or stamped with following particulars along with such other marks as the purchaser may stipulate at the time of placing order. (a) Manufacturer’s name, initials or recognized trade mark, if any. (b) Year of manufacturing. (c) Abreviation indicating the species of timber used in each ply as indicated in col. 3 of Table – 1 and 2 of IS 710. (d) Batch number 9.2.11.8 BIS Certification Marking : The plywood board may also be marked with the standard mark, governed by the BIS Act,1986. 9.2.11.9 Tender Sample, Inspection and Acceptance: Where samples are required to be tendered, three samples each not less than 90 x 60 mm in size shall be submitted by the supplier, and these samples, if the tender is accepted shall constitute the standard as regards the type of timber, quality and finish. 9.2.12 Fire Retardant Plywood 9.2.12.1 Fire retardant plywood shall generally conform to IS 5509. The plywood to retardant treatment shall conform to BWR grade of IS 303 to be able to stand pressure Plywood for treatment shall be clean, free from oil or dirt patches on the surface and content not exceeding 15 percent. In case of veneered decorative plywood care shall colour of the solution does not spoil to decorative surface.

be given fire impregnation. at a moisture be taken that

For Eco-mark the plywood shall conform to the requirements of Eco-mark specified in IS 303. 9.2.12.2 Fire Retardant Treatment : This shall be either pressure impregnation or soaking treatment as per IS 5509. 9.2.12.3 Choice of Treatment : The choice of treatment may be left to the manufacturer of plywood as per fire resistant requirements prescribed in IS 5509. The purchaser should however, specify whether plywood is to be treated with fire retardants only or with fire retardants and preservatives. The recommended retention of fire retardant chemicals for different hazards like interior or exterior use not subject to leaching by rain and water is of the order of 50 kg/m3. 9.2.12.4 Conditioning after Treatment : The plywood after treatment shall be conditioned to suitable equilibrium moisture content of not more than 20 per cent. 9.2.12.5 Dimension and Tolerances shall conform to IS 2049. The tolerance of thickness shall conform to IS 303. CPWD SPECIFICATIONS 2009

312

9.2.12.6 Sampling : The method of drawing representative sample and the criteria of conformity shall be as prescribed in IS 7638. 9.2.12.7 Test Specimen and Number of Tests: From each of fire retardant plywood selected as above para 9.2.12.6, following test specimens shall be cut from portions 150 mm away from the edges for tests specified as under: (a) For Flammability : Six test specimens 125 mm x 125 mm in full thickness of material from each sample. (b) For Flame Penetration : Three test specimens 125 mm x 125 mm in full thickness of material from each sample. (c) For Rate of Burning : Three test specimen 100 mm x 12.5 mm in full thickness of material from each sample. 9.2.12.8 Test Requirements and Other Tests (i) Moisture Content : Shall not exceed 20%. (ii) Flammability : When tested as per IS 1734, time taken for second ignition shall not be less than 30 minutes. (iii) Flame Penetration : When tested as per IS 1734, time taken for flame penetration shall not be less than 15 minutes for every 6 mm thickness. (iv) Rate of Burning : When tested as per IS 1734, the time taken to lose weight from 30 per cent to 70 per cent shall not be less than 20 minutes. 9.2.12.9 Marking : Each board shall be legibly and indelibly marked near the edge with the following: (a) Manufacturer’s name, his initials or his recognized trade mark, if any. (b) Year of manufacture (c) Type of treatment (d) Criteria for which the plywood has been labeled as ECO mark. 9.2.12.10 BIS Marking : Each board may also be marked with standard mark governed by the BIS Act, 1986. 9.2.13 Decorative Thermosetting Synthetic Resin Bonded Laminated Sheets 9.2.13.1 Scope : Decorative thermosetting synthetic resin bonded laminated sheets shall generally conform to IS 2046. This material is intended for interior use and is not intended for load bearing applications. 9.2.13.2 Terminology : For the purpose of this standard, the definition given under para 2 of IS 1998 shall apply. 9.2.13.3 Types : The material shall be of two types namely:(a) Type 1- Having only one side bearing decorative surface the other side being roughened or given an appropriate treatment to promote adhesion to the base. This type shall generally be used, unless specified otherwise. (b) Type 2- Having both sides bearing the decorative surface, the two sides may be different in colour or pattern or both. 9.2.13.4 Requirements (i) Appearance : The types of surface finish of decorative and reverse side, edge finish, colour and pattern shall be as agreed to between the purchaser and the supplier. The sheets shall be reasonably free from local deformation. Note : Since sheets may vary slightly in colour and appearance, it is recommended that sheets for any one scheme may be matched. 313

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(ii) Flatness : For nominal thickness 1.5 mm – when a sheet is tested for flatness in accordance with the method given in Appendix –C of IS 2046, the height above the flat surface at the edge of full manufactured and trimmed width shall nowhere exceed 150 mm. (iii) Tolerance to nominal thickness : The departure from nominal thickness of sheet at any point, shall not exceed the value given below: Nominal Thickness Tolerance Upto 1.5 mm + 0.25 mm (iv) Straightness of edges of rectangular finished panels, resistance to dry heat, resistance to boiling water, resistance to staining, gross breaking strength, packing and marking, sampling and criteria for conformity etc. shall be as per IS 2046. 9.3 DOOR, WINDOW AND VENTILATOR FRAMES 9.3.1 Timber for door, window and ventilators frames shall be as specified. Timber shall be sawn in the direction of the grains. All members of a frame shall be of the same species of timber and shall be straight without any warp or bow. Frames shall have smooth, well-planed (wrought) surfaces except the surfaces touching the walls, lintels, sill etc., which may be left clean sawn. Rebates, rounding or moulding shall be done before the members are jointed into frames. The depth of the rebate for housing the shutters shall be 15 mm, and the width of the rebates shall be equal to the thickness of the shutters. A tolerance of ± 2 mm shall be permitted in the specified finished dimensions of timber sections in frames. 9.3.2 Joints The Jamb posts shall be through tenoned in to the mortise of the transoms to the full thickness of the transoms and the thickness of the tenon shall be not less than 2.5 cm. The tenons shall closely fit into the mortise without any wedging or filling. The contact surface of tenon and mortise before putting together shall be glued with polyvinyl acetate dispersion based adhesive conforming to IS 4835 or adhesive conforming IS 851 and pinned with 10 mm dia hard wood dowels, or bamboo pins or star shaped metal pins. The joints shall be at right angles when checked from the inside surfaces of the respective members. The joints shall be pressed in position. Each assembled door frame shall be fitted with a temporary stretcher and a temporary diagonal brace on the rebated faces. 9.3.3 Fixing of Frames The frames shall be got approved by the Engineer-in-Charge before being painted, oiled or otherwise treated and before fixing in position. The surface of the frames abutting masonry or concrete and the portions of the frames embedded in floors shall be given a coating of coal tar. Frames shall be fixed to the abutting masonry or concrete with holdfasts or metallic fasteners as specified. After fixing, the jamb posts of the frames shall be plugged suitably and finished neat. Vertical members of the door frames shall be embedded in the floor for the full thickness of the floor finish and shall be suitably strutted and wedged in order to prevent warping during construction. A minimum of three hold fasts shall be fixed on each side of door and window frames one at centre point and other two at 30 cm from the top and bottom of the frames. In case of window and ventilator frames of less than 1 m in height two hold fasts shall be fixed on each side at quarter point of the frames. Hold fasts and metallic fasteners shall be measured and paid for separately. 9.3.4 Measurements Wood work wrought, framed and fixed shall be measured for finished dimension without any allowance for the wastage or for dimensions beyond specified dimension. However, in case of members having mouldings, roundings or rebates and members of circular or varying sections, finished dimensions shall be taken as the sides of the smallest square or rectangle from which such a section can be cut. Length of each member shall be measured over all to the nearest cm so as to include projection for tenons. Width and thickness shall be measured to the nearest mm and the quantity shall be worked out in unit of upto three places of decimal. CPWD SPECIFICATIONS 2009

314

9.3.5 Rate The rate shall include the cost of material and labour involved in all the operations described above except the hold fasts or metallic fasteners which will be paid for separately. 9.4 FALSE CEILING AND PARTITION FRAMES This work shall be done as specified in 9.3 except that the scantlings need not be planed unless otherwise specified. 9.5 TRUSSES 9.5.0 The work shall be carried out as per detailed drawings and as directed by the Engineer-in-Charge specified timber shall be used. Sawing shall be truly straight and square, and in the direction of the grains. The scantlings shall be accurately planed smooth to the full dimensions and rebate roundings and mouldings shown in the drawings, before the same are framed. Patching or plugging of any kind shall not be permitted. A tolerance of +3 mm and -2 mm shall be allowed in the finished cross sectional dimension. 9.5.1 Joints Joints shall be simple, neat and strong. All mortise and tenon joints, mitred joints, scarfs etc. shall fit in fully and accurately without wedging or fillings. The joints shall be as per detailed drawings. Holes of correct sizes shall be drilled before inserting screws/bolts. Driving in screws with hammer is prohibited. Holes for bolts shall be of uniform diameter. The screws, bolts and nails shall be dipped in oil before using. The heads of nails and screws shall be sunk and puttied or dealt with as instructed by Engineerin-Charge. The gauge and length of nails, screws and bolts shall be approved by the Engineer-inCharge before using on works. 9.5.2 Shaping Form and Cutting The wood sections, as specified or required, shall be straightened, cut square and to correct lengths. A fine accuracy shall be ensured in the fabrication of various member so that these can be assembled without being unduly packed, strained or forced into position and when built up, shall be true to shape and free from twist, kinks, buckles or open joints. 9.5.3 Fabrication As per drawing, a full size truss diagram shall first be drawn on a levelled platform. From this full size diagram, templates of all joints as for tenons, mortises, scarves etc. shall be made for use in the fabrication. The template shall be made to correspond to each member and plate holes for screws and bolts shall be marked accurately on them and drilled. The templates shall be laid on wooden members and the holes for screwing and bolting marked on them. The ends of the wooden members shall also be marked for cutting. The base of columns and the position of anchor bolts shall be carefully set out. Before fabrication of the truss individual members shall be assembled together to ensure close abutting or lapping of the surfaces of the different members and fitted close together as per drawing. 9.5.4 Hoisting and Placing in Position The trusses shall be hoisted and placed in position carefully, without any damage to itself and other building work and injury to workman. The trusses shall be secured to walls by means of holding down bolts or as directed by the Engineer-in-Charge. The necessary mechanical appliances such as lifting tackel, winch etc. for hoisting the truss shall be used. The trusses shall be stayed temporarily till they are permanently secured in position and connected with each other by means of purlins. Holding down bolts cleats used for purlins and bottom plates used for tie and rafter member shall be paid for separately. 9.5.5 Surface Treatment Wood work shall not be painted, oiled or otherwise treated before it has been approved by the Engineer-in-Charge. All portions of timber built into or against or close to masonry or concrete or burried in ground shall be given two coats of boiling coal tar. All junctions of rafters, purlins, beams and wall plates shall be painted with approved wood primer. 315

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9.5.6 Measurements Wood work shall be measured for finished dimensions. No allowance shall be made for dimensions supplied beyond those specified. Length of each piece shall be measured over all nearest to a cm, so as to include projections for tenons, scarves or mitres. Width and thickness shall be measured to the nearest mm. Cubical contents can be worked out in units cubic meters upto 3 places of decimal in whole numbers. 9.5.7 Rate The rate includes the cost of materials and labour involved in all the operations described above. Unless otherwise specified, iron fixtures such as bolts and nuts, M.S. steel plates, holding down bolts and staining, priming, painting or polishing of the work shall be paid for separately. 9.6 PANELLED GLAZED OR PANELLED AND GLAZED SHUTTERS (FIG. 9.2) 9.6.0 Panelled or glazed shutters for doors, windows, ventilators and cupboards shall be constructed in the form of timber frame work of stiles and rails with panel inserts of timber, plywood, block board, veneered particle board, fibre board wire gauze or float glass. The shutters may be single or multipanelled, as shown in the drawings or as directed by the Engineer-in-Charge. Timber for frame work, material for panel inserts and thickness of shutters shall be as specified. All members of the shutters shall be straight without any warp or bow and shall have smooth well planed face at right angles to each other. Any warp or bow shall not exceed 1.5 mm for door shutter and 1 mm for window and ventilator shutters The right angle for the shutter shall be checked by measuring the diagonals and the difference between the two diagonals should not be more than 3 mm. Generally panelled glazed or panelled and glazed shutter shall conform to IS 1003 (Pt. 1 & 2). 9.6.1 Frame Work 9.6.1.1 Timber for stiles and rails shall be of the same species and shall be sawn in the directions of grains. Sawing shall be truly straight and square. The timber shall be planed smooth and accurate to the required dimensions. The stiles and rails shall be joined to each other by plain or haunched mortise and tenon joints and the rails shall be inserted 25 mm short of the width of the stiles. The bottom rails shall have double tenon joints and for other rails single tenon joints shall be provided. The lock rails of door shutter shall have its centre line at a height of 800 mm from the bottom of the shutters unless otherwise specified. The thickness of each tenon shall be approximately one-third the finished thickness of the members and the width of each tenon shall not exceed three times its thickness. 9.6.1.2 Gluing of Joints : The contact surfaces of tenon and mortise shall be treated, before putting together, with bulk type synthetic resin adhesive conforming to IS 851 suitable for construction in wood or synthetic resin adhesive (Phenolic and aminoplastic) conforming to IS 848 or polyvinyl acetate dispersion based adheshive conforming to IS 4835 and pinned with 10 mm dia hardwood dowels or bamboopins or star shaped metal pins; after the frames are put together and pressed in position by means of press. 9.6.1.3 Stiles and bottom rail shall be made out of one piece of timber only. Intermediate rail exceeding 200 mm in width may be of one or more pieces of timber. The width of each piece shall be not less than 75 mm. Where more than one piece of timber is used for rails, they shall be joined with a continuous tongued and grooved joint glued together and reinforced with metal dowels at regular intervals not exceeding 200 mm. 9.6.1.4 Door Shutters 9.6.1.4.1 Finished dimensions and tolerances of components of door shutters has been given in Table 9.5 below. CPWD SPECIFICATIONS 2009

316

TABLE 9.5 Dimensions and Tolerances of Components of Door Shutters Sl. Description No. (a) (b) (c) (d) (e)

Width mm

Vertical Stile, top and freeze rail Lock rail Bottom rail Muntin Glazing bar

Thickness mm A DOOR SHUTTERS 35 + 1 or 40 + 1 35 + 1 or 40 + 1 35 + 1 or 40 + 1 35 +1 or 40 + 1 35 + 1 or 40 + 1

100 + 3 50 + 3 200 + 3 100 + 3 40 + 3

9.6.1.4.2 Size and Types : Size and types of the timber panels and glazed shutters shall generally conform to modular sizes specified in Table 9.6 below. TABLE 9.6 Dimension of Door Shutters Sl. No.

Designation of Doors

(1) (i) (ii) (iii) (iv) (v) (vi) (vii) (viii)

(2) 8DS 20 8DS 21 9DS 20 9DS 21 10 DS 20 10 DS 21 12 DT 20 12 DT 21

Width mm (3) 700 700 800 800 900 900 11001) 11001)

Height mm (4) 1905 (1945 ) 2005 (2045) 1905 (1945) 2005 (2045) 1905 (1945) 2005 (2045) 1905 (1945) 2005 (2045)

Notes : (1) The designation refers to modular sizes of door openings. First number stands for width and the last for height in modules (M = 100 mm). Alphabet D refers to doors, ‘S’ to single and ‘T’ to double leaf shutter. (2) Standard sizes of door frames are covered in IS 4021 and IS 4351. (3) The standard widths and heights for panel doors are arrived at as shown in Fig. 6 of IS 1003 (Pt. 1). In case the modular height is taken from the finished floor level, the height of the door shall be the one given in bracket. In the case of double leave shutters, the rebate in the shutter shall be as given in 6.15 of IS 1003 (Pt. 1). 9.6.1.5 Window and Ventilator Shutters : Window and ventilator shutters shall conform to IS 1003 (Part 2). 9.6.1.5.1 Dimensional Sizes and Tolerances : The finished dimensions and tolerances of different component shall be as given in Table 9.7.

317

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TABLE 9.7 Dimensions and Tolerances of Components of Window and Ventilator Shutters Description of components

Window Shutters

Ventilator Shutters

Width mm 80 ± 3

Thickness mm 25 ± 1 30 ± 1

Width mm 80 ± 3

Munting

60 ± 3

60 ± 3

Glazing bars

40 ± 1

25 ± 1 30 ± 1 25 ± 1 30 ± 1

Stiles and rails

Thickness mm 20 ± 1 22.5 ± 1 25 ± 1 27.5 ± 1 30 ± 1 -do-

40 ± 1

-do-

9.6.1.5.2 Designation : Window and ventilator shutters shall be designated by symbols denoting the width, type and height of window and ventilators in following manner. (a) Width : It shall be indicated by the number of modules in the width of opening (b) It shall be indicated by the following letters of alphabet: W-window, V- Ventilator , S-Single shutter, T-Double shutter (c) Height : It shall be indicted by the number of modules in the height of opening. Example : 10 WT 12 would mean a window shutter suitable for a double shutter window of 10 modules width and 12 modules height. 12 V 6 would mean ventilator shutter suitable for a ventilator of 12 modules width and 6 modules height. 9.6.1.5.3 Sizes : Sizes of window and ventilator shutters shall generally conform to the modular sizes specified in Tables 9.8 and 9.9 respectively. These sizes are derived after allowing the thickness of the frame and a margin of 5 mm all round based on 100 mm module. 9.6.1.5.4 Tolerances on the overall dimensions of window and ventilator shutter shall be + 3 mm. TABLE 9.8 Dimensions of Timber Window Shutters Designation (1) 6 WS 12 10WT 12 12 WT 12 6 WS 13 10 WT 13 12 WT 13

CPWD SPECIFICATIONS 2009

Width mm (2) 500 460 560 500 460 560

318

Height mm (3) 1100 1100 1100 1200 1200 1200

TABLE 9.9 Dimensions of Timber Ventilator Shutters Designation (1) 6V6 10 V 6 12 V 6

Width mm (2) 500 900 1100

Height mm (3) 500 500 500

9.6.2 Mounting and glazing bars where required shall be stubtenoned to the maximum depth which the size of the member would permit or to a depth of 25 mm whichever is less. Unless otherwise specified the finished dimensions of the components of frame work of shutters shall be as given in Table 9.7. The tolerance on width of styles and rail shall be ± 3 mm. The tolerance in thickness will be ± 1 mm. The thickness of all components of frame work shall be the same as the thickness of the shutter. Tolerance on over all dimensions of the shutter shall be ± 3 mm. 9.6.3 Rebating The shutters shall be single-leaf or double leaved as shown in the drawings or as directed by the Engineer-in-Charge. In case of double leaved shutters, the meeting of the stiles shall be rebated by onethird the thickness of the shutter. The rebating shall be either splayed or square type as shown in Fig. 9.2. 9.6.4 Panelling The panel inserts shall be either framed into the grooves or housed in the rebate of stiles and rails. Timber, plywood, and particle board panels as given in para 9.2 of this sub head and shall be fixed only with grooves. The depth of the groove shall be 12 mm and its width shall accommodate the panel inserts such that the faces are closely fitted to the sides of the groove. Panel inserts shall be framed into the grooves of stiles and rails to the full depth of the groove leaving space of 1.5 mm. Width and depth of the rebate shall be equal to half the thickness of stiles and rails. Glass panels, asbestos panels wire gauze panels and panel inserts of cupboard shutters shall be housed in the rebates of stiles and rails. 9.6.4.1 Timber Panels : Timber panels shall be preferably made of timber of large width; the minimum width and thickness of the panel shall be 100 mm, and 15 mm respectively. When made from more than one piece, the pieces shall be jointed with a continuous tongued and grooved joint glued together and reinforced with headless nails at regular intervals not exceeding 100 mm. Depth and thickness of such joint shall be equal to one-third of thickness of panel. The panels shall be designed such that no single panel exceeds 0.5 square metre in area. The grains of timber panels shall run along the longer dimensions of the panels. All panels shall be of the same species of timber unless otherwise specified. 9.6.4.2 Plywood Panels : Plywood boards used for panelling of shutters shall be BWP type or grade as specified in 9.2.2. Each panels shall be a single piece of thickness, 9 mm for two or more panel construction and 12 mm thickness for single panel construction unless otherwise specified. 9.6.4.3 Veneered Particle Board Panels : Veneered Particle board used for panelling of shutters shall be Exterior Grade bonded with BWP type synthetic resin adhesive as specified in 9.2.4.2. Each panel shall be a single piece of thickness 12 mm unless otherwise specified. 9.6.4.4 Fibre Board Panels : Fibre board used for panelling of shutters shall be Exterior Grade bonded with BWP type synthetic resin adhesive Each fibre board panel shall be a single piece unless otherwise specified. 319

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

9.6.4.5 Wire Gauze Panels: Wire Gauze used for panelling of shutters shall be woven with 0.63 mm dia galvanised mild steel wire to form average aperture size of 1.40 mm as specified in 9.2.7. Wire gauze shall be securely housed into the rebates of stiles and rails by giving right angles bend turned back and fixed by means of suitable staples at intervals of 75 mm and over this wooden beading shall be fixed. The space between the rebate and the beading shall be fixed with putty to give a neat finish. Each wire gauze panel shall be a single piece, and the panels shall be so designed that no single panels exceeds 0.5 sqm in area. However, care shall be taken to prevent sagging of wire gauge, of panel by providing and fixing 20 x 20 mm square or equivalent beading to the external face to the required patterns as decided by the Engineer-in-Charge. 9.6.4.6 Glass Panels : Glass panelling (Glazing) shall be done as specified in 9.2.6. Glazing in the shutters of doors, windows and ventilators of bath, WC and Lavatories shall be provided with frosted glass the weight of which shall be not less than 10 kg/sqm. Frosted glass panes shall be fixed with frosted face on the inside. Glass panels shall be fixed by providing a thin layer of putty conforming to IS 419 applied between glass pane and all along the length of the rebate and also between glass panes and wooden beading. 9.6.4.7 Putty can be prepared by mixing one part of white lead with three parts of finely powdered chalk and then adding boiled linseed oil to the mixture to form a stiff paste and adding varnish to the paste at the rate of 1 litre of varnish to 18 kg of paste. Fixing of glass panes without beading shall not be permitted. Glazing shall be done after the shutters have been primed and prepared for painting, so that wood may not draw oil out of putty. 9.6.4.8 Finish : Panels of shutters shall be flat and well sanded to a smooth and level surface. 9.6.5 Beading Beadings in panelled shutter shall be provided where specified in architectural drawings or directed by the Engineer-in-Charge. Each length of beading shall be single piece. Joints at the corners shall be mitred and exposed edges shall be rounded. Beading shall be fixed with headless nails at 75 mm intervals. For external shutters, the beading shall be fixed on the outside face. 9.6.6 Machine/Factory made Shutters Machine made shutters, where specified, shall be procured from an approved factory. For machine made shutters, operations like sawing, planning, making tongue and tenons, cutting grooves, mortises and rebates, drilling holes and pressing of joints shall be done by suitable machines. Machines made shutters shall be brought to the site fully assembled but without any priming coat. Panel inserts of sheet glass and wire gauze may, however, be fixed at site. 9.6.7 Fixing of Shutters For side hung shutters of height upto 1.2 m, each leaf shall be hung on two hinges at quarter points and for shutter of height more than 1.2 m, each leaf shall be hung on three hinges one at the centre and the other two at 200 mm from the top and bottom of the shutters. Top hung and bottom hung shutters shall be hung on two hinges fixed at quarter points of top rail or bottom rail. Centre hung shutter shall be suspended on a suitable pivot in the centre of the frame. Size and type of hinges and pivots shall be as specified. Flap of hinges shall be neatly counter sunk into the recesses cut to the exact dimensions of flap. Screws for fixing the hinges shall be screwed in with screw driver and not hammered in. Unless otherwise specified, shutters of height more than 1.2 mm shall be hung on butt hinges of size 100 mm and for all other shutters of lesser height butt hinges of size 75 mm shall be used. For shutter of more than 40 mm thickness butt hinges of size 125 × 90 × 4 mm shall be used. Continuous (piano) hinges shall be used for fixing cup-board shutters where specified. 9.6.8 Fittings Fittings shall be provided as per schedule of fittings decided by Engineer-in-Charge. Appendix H gives for guidance the schedule of fittings and screws usually provided. Cost of providing and fixing shutter shall include cost of hinges and necessary screws for fixing the same. All other fittings shall be paid for separately. The fittings shall conform to specifications laid down in 9.15. Where the fittings are stipulated to be supplied by the department free of cost, screws for fixing these fittings shall be provided by contractor and nothing extra shall be paid for the same. CPWD SPECIFICATIONS 2009

320

9.6.9 Wooden Cleats and Blocks Wooden cleats and blocks shall be fixed to doors and windows as directed by Engineer-in-Charge, as per size and shape approved by him. These are included in the cost of providing and fixing the shutters. 9.6.10 Measurements Framework and panelling shall be measured separately. 9.6.10.1 Framework of Shutters : The overall length and width of the framework of the shutters shall be measured nearest to a cm in fixed position (overlaps not to be measured in case of double leaved shutters) and the area calculated in square metres correct to two places of decimal. No deduction shall be made to form panel openings or louvers. No extra payments shall be made for shape, joints and labour involved in all operations described above. 9.6.10.2 For panelling of each type or for glazed panel length and width of opening for panels inserts or glazed panels shall be measured correct to a cm before fixing the beading and the area shall be calculated to the nearest 0.01 sq.m. The portions of the panel inserts or glazed panel inside the grooves or rebates shall not be measured for payment. 9.6.11 Rate Rate includes the cost of materials and labour involved in all the operations described above. The framework and panelling of each type or glazed panels shall be paid separately. The rate for framework includes the cost of butt hinges and necessary screws as specified in 9.6.7. However, extra shall be paid for providing moulded beading where specified. Nothing extra shall be paid for plain beading as stated in 9.6.5 when specified in drawing. 9.7 FLUSH DOOR SHUTTERS (Fig. 9.3) 9.7.0 Flush door shutters shall have a solid core and may be of the decorative or non-decorative (Paintable type as per IS 2202 (Part I). Nominal thickness of shutters may be 25, 30 or 35 mm. Thickness and type of shutters shall be as specified. 9.7.1 Width and height of the shutters shall be as shown in the drawings or as indicated by the Engineerin-Charge. All four edges of the shutters shall be square. The shutter shall be free from twist or warp in its plane. The moisture content in timbers used in the manufacture of flush door shutters shall be not more than 12 per cent when tested according to IS 1708. 9.7.2 Core The core of the flush door shutters shall be a block board having wooden strips held in a frame constructed of stiles and rails. Each stile and rail shall be a single piece without any joint. The width of the stiles and rails including lipping, where provided shall not be less than 45 mm and not more than 75 mm. The width of each wooden strip shall not exceed 30 mm. Stiles, rails and wooden strips forming the core of a shutter shall be of equal and uniform thickness. Wooden strips shall be parallel to the stiles. End joints of the pieces of wooden strips of small lengths shall be staggered. In a shutter, stiles and rails shall be of one species of timber. Wooden strips shall also be of one species only but it may or may not be of the same species as that of the stiles and rails. Any species of timber may be used for core of flush door. However, any non-coniferous (Hard wood) timber shall be used for stiles, rails and lipping. 9.7.3 Face Panel The face panel shall be formed by gluing, by the hot-press process on both faces of the core, either plywood or cross-bands and face veneers. The thickness of the cross bands as such or in the plywood shall be between 1.0 mm and 3.0 mm. The thickness of the face veneers as such or in the plywood shall be between 0.5 mm and 1.5 mm for commercial veneers and between 0.4 mm and 1.0 mm for 321

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decorative veneers, provided that the combined thickness of both is not less than 2.2 mm. The direction of the veneers adjacent to the core shall be at right angles to the direction of the wooden strips. Finished faces shall be sanded to smooth even texture. Commercial face veneers shall conform to marine grade plywood and decorative face veneers shall conform to type I decorative plywood in IS 1328. 9.7.4 Lipping Lipping, where specified, shall be provided internally on all edges of the shutters. Lipping shall be done with battens of first class hardwood or as specified of depth not less than 25 mm. For double leaved shutters, depth of the lipping at meeting of stiles shall be not less than 35 mm. Joints shall not be permitted in the lipping. 9.7.5 Rebating In the case of double leaves shutters the meeting of stiles shall be rebated by 8 mm to 10 mm. The rebating shall be either splayed or square type as shown in drawing where lipping is provided. The depth of lipping at the meeting of stiles shall not be less than 30 mm. 9.7.6 Opening for Glazing When required by the purchaser opening for glazing shall be provided and unless otherwise specified the opening for glazing shall be 250 mm in height and 150 mm or 200 mm in width unless directed otherwise. The bottom of the opening shall be at a height of 1.4 m from the bottom of the shutter. Opening for glazing shall be lipped internally with wooden batten of width not less than 25 mm. Opening for glazing shall be provided where specified or shown in the drawing. 9.7.7 Venetian Opening Where specified the height of the venetian opening shall be 350 mm from the bottom of the shutter. The width of the opening shall be as directed but shall provide for a clear space of 75 mm between the edge of the door and venetian opening but in no case the opening shall extend beyond the stiles of the shutter. The top edge of the opening shall be lipped internally with wooden battens of width not less than 25 mm. Venetian opening shall be provided where specified or shown in the drawing. 9.7.8 Tolerance Tolerance on width and height shall be + 3 mm and tolerance on nominal thickness shall be ± 1.2 mm. The thickness of the door shutter shall be uniform throughout with a permissible variation of not more than 0.8 mm when measured at any two points. 9.7.9 Adhesive Adhesive used for bonding various components of flush door shutters namely, core, core frame, lipping, cross-bands, face veneers, plywood etc. and for bonding plywood shall conform to BWP type, phenol formaldehyde synthetic resin adhesive conforming to IS 848. 9.7.10 Tests Samples of flush door shutters shall be subjected to the following tests: (a) End Immersion Test (b) Knife Test (c) Glue Adhesion Test One end of each sample shutter shall be tested for End Immersion Test. Two specimens of 150 x 150 mm size shall be cut from the two corners at the other end of each sample shutter for carrying out Glue Adhesion Test. Knife Test shall be done on the remaining portion of each sample shutter. Test shall be done as laid down in Appendix F of Chapter 9. CPWD SPECIFICATIONS 2009

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9.7.11 Sample Size Shutters of decorative and non-decorative type from each manufacturer, irrespective of their thickness, shall be grouped separately and each group shall constitute a lot. The number of shutters (sample size) to be selected at random from each lot for testing shall be as specified in Table 9.10. If the total number of shutters of each type in a work (and not the lot) is less than twenty five, testing may be done at the discretion of the Engineer-in-Charge and in such cases extra payment shall be made for the sample shutter provided the sample does not fail in any of the test specified in 9.7.10. For knife test, glue adhesive test, slamming test, the end immersion test, the number of shutters shall be as per col. 4 of Table 9.10. TABLE 9.10 Sample Size and Criteria for Conformity Lot Size (1) Upto 26 to 50 51 – 100 101 – 150 151 – 300 301 – 500 501 and above

Sample Size (2) 8 13 20 32 50 80

Permissible defective (3) 0 1 1 1 2 2

no.

of Sub. Sample size (4) 1 2 2 3 4 5

9.7.12 Criteria for Conformity All the sample shutters when tested shall satisfy the requirements of the tests laid down in Appendix F of Chapter 9. The lot shall be declared as conforming to the requirements when numbers of defective sample does not exceed the permissible number given in col. 3 of Table 9.10. If the number of sample shutters found unsatisfactory for a test is one, twice the number of samples initially tested shall be selected and tested for the test. All sample shutters so tested shall satisfy the requirement of the test. If the number of samples found unsatisfactory for a test is two or more, the entire lot shall be considered unsatisfactory. 9.7.13 Fixing This shall be as specified in 9.6.7. 9.7.14 Measurements Length and width of the shutters shall be measured to the nearest cm in closed position covering the rebates of the frames but excluding the gap between the shutter and the frame. Overlap of two shutters shall not be measured. All work shall be measured net as fixed and area calculated in square metres to nearest two places of decimal. No deduction shall be made for providing venetian opening and opening for glazing. 9.7.15 Rates The rate includes the cost of material and labour involved in all the operations described above. Extra rate shall be payable for providing rebates in double leaved shutters. Glazing when provided shall be measured & paid for separately as specified in 9.6.10.2. 9.8 WIRE GAUZE FLY PROOF SHUTTERS 9.8.0 Specified timber shall be used, and it shall be sawn in the direction of the grains. Sawing shall be truly straight and square. The timber shall be planed smooth and accurate to the full dimensions, rebates, roundings and mouldings as shown in the drawings made, before assembly. Patching or plugging of any kind shall not be permitted except as provided.

323

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9.8.1 Stile and Rails The Specifications shall be as described under 9.6.1.3. The stiles and rails shall be given a rebate to receive the wire gauze which shall form the panels. 9.8.2 Wire Gauze This shall be unless specified otherwise conform to para 9.2.7 and 9.6.4.5. The wire gauze shall be bent at right angles in the rebates of stiles and rails, turned back and fixed tight with blue tacks at about 75 mm centres, fixed alternately in the two faces of the rebates. Over this, wooden beading shall be fixed with brads or small screws at about 75 mm centres. The space between the beading and rebates, where the wire gauze is bent, shall be neatly finished with putty, so that the end of the wire gauze may not be visible. 9.8.3 Fixing Fittings, Wooden cleats, blocks and Measurement shall be as specified under 9.6. 9.8.4 Rate This includes the cost of materials and labour involved in all the operations described above, and as specified under 9.6. 9.9 WALL LINING 9.9.0 Specified timber shall be used, and it shall be sawn in the direction of the grains. Sawing shall be truly straight and square. The timber shall be planed smooth and accurate to the full dimensions, rebates, roundings, and mouldings as shown in the drawings made, before assembly. Patchings or plugging of, any kind shall not be permitted except as provided. 9.9.1 Grounds Grounds shall be provided where so specified. These shall consist of first class hard wood plugs or the class of wood used for fabricating the frames, of trapezoidal shape having base of 50 × 50 mm and top 35 × 35 mm with depth of 5.0 cm and embedded in the wall with cement mortar 1:3 (1 cement : 3 fine sand) and batten of first class hard wood or as specified of size 50 × 25 mm or as specified, fixed over the plugs with 50 mm long wood screws. The plugs shall be spaced at 45 to 60 centimetres centre to centre, depending upon the nature of work. The battens shall be painted with priming coat, of approved wood primer before fixing. 9.9.2 Panelling 9.9.2.1 Material : This panelling shall be decorative or non-decorative (Paintable) type as per design and thickness specified by the Engineer-in-Charge, of 2nd class teak wood, FPT-1 or graded wood prelaminated particle board or as specified in item. 9.9.2.2 Ornamental Work : The ornamental wood work shall be painted on the back with priming coat of approved wood primer before fixing the same to the grounds with screws, which shall be sunk into the wood work and their tops covered with putty. The ornamental work shall be made true and accurate to the dimensions shown in the working drawings. The fixing shall be done true to lines and levels. The planks for wall lining shall be tongued and grooved, unless otherwise specified. 9.9.2.3 Measurements : Length and breadth shall be measured correct to a cm. Wall panelling such as teakwood panelling and block panelling, plain lining, and plain skirting each shall be measured separately in square metre nearest to two places of decimal. The moulded work shall be measured in cm running metre i.e. in running metres stating the girth in cm. The sectional periphery (girth) of moulding excluding the portion in contact with wall shall be measured in cm correct to 5 mm and length in metre correct to a cm.

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The measurements for ground shall be taken on the basis of cubical contents of battens and paid for separately, unless otherwise specified. Where only plugs are required to be fixed for the ornamental work, the cost for the same shall be deemed to be included in the rate of ornamental work and no separate payment shall be made for plugs. 9.9.2.4 Rate : The rate includes the cost of materials and labour required for all the operation described above. 9.10 SHELVES 9.10.0 Shelves and vertical partitions of cupboards shall be of timber planks fibre board, particle board, block board or veneered particle board as specified. Thickness and type of planks or boards shall be as specified. Each shelf shall be a single piece and vertical partitions between two consecutive shelves shall be without any joint. Exposed edges of boards having particle board core shall be sealed with 3 mm thick single piece teak wood strips of width equal to the thickness of board with headless pins. The arrangement of shelves and vertical partitions shall be as per drawings or as directed by the Engineerin-Charge. 9.10.1 Fixing Planks for shelves shall be planed on all faces and edges. In case of boards they shall be sawn to the required size truly straight and square. Timber battens 25 x 40 mm unless otherwise specified shall be planed smooth and fixed inside the cupboard with wooden plugs and screws. Shelves shall be fixed to the battens and vertical portions shall be held in position by fixing them to the battens and shelves using screws. Teakwood strips for edge sealing of the boards shall be planed smooth and fixed with headless nails. Tolerance in width shall be ± 1.5 mm and in thickness 1 mm. 9.10.2 Measurements Length and width of shelves and vertical partitions shall be measured correct to a cm. separately for each type of board stating its thickness. Area shall be calculated correct to 0.01 sqm. 9.10.3 Rate It includes the cost of materials and labour required for all the operations described above. 9.11 TRELLIS (JAFFRI) WORK 9.11.0 Specified timber /bamboo shall be sawn/cut in the direction of the grains. Sawing / cutting shall be truly straight and square. The timber / bamboo shall be planed smooth and accurate to the full dimensions, rebates, roundings, and mouldings as shown in the drawings made, before assembly. Patching or plugging of any kind shall not be permitted except as provided. 9.11.1 Plain Trellis (Jaffri) This shall consist of wooden strips or laths 35 x 10 mm section unless otherwise specified planed and nailed together at every alternate crossing. The strips shall cross each other at right angle and shall be spaced 35 mm apart, so as to form 35 × 35 mm square opening or as shown in the drawing. These shall be fixed with nails to the frame. To cover the ends of strips, 50 × 12 mm beading shall be fixed to the frame with screws. The finished work with a tolerance of ± 1 mm may be accepted. 9.11.2 Measurements Width and height of plain trellis work and trellis shutters shall be measured overall correct to a cm. The area shall be calculated in square metres nearest to two places of decimal. 9.11.3 Rate It includes the cost of materials and labour required in all the operations described above. 325

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

9.12 PELMETS 9.12.0 Planks and curtain rods of specified timber shall be used, and it shall be sawn in the direction of the grains. Sawing shall be truly straight and square. The timber shall be planed smooth and accurate to the full dimensions, rebates, roundings, and mouldings as shown in the drawings made, before assembly. Patching or plugging of any kind shall not be permitted. 9.12.1 Sides, front and top of the pelmets shall be of 12 mm planks or boards of specified quality and width unless otherwise stated. These shall project from the wall face by 15 cm or as specified, and shall be securely fixed to walls with wood screws by means of wooden plugs and 10 cm long 25 × 3 mm M.S. flat bent in the form of angle or by any other device approved by the Engineer-in-Charge. The pelmets shall be provided with curtain rods and brackets or curtain rails with rollers, stop ends and brackets wooden, brass or chromium plated brass as specified. Intermediate wooden brackets shall be provided, if the front length of pelmet exceeds 1.5 metres. 9.12.2 Measurements The pelmets box shall be measured along the sides and front planking correct to a centimetre. 9.12.3 Rate The rate includes the cost of sides, front and top planking curtain rods with brackets or curtain rails with rollers labour and materials required for all the operations described above. 9.13 HOLD FASTS 9.13.0 These shall be made from mild steel flat 40 × 5 mm size conforming to IS 7196 without any burns or dents. 5 cm length of M.S. flat at one end shall be bent at right angle and one hole 11 mm dia shall be made in it for fixing to wooden frame with 10 mm dia nut bolt. The bolt head shall be sunk into the wooden frame, 10 mm deep and pluged with wooden plug. At the other end 10 cm length of the hold fast flat shall be forked and bent of length as specified at right angle in opposite direction and embedded in cement concrete block of size 30 x 10 x 15 cm of mix 1:3:6 (1 cement : 3 coarse sand : 6 graded stone aggregate, 20 mm nominal size) or as specified (see Fig. 9.4). 9.13.1 Measurements Measurements for the hold fasts shall be in number. 9.13.2 Rate It includes the cost of labour and material involved in all the operations described above including fixing bolt and cement concrete blocks. 9.14 EXPANDED METAL, HARD DRAWN STEEL WIRE FABRIC AND WIRE GAUZE IN WOODEN FRAMES 9.14.0 Expanded metal, hard drawn steel wire fabric or wire gauge or weld mesh as described in the item of work shall be fixed to the window frames on the outside or inside as per detailed drawings or as directed by the Engineer-in-Charge. These shall be free from rust and other defects. Expanded Metal This shall be in the form of rhombus with its opening diagonals 20 × 60 mm and strands 3.25 mm wide and 1.6 mm thick weighing 3.633 kg/m2 unless otherwise specified. Welded Steel Drawn Wire Fabric This shall conform to IS 4948 and shall have rectangular mesh of 75 × 25 mm size with wires of diameter not less than 5 mm longitudinally and 3.15 mm transversely. Its weight shall be not less than 7.75 kg/m2 unless otherwise specified.

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Wire-Gauze This shall be as per clause 9.2.7. 9.14.1 Fixing Expanded metal, hard drawn steel wire fabric and wire gauze shall be cut in one piece to the size of the frame (out to out). Expanded metal and hard drawn steel wire fabric shall be fixed on to the frame with staples, over which wooden beading 60 x 20 mm shall be fixed with wood screws. 9.14.2 Measurements The length and breadth shall be measured correct to a cm, the area from outside to outside of beading shall be calculated in square metre nearest to two places of decimal. 9.14.3 Rate It includes the cost of labour and materials required for all the operations described above. 9.15 FITTINGS 9.15.0 Fitting shall be of mild steel brass, aluminium or as specified. Some mild steel fittings may have components of cast iron. These shall be well made, reasonably smooth, and free from sharp edges and corners, flaws and other defects. Screw holes shall be counter sunk to suit the head of specified wood screws. These shall be of the following types according to the material used. (a) Mild Steel Fittings : These shall be bright finish black stone enamelled or copper oxidised (black finish), nickel chromium plated or as specified. (b) Brass Fittings : These shall be finished bright satin finish or nickel chromium plated or copper oxidised or as specified. (c) Aluminium Fittings : These shall be anodised to natural matt finish or dyed anodic coating not less than grade AC 10 of IS 1868. The fittings generally used for different type of doors and windows are indicated in Appendix H attached. The fittings to be actually provided in a particular work shall, however, be decided by the Engineer-in-Charge. Screws used for fittings shall be of the same metal, and finish as the fittings. However, chromium plated brass screws or stainless steel screws shall be used for fixing aluminium fittings. These shall be of the size as indicated in respective figures. Fittings shall be fixed in proper position as shown in the drawings or as directed by the Engineer-inCharge. These shall be truly vertical or horizontal as the case may be. Screws shall be driven home with screw driver and not hammered in. Recesses shall be cut to the exact size and depth for the counter sunking of hinges. 9.15.1 Butt Hinges (Fig. 9.5A) These shall be of the following types according to the material used. (a) Mild steel butt hinges (Medium). (b) Cast brass butt hinges light/ordinary or heavy. (c) Extruded aluminium alloy butt hinges. 9.15.1.1 Mild Steel (Medium) (Fig. 9.5A) : These shall be medium type manufactured from M.S. sheet. These shall be well made and shall be free from flaws and defects of all kinds. All hinges shall be cut clean and square and all sharp edges and corners shall be removed. These shall generally conform to IS 1341. 327

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

Hinge Pin : Hinge pin shall be made of mild steel wire. It shall fit inside the knuckles firmly and rivetted head shall be well formed so as not to allow any play or shake, and shall allow easy movement of the hinge, but shall not cause looseness. Knuckles : The number of knuckles in the hinges of different sizes shall be as per IS 1341. The size of knuckles shall be straight and at right angle to the flap. The movement of the hinges shall be free and easy and working shall not have any play or shake. Screw Holes : The screw holes shall be clean and counter sunk. These shall be suitable for counter sunk head wood screws and of the specified size for different types, and sizes of hinges. The size of the holes shall be such that when it is counter sunk it shall be able to accommodate the full depth of counter sunk head of the wood screws. The nos. of screw holes shall as specified in IS 1341. 9.15.1.1.1 Sampling and Criteria for Conformity : The number of butt hinges to be selected from a lot shall be depend on size of lot and shall be in accordance with Table 9.11 below. Butt hinges for testing shall be selected at random from at least 10 per cent of the randomly selected packages subjected to minimum of three equal number of hinges being selected from each package. All butt hinges selected shall be checked for dimensions and tolerance requirements. Defects in manufacture and finish shall also be checked and lot shall be considered conforming to the requirement of this specifications, if the number of defective hinges among those tested does not exceed the corresponding number given in Table 9.11. TABLE 9.11 Scale of Sampling and Criteria for Conformity Sl. No. 1 1. 2. 3. 4. 5.

Lot size 2 Upto 150 151 to 300 301 to 500 501 to 1000 1001 and above

Sample Size

Permissible No. of Defective hinges

3 5 20 32 50 80

4 0 1 2 3 5

9.15.1.2 Cast Brass : These shall be light/ordinary or heavy as specified. These shall be well made and shall be free from flaws and defects of all kinds. These shall be finished bright or chromium plated or oxidised or as specified. These shall generally conform to IS 205. Hinge Pin : Hinge pin shall be made of brass or of stainless steel. The hinge pins shall be firmly rivetted and shall be properly finished. The movement of the hinge pin shall be free, easy and square and shall not have any play or shake. Knuckles : The number of knuckles in each hinge shall not be less than five. The number of knuckles in case of sizes less than 40 mm shall be three. The sides of the knuckles shall be straight and at right angle to the flap. The movement of the hinge pin shall be free and easy and working shall not have any play or shake. Screw Holes : The screw holes shall be clean and counter sunk and of the specified size for different types and size of hinges. The size of the holes shall be such that when it is counter sunk it shall be able to accommodate the full depth of counter sunk head of wood screw specified. 9.15.1.3 Extruded Aluminium Alloy : These shall be manufactured from extruded sections. These shall be well made and free from flaws and defects of all kinds. These shall generally conform to IS 205.

CPWD SPECIFICATIONS 2009

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Hinge Pin : Hinge pin shall be made of mild steel (galvanised or aluminium alloy). The aluminium alloy hinge pin shall be anodised. The hinge pin shall be finally rivetted and shall be properly finished. The movement of hinges shall be free easy and square and shall not have any play or shake. Knuckles : Number of knuckles in each hinge pin shall not be less than 5. The number of knuckles in case of sizes less than 40 mm be straight and at right angle to the flap. The movement of the hinge pin shall be free and easy and working shall not have any play or shake. Screw Holes : The screw holes shall be suitable for counter sunk head wood screws, and of specified sizes for different type of hinges. The size of the holes shall be such that when it is counter sunk it shall be able to accommodate the full depth of counter sunk head of wood screw specified. 9.15.1.4 Sampling and Criteria for Conformity : The number of butt hinges to be selected from a lot shall depend on the size of lot and shall be in accordance with Table 9.12. Butt hinges for testing shall be taken at random from at least 10 per cent of the package subject to a minimum of three, equal number of hinges being selected from each package. All butt hinges selected from the lot shall be checked for dimensional and tolerance requirements. Defects in manufacture and finish shall also be checked. A lot shall be considered conforming to the requirements of this specification if the number of defective hinges among those tested does not exceed the corresponding number given in Table 9.12. TABLE 9.12 Scale of Sampling and Criteria for Conformity Sl. No.

Lot size

1 2 3 4 5

Upto 200 201 to 300 301 to 500 501 to 800 801 and above

Sample size 15 20 30 40 55

Permissible No. of defective hinges 0 1 2 2 3

Note: Any hinge which fails to satisfy the requirements of any one or more of the characteristics shall be considered as defective hinge. 9.15.2 Parliament Hinges (Fig. 9.5B) 9.15.2.1 These shall be of mild steel cast brass or as specified, and shall generally conform to IS 362. The size of parliament hinges shall be taken as the width between open flanges. Mild steel parliament hinges shall be copper oxidised (thick finish) or as specified. The brass parliament hinges shall be finished bright, chromium plated or oxidised or as specified. 9.15.2.2 The hinge pin shall be made of mild steel in the case of brass hinges. The hinge pin shall be mild steel (galvanised) in the case of aluminium alloy hinges. The hinge pin shall be firmly rivetted and shall be properly finished. The movement of the hinges shall be free, easy and square, and shall not have any play or shake. All screw holes shall be clean and counter sunk to suit the counter sunk head of wood screws specified. 9.15.2.3 Sampling Criteria for and Conformity : The number of parliament hinges to be selected from a lot shall depend on the size of lot and shall be in accordance with Table 9.13. Parliament hinges for testing shall be taken at random. All hinges selected from the lot shall be checked for dimensional and tolerance requirements. Defects in manufacture and finish shall also be checked. A lot shall be considered conforming to the requirements of this specification if the number of defective hinges among those tested does not exceed the corresponding number given in Table 9.13.

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TABLE 9.13 Lot Size

Sample Size

Upto 150 151 to 300 301 to 500 501 to 1000 1001 and above

13 20 32 50 80

Permissible No. of Defective hinges 0 1 2 3 5

Note: Any hinge which fails to satisfy the requirements of any one or more of the characteristics shall be considered as defective hinge. 9.15.3 Spring Hinges (Single or double acting) 9.15.3.1 These shall be single acting when the shutter is to open on one side only or double acting when the shutter opens on both sides. These shall be made of M.S. or brass as specified, and shall generally conform to IS 453. Hinges shall work smoothly and shall hold the door shutter truly vertical in closed position. Each double-acting spring hinge shall withstand the following tests which shall be carried out after fixing it to a swing door in the normal manner. (a) When the door is pushed through 90° and released 2000 times on each side in quick succession the hinge shall show no sign of damage or any appreciable deterioration of the components during or on completion of the test. (b) The door shall require a force of 2.0 ± 0.5 kg for 100 mm hinges and 3.0 ± 0.5 kg for 125 mm and 150 mm hinges at a distance of 45 cm from the hinge pin to move the door through 90º. The size of spring hinge shall be taken as the length of the plate. 9.15.3.2 These shall be of the following type: (a) Mild Steel : The cylindrical casing shall be made either from M.S. sheet of 1.60 mm thickness, lap jointed and brazed, welded and rivetted, or from solid drawn tube of thickness not less than 1.60 mm; or from mild sheet of 1.60 mm thickness pressed to from the two casing and the distance piece. It shall be stove enamelled black or copper oxidized or as specified. (b) Cast Brass : The cylindrical casing shall be made either from brass sheet of 1.60 mm thickness, lap jointed and brazed, or from solid drawn brass tube of not less than 1.60 mm thickness. It shall be satin, bright nickle plated or copper oxidized or as specified. 9.15.3.3 Sampling : The number of spring hinges shall be selected from the lot and this number shall depend on the size of the lot and shall be in accordance with Table 9.14. TABLE 9.14 Lot size

Sample size

Permissible No. of defective spring hinges

13 20 32 50 80

0 1 2 3 5

Upto 100 101 to 300 301 to 500 501 to 1000 1001 and above CPWD SPECIFICATIONS 2009

330

9.15.4 Rising Hinges These shall be made of brass, finished bright or chromium plated or oxidised or as specified. Its shape and pattern shall be approved by the Engineer-in-Charge. The size of the rising hinge shall be taken as the length of its plate. 9.15.5 Continuous Piano Hinges (Fig. 9.6B) 9.15.5.1 These shall be made from mild steel or aluminium alloy sheet, these shall generally conform to IS 3818. All screw holes shall be clean and counter sunk. Piano hinges shall be fixed in the entire length of the cup board shutters. Its size will be the width of the two flaps when open. 9.15.5.2 M.S. Piano Hinges : These shall be made from 1 mm or 0.80 mm thick M.S. sheets and shall be protected with anti-corrosive treatment, such as bright polished, chromium plated or oxidised finish. Hinge pin shall be of galvanised mild steel. It shall fit in the knuckle firmly so as not to allow any play or shake and shall allow easy movement of hinge, but shall not cause looseness. The sides of the knuckles shall be straight and at right angles to the flap. The movement of the hinge shall be free and easy and working shall not have any play and shake. 9.15.5.3 Aluminium Piano Hinges : These shall be made of aluminium alloy sheet and shall be anodised. The anodic coating shall not be less than the grade AC 15 of IS 1868. Hinge pin shall be made of aluminium alloy with anodic coating not less than the grade of AC-15 of IS 1868. The hinge pin shall fit in the knuckle firmly so as not to allow any play or shake and shall allow easy movement of hinge but shall not cause looseness. The sides of the knuckles shall be straight and at right angles to the flap. The movement of the hinge shall be free and easy, and working shall not have any play and shake. 9.15.5.4 Sampling and Criteria for Conformity : It shall be same as specified in clause 9.15.1.4. 9.15.6 Tee Hinges (Fig. 9.6A) These shall be made from M.S. sheets and shall be either bright finished or stove enamelled black or as specified. These shall generally conform to IS 206 (Tee hinges shall be well made, free from burrs, flaws, and defects of any kind. The movement shall be square, and the working shall be free and easy without any play or shake. The hole for the hinge shall be central to the bore and shall be square. The hinge pin shall be firm and rivetted over, so that the heads are well formed. All screw holes shall be clear and counter sunk and shall be suitable for the counter sunk head of wood screws. 9.15.6.1 Sampling and Criteria for Conformity : It shall be same as specified in clause 9.15.1.4. 9.15.7 Sliding Door Bolts (Aldrops) (Fig. 9.7) 9.15.7.1 These shall be of mild steel, cast brass, aluminium or as specified, and shall be capable of smooth sliding action. 9.15.7.2 M.S. Sliding Door Bolts : These shall be made of M.S. sheets and M.S. rods and shall generally conform to IS 281. M.S. sliding door bolts shall be copper oxidised (black finish) or as specified. 331

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

9.15.7.3 Cast Brass Sliding Door Bolts : These shall be made from rolled brass and shall generally conform to IS 2681. The hasp shall be of cast brass and secured to the bolt as shown in Fig. 9.7. Alternatively, the hasp and the bolt may be cast in one piece. The fixing and staple bolts shall be cast with 6 mm studs. Bolts shall be finished to shape and have threaded ends and provided with robs washers and nuts of square or hexagon type. All components shall be finished smooth and polished before assembly. Cast brass sliding bolts shall be finished bright or chromium plated or oxidised or as specified. 9.15.7.4 Aluminium Sliding Door Bolts : These shall be made of aluminium alloy and shall generally conform to IS 2681. Aluminium sliding door bolts shall be anodized. All screw holes shall be counter sunk to suit the counter sunk head of screws of specified sizes. All edges and corners shall be finished smooth. In case of single leaf door, when iron socket plate or a brass or aluminium fixing bolts (or sliding door bolt) cannot be fixed, hole of suitable size shall be drilled in the door frame and an iron or brass plate cut to shape shall be fixed at the face of the hole. The leading dimensions of the sliding door bolts are illustrated. 9.15.7.5 Sampling and Criteria for Conformity : The number of sliding door bolt to be selected from a lot shall depend on the size of lot and shall be in accordance with Table 9.15. For testing shall be taken at random from at least 10 percent of the package subject to a minimum of three, equal number of door bolts being selected from each package. All door bolts selected from the lot shall be checked for dimensional and tolerance requirements. Defects in manufacture and finish shall also be checked. A lot shall be considered conforming to the requirement of this specification if the number of defects sliding door bolts among those tested does not exceed the corresponding number given in Table 9.15. TABLE 9.15 Lot. size Upto 150 151 to 300 301 to 500 501 to 1000 1001 and above

Sample Size 5 20 32 50 81

Permissible speed Decorative sliding door bolts 0 1 2 3 5

9.15.8 Tower Bolts (Fig. 9.8) 9.15.8.0 These shall generally conform to IS 204 (Part. I) & IS 204 (Part. II). Tower bolts shall be well made and shall be free from defects. The bolts shall be finished to the correct shape and shall have a smooth action. All tower bolts made with sheet of 1.2 mm thickness and above shall have counter sunk screw holes to suit counter sunk head of wood screws. All sharp edges and corners shall be removed and finished smooth. The height of knob of tower bolt when the door, window etc. is in closed position from the floor level shall be not more than 1.9 metre. 9.15.8.1 Tower bolts shall be of the following types: (a) Aluminium barrel tower bolts with barrel and bolt of extruded sections of aluminium alloy. The knob shall be properly screwed to the bolt and rivetted at the back. (b) Brass tower bolts with cast brass barrel and rolled or cast brass bolt. or Brass tower bolts with barrel of extruded sections of brass and rolled or drawn brass bolt. The knobs of brass tower bolts shall be cast and the bolt fixed with knob, steel spring and ball shall be provided between the bolt and the barrel. CPWD SPECIFICATIONS 2009

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(c) Mild steel barrel tower bolts with mild steel barrel and mild steel bolt. or Mild steel tower bolts with mild steel barrel and cast iron bolts. The plates and straps after assembly shall be firmly rivetted or spot welded. The rivet head shall be properly formed and the rivet back shall be flush with the plate. These shall be made in one piece. 9.15.8.2 Unless otherwise specified bolt shall have finish as given below : (a) Mild steel tower bolts (Types 1 and 2) Bolts bright finished or plated as specified and barrel and socket stove enamelled black. (b) Brass tower bolts (type 3 to 5) Bolt and barrel polished or plated as specified. (c) Aluminium alloy tower bolts (type 6) Bolt and barrel anodized. The anodic film may be either transparent or dyed as specified. The quality of anodized finish shall not be less than grade AC-10 of IS 1868. 9.15.8.3 Sampling and Criteria for Conformity : It shall be same as specified in clause 9.15.1.4. 9.15.9 M.S. Locking Bolt with Holes for Pad Locks 9.15.9.1 This shall conform to IS 7534. 9.15.9.2 This shall be of mild steel polished bright or copper oxidised batch electrogalvanised or stove enamelled. In case of stove enamelled locking bolts, the bolt may be finished bright. 9.15.10 Pull Bolt Locks (Fig. 9.9) 9.15.10.1 These shall be of M.S. cast brass or aluminium as specified. M.S. pull bolt locks shall be copper oxidized (black finish) or as specified. 9.15.10.2 Brass pull bolt locks shall be finished bright, chromium plated or oxidised as specified. Aluminium pull bolt locks shall be anodised and the anodic coating shall not be less than grade. A.C. 10 of IS 1868. The bolt shall be 10 mm in diameter and the fixing plate 3 mm thick. The stop block shall be screwed to the fixing plate by a small ball and spring over which the bolt shall slide. 9.15.10.3 The fixing plate shall have four holes for fixing it to the door leaf, two of which shall be square to receive 6 mm dia. bolts with round heads, the remaining two shall receive machine screwed with lock nuts. The receiving plate shall be of the same width and thickness as the fixing plate and shall have 3 counter sunk holes. Where the bolt slides into wooden members, like the chowkhat, which have a rebate, the receiving plate shall also be correspondingly shaped so as to fit into the rebate. The screws and bolts shall have the same finish as the main bolt. The leading dimensions of pull bolt locks are given in the drawing. The denominating size of the pull bolt locks shall be length of the fixing plate between guides plus the thickness of the guides. 9.15.11 Door Latch 9.15.11.1 This shall be of mild steel, cast brass, or as specified and shall be capable of smooth sliding action. In case, of mild steel latch, it shall be copper oxidized (black finish) or as specified and in case of brass, it shall be finished bright, chromium plated or oxidized or as specified. The size of door latch shall be taken as the length of the latch.

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9.15.12 Indicating Bolt (Vacant/Engaged) These shall be of cast brass finished bright chromium plated, or oxidized or as specified. The shape and pattern shall be approved by the Engineer-in-Charge. 9.15.13 Mortice Lock and Latch (Fig. 9.10) 9.15.13.0 This should generally conform to IS 2209. 9.15.13.1 The size of the mortice lock shall be denoted by the length of the body towards the face and it shall be 65 mm, 75 mm and 100 mm as specified. The measured length shall not vary more than 3 mm from the length specified. 9.15.13.2 Non-interchangeable Keys : Testing of non-interchangeable keys shall be as per IS 2209. 9.15.13.3 The clear depth of the body shall not be more than 15 mm. The fore end shall be firmly fitted to the body suitably by counter sunk head screw. The latch bolt shall be of specified material and of section not less than 12 x 16 mm for all sizes of locks. If made of two piece construction both parts shall be rivetted. Ordinary lever mechanism with not less than two levers shall be provided. False levers shall not be used. Lever shall be fitted with one spring of phosphor bronze or steel wire and shall withstand the tests as provided in IS 2209. 9.15.13.4 Locking bolts, spring and strike plate shall conform to IS 2209. 9.15.13.5 Handles : These shall conform to IS 4992. 9.15.13.6 Keys : Each lock shall be provided with two keys. 9.15.13.7 Sampling, Criteria for Conformity : It shall be the same as specified in clause 9.15.1.4. 9.15.13.8 Tests : The finally assembled locks shall be tested as prescribed in Appendix ‘G’ of Chapter 9. 9.15.14 Mortice Latch (with Locking Bolt) 9.15.14.1 These are generally used in doors of bath rooms, WC’s and private rooms. 9.15.14.2 Mortice latch shall, in respect of shape, design and mechanism of the latch and its components parts, generally conform to IS 5930. The material used for the different component parts of the latch shall comply with Tables 1 and 2 of IS 5930, unless otherwise specified. 9.15.14.3 The size of the latch shall be denoted by the length of the body towards the face and shall be 65 mm, 75 mm or 100 mm as specified. The depth of the body shall not be more than 15 mm. 9.15.14.4 The latch shall be of size 10 × 18 mm of shape as shown in Fig. 1 of IS 5930. The locking bolt shall be of section not less than 8 x 25 mm for all size of locks. The mechanism of the latch bolt, its spring, striking plate etc. shall be as described in IS 5930. 9.15.14.5 The handles provided shall conform to IS 4992. 9.15.14.6 Sampling, criteria for conformity shall be same as per clause 9.15.1.4. 9.15.15 Mortice Lock and Latch (Rebated) 9.15.15.1 These are slightly different from mortice lock described in 9.15.14 and are designed for use in double leaved doors. These should generally conform to IS 6607.

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9.15.15.2 Handles, Keys, Sampling, Criteria for Conformity and Test : These shall be same as specified in clause 9.15.14. 9.15.16 Mortice Night Latch (Fig. 9.11) 9.15.16.1 This is a mortice lock having a single spring bolt withdrawn from the outside by using the key and from inside by turning the knob and with an arrangement whereby the lock can be prevented from being opened by its key from outside while the night latch is used from inside the room. 9.15.16.2 This should generally conform to IS 3847. 9.15.16.3 It shall be cast or sheet brass, cast or sheet aluminium alloy or Mild steel as specified and of best quality of approved make. These shall be bright finished or copper oxidised (black) finish as specified. Nominal size of the latch shall be denoted by the length of the face over the body in millimetres. These shall have not less than two levers. False (Dummy) levers shall not be allowed. 9.15.16.4 Keys : Each latch shall be provided with two keys which should work smoothly and without any appreciable friction in the lock. 9.15.17 Cupboard or Wardrobe Lock This should generally conform to IS 729. The size of the cupboard lock shall be 40, 50, 65 & 75 mm. This shall be made of cast brass and shall be of the best make of approved quality. These shall be finished bright or chromium plated or oxidised or as specified. The size of the lock shall be denoted by the length of the face across the body in mm. These locks shall be fitted with four, five or six levers as specified. False (dummy) levers shall not be used. 9.15.18 Kicking Plates 9.15.18.1 This shall be of brass (finished bright or chromium plated or oxidised) bronze, stainless steel, aluminium or as specified. Aluminium kicking plates shall be anodised and the anodic coating shall not be less than grade AC-10 of IS 1868. It shall be made from a plate of minimum thickness 3.0 mm & 1.5 mm in case of stainless steel. Shape of the plate shall be as specified. This shall have bevelled or straight edges and shall be fixed by means of counter sunk or rounded screws of the same material and finish as that of the plate. The shape and pattern shall be according to the drawings and as approved by the Engineer-in-Charge. 9.15.19 Door Handles (Doors and Windows) (Fig. 9.12) 9.15.19.1 These should generally conform to IS 208. The door handles shall be well made and free from defects. These shall be finished correct to shape and dimensions. All edges and corners shall be removed and finished smooth so as to facilitate easy handling. Cast handle shall be free from casting defects. Where the grip portion of the handle is joined with the base piece by mechanical means, the arrangement shall be such that the assembled handle shall have adequate strength comparable to that of integrally cast type handles. 9.15.19.2 Door handles shall be of the following types according to the material used: (a) Cast or Sheet Aluminium Alloy Handles : These shall be of aluminium of specified size, and of shape and pattern as approved by the Engineer-in-Charge. The size of the handle shall be determined by the inside grip of the handle. Door handles shall be of 100 mm size and window handles of 75 mm size unless, otherwise specified. These shall be fixed with 25 mm long wood screws of designation No. 6. Aluminium handles, shall be anodized and the anodic coating shall not be less than grade AC 15 - IS 1868 as specified. The finish can be bright natural, matt or satin or dyed as specified. 335

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(b) Cast Brass Handles: These shall be of cast brass of specified size and of the shape and pattern as approved by the Engineer-in-Charge. The size of the handle shall be determined by the inside grip of the handle. Door handles shall be of 100 mm size and window handles of 75 mm size, unless otherwise specified. These shall be fixed with 25 mm long wood screws of designation No 6. Brass handles shall be finished bright satin or nickel chromium plated or copper oxidised or as specified. (c) Mild Steel Handles : These shall be of mild steel sheet, pressed into oval section. The size of the handles will be determined by the inside grip of the handle. Door handles shall be 10 mm size and window handles of 75 mm size unless otherwise specified. These shall be fixed with 25 mm long wood screws of designation No. 6., Iron handles shall be copper oxidised (black finish) or stove enamelled black or as specified. 9.15.19.3 Sampling and Criteria for Conformity : The number of handles to be selected from a lot shall depend on the size of lot and shall be in accordance with Table 9.16. Handles for testing shall be selected at random for at least 10 percent of packages. Subject to a minimum 3, equal number of door handles being selected from each such package. All door handles shall be checked for dimensional requirement and finish. Any door handle which fails to satisfy the requirement of dimensions or finish or both shall be considered as defective. A lot shall be considered as conforming to requirement of this specification, if the number of defective handles among those tested does not exceed the corresponding number of defectives is greater than or equal to rejection number given in column 4 of Table 9.16, the lot shall be deemed as not meeting the requirements of this specification. TABLE 9.16 Scale of Sampling and Criteria for Conformity Lot size (1) Upto 50 51 to 90 91 to 150 151 to 280 281 to 500 501 to 1200 1201 and above

Sample size (2) 8 13 20 32 50 80 125

Acceptance no. (3) 0 1 1 2 3 5 7

Rejection no. (4) 1 2 2 3 4 6 8

9.15.20 Floor Door Stopper (Fig. 9.13) 9.15.20.1 The floor door stopper shall conform to IS 1823. This shall be made of cast brass of overall size as specified and shall have rubber cushion. The shape and pattern of stopper shall be approved by the Engineer-in-Charge. It shall be of brass finished bright, chromium plated or oxidised or as specified. The size of floor stopper shall be determined by the length of its plate. It shall be well made and shall have four counter sunk holes for fixing the door stoppers to the floor by means of wood screws. The body for housing of the door stopper shall be cast in one piece and it shall be fixed to the cover plate by means of brass or mild steel screws and cover plate shall be of casting or of sheet metal. The spring shall be fixed firmly to the pin. Tongue which would be pressed while closing or opening of the door shall be connected to the lower part by means of copper pin. On the extreme end a rubber piece shall be attached to absorb shock. All parts of the door stopper shall be of good workmanship and finish, burrs and sharp edges removed. It shall be free from surface and casting defects. Aluminium stopper shall be anodised and anodic film shall not be less than grade AC-10 of IS 1868. 9.15.20.2 Sampling and Criteria for Conformity : The number of floor door stoppers to be selected from each lot shall depend on the size of the lot and shall be in accordance with col. 1 and 2 of Table 9.17. These stoppers shall be selected at random from at least 10 percent of the randomly selected packages subject to a maximum of three equal number of stoppers being selected from each such package. CPWD SPECIFICATIONS 2009

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All the floor stoppers selected shall be checked for dimensional requirement, material, manufacture and finish. Any of door stopper which fails to satisfy any one or more of these requirement shall be considered as defective door stopper. A lot shall be considered as conforming to the requirements of this specifications if the number of defective floor door stoppers among these tested does not exceed the corresponding number given in col. 3 of Table 9.17. Otherwise it shall be considered as not conformity to the requirements of this specification. TABLE 9.17 Scale of Sampling and Criteria for Conformity Lot Size

Sample Size

(1) Upto 100 101 to 300 301 to 500 501 to 1000 1001 and above

Permissible number of defective floor Door stoppers (3) 0 1 2 3 5

(2) 5 0 32 50 80

TABLE 9.18 Requirements for Rubber for Use in Floor Door Stoppers Particulars Requirements Relative density Max. 1.3 Hardness 60 + 5 Ageing for 24 hours at 100o + (a) Change in initial hardness 1oC (b) Shall not develop brittleness + 5, – 0

Testing Procedure IS 3400 (Part IX) IS 3400 (Part 2) IS 3400 (Part II) -do-

9.15.21 Hanging Rubber Door Stopper 9.15.21.1 These shall be of cast brass, finished bright, chromium plated or as specified. Aluminium stopper shall be anodised and the anodic coating shall not be less than grade AC-10 of IS 1868. The size and pattern of the door stopper shall be approved by the Engineer-in-Charge. The size shall be determined by its length. 9.15.22 Universal Hydraulic Door Closer (Exposed Type) 9.15.22.1 These shall be made of cast iron/aluminium alloy/zinc alloy and of shape and pattern as approved by the Engineer-in-Charge. 9.15.22.2 These shall generally conform to IS Specifications for door closers (Hydraulically regulated) IS 3564. 9.15.22.3 The door closers may be polished or painted and finished with lacquer to desired colour. Aluminium alloy door closer shall be anodized and the anodic coating shall not be less than grade AC 15 of IS 1868. All dents, burrs and sharp edges shall be removed from various components and they shall be pickled, scrubbed and rinsed to remove greese, rust, scale or any other foreign elements. After pickling, all the M.S. parts shall be given phosphating treatment in accordance with IS 3618. 9.15.22.4 The nominal size of door closers in relation to the weight and the width of the door size to which it is intended to be fitted shall be given in Table 9.19.

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TABLE 9.19 Type and Designation of Door Closers Designation of closers 1. 2. 3.

Mass of the door (kg) Upto 35 36 to 60 61 to 80

Width of the door (mm) Upto 700 701 to 850 851 to 1000

Remarks

For light doors such as double leaved and toilet doors. Interior doors, such as of bed rooms, kitchen and store Main doors in a building, such as entrance doors

9.15.22.5 Sampling and Criteria for Conformity : All the door closer of the same nominal size and shape and from the same batch of manufacture, in one consignment shall constitute a lot. The number of door closers to be taken at random from a lot shall depend upon the size of the lot. (Table 9.20). The sample shall be tested for construction, finish, dimensions, interchangeability of parts and performance in accordance of Table 9.20. Any door closer failing in any one or more of these characteristics shall be considered as defective. If in the first sample, the number of defective door closer is less than or equal to corresponding acceptance number, the lot shall be declared as conforming to the requirement of these characteristics. If the number of defective door closer is greater than or equal to the rejection number, the acceptance number but less than the rejection number, lot shall be deemed as not meeting with requirements of these characteristics. If the number of defectives is greater than the acceptance number, but less than the rejction number, a second sample of the size equivalent to that of the first shall be taken to determine the conformity or otherwise of the lot. The number of defective door closers found in the first and the second sample shall be combined and if the combined number of defective thus obtained is less than or equal to the corresponding acceptance number, the lot shall be declared as conforming to the requirements of these characteristics. Endurance Test- Two door closer in case of lot size 280 or less and five door closers in case of lot size more than 280 shall be selected from those already found satisfactory. These door closers shall be tested for the endurance test. If all the door closers tested for endurance test satisfy the requirement of this standard, the lot shall be deemed as having satisfied the requirements of endurance test, otherwise not. TABLE 9.20 No. of door Sample closers in the lot Upto 50 First Second 51 to 90 First Second 91 to 150 First Second 151 to 280 First Second 281 to 500 First Second 501 to 1200 First Second 1201 to 3200 First Second 3201 and above First Second

CPWD SPECIFICATIONS 2009

Sample size 8 8 13 13 20 20 32 32 50 50 80 80 125 125 200 200

Commulative sample size 8 16 13 26 20 40 32 64 50 100 80 160 125 250 200 400

338

Acceptance Number 0 1 0 1 0 3 1 4 2 6 3 8 5 12 7 18

Rejection Number 2 2 2 2 3 4 4 5 5 7 7 9 9 13 11 19

9.15.22.6 Performance Requirements : After being fitted in its position when the door is opened through 90°, the same should swing back to angle of 20° ± 5° with nominal speed but thereafter, the speed should get automatically retarded and in case of doors with latches, it should be so regulated that in its final position the door smoothly negotiates with the latch. 9.15.23 Casement Brass Stays (Straight Peg Type) (Fig. 9.14) 9.15.23.1 These shall be made of mild steel, cast brass, aluminium (extruded section) or plastic (Polypropylene) as specified. Mild steel casement stays shall be a copper oxidised (black finish) or as specified. Cast brass stays shall be finished bright or chromium plated or as specified. Aluminium stays shall be anodised and the anodic coating shall not be less than grade AC-10 of IS 1868. Aluminium and M.S. stays shall be made from channel section. The stays shall not weigh less than that indicated below: 200 mm 250 mm 300 mm

0.24 kg each 0.28 kg each 0.33 kg each

9.15.23.2 The shape and pattern of the stays shall be approved by the Engineer-in-Charge. The size of stays shall be determined by its length as shown in the plate. The plastic (Polypropylene) stays shall conform to IS 6318. 9.15.24 Quadrant Stays 300 mm These shall be made of cast brass and finished bright or chromium plated or as specified. The shape and pattern shall be approved by the Engineer-in-Charge. It shall not weigh less than 0.20 kg each. 9.15.25 Hasp and Staple Safety Type (Fig. 9.15) 9.15.25.1 This shall be made of mild steel, cast brass or aluminium as specified. This shall generally conform to IS 363. M.S. Hasp and staples shall be finished black enamelled, or copper oxidised (black finish) or as specified. Brass hasp and staples shall be finished bright chromium plated or oxidised or as specified. Aluminium hasp and staples shall be anodized and the anodic coating shall not be less than grade AC 15 of IS 1868. 9.15.25.2 M.S. hasp and staples shall be manufactured from M.S. sheet and brass hasp and staples by casting and Aluminium hasp and staples shall be made from dye section. The hinge pin which in all cases shall be of mild steel, shall be firm and its rivetted heads well formed. The movement of hasp shall be free, easy and square and shall not have any play or shake. The hasp shall fit, in the staple correctly. The size shall be determined by the length of the bigger of the hasp. 9.15.25.3 The staple except in the case of cast one, shall be rivetted properly to its plate. The ends of the hinge pin for the safety type hasp shall be rivetted and properly finished. All screw holes shall be clean and counter sunk to suit counter sunk wood screw. All edges and corners shall be rounded. 9.15.26 P.T.M.T (Polytetra Methyline Tetraphthalate) Fittings 9.15.26.0 PTMT (Polytetra Methylene Tetraphthalate) is an engineering plastic (raw material imported) and have following physical properties:(i) Tensile Strength : 500 Kg/cm² (ii) Compressive Strength : 900 Kg/ cm² (iii) Rockwell hardness L-scale : 75 (iv) Working temperature : -45º to 120ºC. (v) E Value : 85000 Kg/cm² (vi) Density : 1.3 gm/cc (vii) Impact Strength : No Break 339

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P.T.M.T. fitting shall be in different colours like White, Green, Blue, Derby Brown, Mushroom, Black, Gold, Silver & Broonze or any colours agreed by the manufactures and purchaser. P.T.M.T. fittings are suitable for internal doors shutters kitchen, bath w.c. & cabinet etc. These shall not be used in external door and where security is concern. Screws used for fittings shall be counter sunk cross head of chromium plated brass or stainless steel. Sizes of screws shall be of same size as used in case non ferrous material door/window fittings. 9.15.26.1 P.T.M.T. Butt Hinges : These shall of the material as mentioned in para 9.15.26.0 above. These shall be of required colour/shade ceramic look, glassy smooth surface. These shall be of required size and thickness. 9.15.26.1.1 Hinge Pin: Hinge pin shall be made of 5.5 mm dia stainless steel. It shall fit inside the knuckles firmly and riveted head (head covered with same material as of hinge) shall be well formed so as not to allow any play or shake and shall allow easy movement of the hinge, but shall not cause looseness. 9.15.26.1.2 Knuckles : The number of the knuckles in hinges shall be as per IS 1341. The shape of knuckles shall be straight and right angle to flap. The movement of the hinge shall be free and easy and working shall not have any play or shake. 9.15.26.1.3 Screw Holes : The screw holes shall be clean and counter sunk. These shall be suitable for counter sunk head cross head wood screws and of the specified sizes for different type and sizes of hinges. The size of the holes shall be such that when it counter sunk it shall be able to accommodate the full depth of counter sunk of screws. 9.15.26.2 P.T.M.T. Door Handles : The door handles shall be of material as mentioned in para 9.15.26.0 above moulded to required shape and size. The size & thickness etc. of the handle shall be determined by the inside grip of the handle. These shall be moulded as solid sections. The body of the handle shall not be hollow. Door handles shall be 100 mm size and window handles of 75 mm size unless, otherwise specified. These shall be fixed with 25 mm long wood. (Cross head) screws of designation No. 6. 9.15.26.3 PTMT Tower Bolt : The tower bolt shall be generally barrel type of material as mentioned in para 9.15.26.0 moulded to required shape and size. Size (length, dia, length of rod, number of holes) shall generally confirm to IS 204 PI & P-II. The rod shall be solid. If it in hollow it shall be provided with stainless steel rod of required dia. for its strength protective coat of wood primer, polish or varnish. 9.16 LAMINATED VENEER LUMBER (LVL) 9.16.1 Laminated Veneer Lumber door frames and shutters shall conform to IS 14616. 9.16.2 Material 9.16.2.1 Laminated Veneer Lumber (LVL) (a) Laminated Veneer Lumber is made of rubber wood silver oak, eucalyptus, Poplars, acacias etc. veneers glued together having grains of all the veneers in one direction under high temperature and pressure to develop high Modulus of Repture & Modulus of elasticity. Veneers for LVL shall be of thickness between 1.5 to 2.5 mm. (b) Veneers shall be free from knot holes, decayed knots except pin knots, unfilled splits wider than 3 mm, concentrated borer holes, shakes, objectionable decay or termite attack, except that for the face veneers none of these defects nor cross grain exceeding 1 in 10 shall be permitted. The nominal thickness of all the veneers used shall be identical and uniform within a tolerance of + 5 percent. CPWD SPECIFICATIONS 2009

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(c) Adhesives : Only BWP grade adhesive conforming to IS 848 shall be used for making LVL. (d) Preservatives : Veneers used for LVL shall be given suitable perservative treatment before lamination, with a preservative that is compatible with the adhesive to be used. Only fixed type of water soluble preservatives, CCA or CCB, or non-leachable, solvent soluble preservatives as per IS 401 shall be used for treating the veneers. Retentions of preservatives shall be as per IS 401 depending upon the proposed end use. All the Veneers shall be given preservative treatment by one of the water soluble fixed type treatment, Copper Chrome-Boron Composition. (CCB) as per IS 401. The treated Veneers shall then be dried having moisture content less than 6%. The Veneers shall be glued together, by keeping all the grains in one direction, with BWP grade synthetic resin adhesive conforming to IS 848. The Veneers having moisture content less than 6% so glued, shall be pressed in hot press at high temperature of 140 degree C to 180 degree C. and pressure 1.4 to 1.8 MPa. The net absorption of preservative in LVL when tested as per IS 2753 shall not be less than 8.0 kg/m3 Veneers shall be scarf jointed only length wise and not in the direction of width with EWP type synthetic resin adhesive. However, the length of individual Veneer shall not be less than 600 mm. 9.16.3 Moisture Content The average moisture content of three test specimens, when determined in accordance with IS 1734 (Part 1) shall be between 5 to 15%. 9.16.4 Tests 9.16.4.1 The tests as per Table-1 of IS 14616 shall be carried out by the manufacturer on the LVL (Laminated Veneer Lumber) sections on each batch. 9.16.4.2 The manufacturer shall get the tests done on at least three samples of each batch by the standard method of test to ensure quality and performance of the material as per para 8.2 of IS 14616. 9.16.4.3 The manufacturer shall provide a certificate with the delivery challan indicating that the material conforms to IS 14616 along with the copy of the test report of the relevant batch. 9.16.5 Laminated Veneer Lumber (LVL) Door Shutters (Fig. 9.16) 9.16.5.1 This specification lays down requirements regarding types, sizes, material, construction, workmanship and finish, performance evaluation, sampling, measurements, rates and testing of Laminated Veneer Lumber (LVL) door shutter for use in domestic buildings, offices, schools, hospitals etc. This specification does not cover large size door shutters for industrial and special buildings such as workshops, garages, godowns etc. 9.16.5.2 The material of each lot shall be supported by a certificate to that effect: Each lot of LVL materials shall be accompanied by the test reports. Fabricator shall take up manufacturing of shutters only if provisions of clause 9.16.4 are fulfilled; failing which, shutters so manufactured are liable for rejection. 9.16.5.3 Panelling Materials 9.16.5.3.1 Plain Particle Board: Plain particle boards used for panels shall be FPT-1 conforming to IS 3087 and shall have been bonded with BWP type of synthetic resin adhesive as per IS 848. (Ref. para 9.2.3) 9.16.5.3.2 Pre-laminated Particle Board: Pre-laminated particle boards used for panels shall conform to IS 12823. The plain particle boards used in pre-laminated particle boards shall be as per para 9.2.11 above. 341

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9.16.5.3.3 Medium Density Fibre Board: Medium density fibre board used for panels shall conform to exterior grade as per IS 12406 made from agro-forest products or agricultural wastes or natural fibers. 9.16.5.3.4 Pre-laminated Medium Density Fibre Board: Pre-lamination in pre-laminated medium density fiber board shall conform to the requirements such as Abrasion Resistance, Resistance to Steam, Crack Resistance, Resistance to Cigarette Burn and Resistance to Stain as specified in IS 12823. The medium density fibre board used in pre-laminated medium density fibre board shall be as per para 9.6.11 above. 9.16.5.3.5 Glass: Glass for glazing shall conform to IS 2835 or IS 2553. The use of other types of glass, such as frosted glass, wired glass and coloured glass may also be specified by the Engineer-inCharge. (Ref.para 9.2.8). 9.16.5.3.6 Wire Gauze: Wire gauze shall generally conform to IS 1568 and shall be regularly woven with equally spaced galvanized mild steel wires of 0.63 mm nominal diameter in both warp and weft directions to form aperture of average width 1.40 mm. (Ref para 9.2.9) 9.16.6 Construction and Workmanship 9.16.6.1 Laminated Veneer Lumber (LVL) panelled, glazed and panelled and glazed shutter shall be constructed in the form of LVL framework of stiles and rails with panel inserts conforming to para 9.16.5 above of plain or perlaminated particle board, plain or prelaminated medium density fibre board, wire gauze or glass. The panels shall be fixed by either providing grooves in stiles and rails and beading as specified. The stiles, top rails, lock rails and bottom rails shall be jointed to each other by mortice and tenon joints (See Fig. 9.16A). Rails having width of 150 mm or more shall have plain double tenon joints as shown in Fig. 9.16B. Other rails shall have single tenon joints. The bottom lock and top rails shall be inserted 25+3 mm short of the width of stiles to form a stub mortice & tenon joint. After assembling shutter complete with panels, Bamboo pins of 6 mm dia shall be fitted on each tenon & mortice joint by drilling suitable size of holes (2 pins per joint for rail width upto 150 mm and 3 pins for rails of greater width). All the four edges of shutter shall be beaded with 12 mm thick rubberwood /plantation wood lipping (See Fig. 9.16). Lipping shall be seasoned and chemically treated as per clause 9.16.4. Lipping on top and bottom rails shall be of one piece and lipping on stiles may be in two pieces. All lippings shall be glued to shutter with water resisting glue (Synthetic rubber passed adhesive) at the rate of 0.15 kg/m2. 9.16.6.2 All members of the shutters shall be straight, smooth and with well planed faces at right angles to each other. Any warp or bow shall not exceed 1.5 mm. The right angle for the shutters shall be checked by measuring the two diagonals from one extreme corner to the opposite one and the difference between the two diagonals shall not be more than 3 mm. 9.16.6.3 Beading: All the panels except glass and wire gauze shall be fixed with grooves (see Fig. 9.16C) but additional beading may be provided either on one side or on both the sides, if so specified. In so far as glass and wire gauze panels are concerned, beading shall be provided without grooves. In such a case where beading is provided without the grooves, the beading shall be only on one side, the other side being supported by rebate from stiles. The beading shall have a size not less than 15 mm x 10 mm. It can be fixed by suitable headless nailing or screwing. The beading shall be of plantation timber section, preservative chemically treated of fixed type as per IS 401-1982. 9.16.6.4 Stiles, top rails, bottom rails and lock rails of shutters shall each be made in one piece of LVL, only. Mullions and glazing bars shall be stubtenoned to the maximum depth which the size of the member would permit or to a depth of 25 mm, whichever is less.

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Two common methods for jointing of panels with stiles/rails are shown in Fig. 9.16C. The minimum depth of grooves of stiles and rails shall be 12 mm for all types of panelling. The panels shall be framed into grooves to the full depth of groove leaving an air space of 1.5 mm and the faces shall be closely fitted to the sides of the groove. LVL Shutters shall be manufactured in factories under controlled conditions. 9.16.7 Panelling 9.16.7.1 Plain and Prelaminated Particle Board Paneling: The panels shall be made of one piece of plain or prelaminated particle board of thickness 12 mm or more. 9.16.7.2 Wire Guaze Panelling : Wire guaze panel shall be so designed that no single panel shall exceed 0.5 sqm. in area. 9.16.8 Rebating In case of double leaved shutters, the meeting of the stiles shall be rebated either splayed or square type as shown in Fig. 9.16 D as per clause 6.12 of IS 1003 (part-1). 9.16.9 Gluing of Joints The contact surfaces of tenon and mortice shall be treated before putting together as per clause 6.13 of IS 1003 (Part-I). All the tenon and mortice joints should be glued together and pinned to full thickness of the door with Bamboo pins. 9.16.10 Dimensions, Sizes and Tolerances 9.16.10.1 Dimensions of Components and Tolerances: The finished dimensions and tolerances of the different components of door shutter shall be as per para 9.6.1.4.1. Tolerances: Tolerance on the size of door shutter shall be + 3 mm and in thickness + 1.2 mm. 9.16.11 Locations of Fittings and Accessories 9.16.11.1 Each door shutter shall be fixed to the frame with four hinges, unless otherwise specified by the Engineer-in-Charge, of the type specified. The lock rail of door shutters, where provided, shall be so placed that its centre line is at a height 850+5 mm from the bottom of the shutter. Hinges and other fixtures shall be fixed to shutter with full threaded steel screws after coating the screws with adhesive such as fevicol etc. For fixing of hinges, holes of 3.5 mm diameter and 52 mm length shall be bored and No. 10 full threaded parallel shank steel screws, 50 mm long, coated with adhesive shall be used. In no circumstances screws shall be hammered into board. 9.16.11.2 Cleats and blocks made of LVL wood shall be fixed to door shutter, if required, by the user as per size and shape approved. Pull bolt or sliding door bolt etc. shall be provided in the door shutter at a height of 850 mm from bottom of shutter. These shall be fixed to shutter as per method of fixing described in 9.16.11. For rescrewing, a plastic sleeve of appropriate diameter shall be inserted into the hole and then fixing with full threaded screws shall be done. Fittings other than hinges shall be provided as per schedule of fittings decided by the user. The fittings shall conform to specifications as described in clause 9.15. 343

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Panelled shutter may be provided with louvers of vision panels as specified. Where such a provision is made, the position, sizes and shape of louver or vision panel opening shall be as specified. 9.16.12 Finish All the four edges of the shutter shall be square. The shutter shall be free from twist or warp in its plane. Panels of the door shutters shall be flat and well sanded to a smooth and level surface. All the surfaces shall be delivered without protective coat of wood primer polish or varnish. 9.16.13 Glazing 9.16.13.1 Glazing in the shutters of door and window shall be as per sub head 21.0 In specifying sizes of the openings or panels of glass, the first dimension shall be width. The glass shall be embedded in putty and secured to the rebate by the wooden beading of suitable size and shape. 9.16.14 Tests 9.16.14.1 Routine Tests: The following test shall be carried out by the fabricator on shutters during the process of fabrication in the factory’s laboratory to be developed for this specific purpose before dispatch of shutters. TABLE 9.21 Sl.No. 1. 2. 3. 4.

Name of Test Dimensions and Defects of Squareness Test General Flatness Test Local Planeness Test Flexure Test

Acceptability Criteria As per IS 4020 As per IS 4020 As per IS 4020 As per IS 4020

9.16.14.2 Type Test : The manufacturer shall also have the performance of the shutters tested as per IS 4020 by the following tests as given in Table 9.22. TABLE 9.22 Sl.No. 1. 2.

6.

Name of test Impact indentation test Screw withdrawal /Holding power test (a) Face (Min) (b) Edge (Min) Edge loading test (a) Deflection (b) Residual Deflection Shock resistance test (a) Soft & light weight body impact (b) Soft and heavy weight body impact Buckling test (a) Deflection/Deformation (b) Residual Deformation Misuse test

7.

Slamming test

3.

4.

5.

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Acceptability Criteria Not more than 0.2 mm 2700 N 2300 N Not more than 5 mm Not more than 0.50 mm No visible damage observed -doNot more than 50 mm Not more than 5 mm Not be any permanent deformation observed No visible damage observed

(i) All the tests to be carried under 9.16.14 shall be got done through approved/reputed lab on at least three samples to ensure the quality and performance of the door shutters on completing manufacturing of 5000 door shutters or once in 12 months whichever is earlier. Record of manufacturing of shutters shall be maintained to ensure the required frequency. The fabricator shall also provide a certificate of shutters conforming to these specification along with each lot. The fabricator shall also provide test reports carried under para 9.16.14.1 and 9.16.14.2 with each lot of supply. (ii) Tests to be conducted by field units : The Engineer-in-Charge shall also have options to get any or all other test covered in 9.16.14 done at his own cost. If the shutter fails to satisfy the test, cost will be borne by the supplier and consignment shall be rejected. 9.16.15 Measurement Length and width of the shutter shall be measured to the nearest centimetre in closed position covering the rebates of the frames but excluding the gap between the shutter and the frame. Overlap of the two shutters shall not be measured. All work shall be measured net as fixed and area calculated in square metres to nearest two places of decimal. No deduction shall be made to form panel opening, louver Venetian opening and opening for glazing. No extra payment shall be made for shape, joints and labour involved in operations described above. 9.16.16 Rates The rate includes the cost of material and labour involved in all the operations described above. Extra rate shall be payable for providing rebates in double leaf shutters. Fittings described in 9.16.11.2 shall be payable extra. Nothing extra shall be payable for complying with the provisions described in 9.16.14.1 & 9.16.14.2. Cost of tests as described in 9.16.14.2 shall be borne by Deptt. if test reports are found satisfactory. Rate shall include cost of material and labour involved in providing plain beading. Extra shall be paid for providing moulded/plain beading on panels where specified. 9.17 PARTITIONS 9.17.1 (i) (ii) (iii)

Materials Gypsum Board conforming to IS 2095 (Pt.-I) Non asbestos multi-purpose cement board conforming to IS 14862 Tapered edge calcium silicate board

Tapered Edge Calcium Silicate Board are manufactured from Siliceous and Calcareous materials reinforced with fibers. The boards are made in a laminar process and then autoclaved to give a stable crystalline structure. It is lightweight and can be fixed to either side of timber, aluminum or lightweight galvanized metal sections. The partitions are non-load bearing and can easily be assembled at site. 9.17.2 Installation The G.I. frame and board partitions shall be fixed as per nomenclature of the item and directions of Engineer-in-Charge. (Fig. 9.17). 9.17.3 Jointing & Finishing Joints of the boards are finished with specially formulated Jointing compound and fibre tape to provide seamless finish. Board surface can be decorated with any type of paint, wall paper, wood veneer & hard laminates. Services should be incorporated before commencement of board fixing. 9.17.4 Fitting and Fixtures It is easy and simple to attach different fittings to wall panelling boards. Inclined nails can be fixed to the boards itself for light materials. For heavier materials the fastening should be centered on internal stud work or steel or wood frame behind the boards, fixed before boarding. Services should be incorporated before commencement of board fixing. 345

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9.17.5 Tolerance Tolerance in dimensions shall be + 5 mm. 9.17.6 Measurements 9.17.6.1 Length and breadth of superficial area of the finished work shall be measured correct to a cm. Area shall be calculated in square meter correct to two places of decimal. No deduction will be made of openings of areas upto 0.40 sqm nor shall extra payment be made either for any extra material or labour involved in forming such openings. 9.17.6.2 For openings exceeding 0.40 sqm. in area, deduction in measurements shall be made but extra will be payable for any extra material or labour involved in making such openings. 9.17.7 Rate The rate shall include the cost of all materials and labour involved in all the operations described above including all scaffolding, staging etc. 9.18 UPVC- DOOR FRAMES 9.18.0 Material Polyvinyl chloride Resin suspension grade is the basic raw material for forming PVC compound. PVC resin then is mixed with chemicals like Calcium, Stearate, Hydrocarbon Wax, Titanium Dioxide, Calcium Carbonate, Acrylic processing aids. Further, additives like impact modifiers, pigments, epoxy plasticizer, UV stabilizer, lubricants, chemical blowing agent etc. are added. The purpose of adding the chemicals and additives is to impart cellular structure, strength, surface finish, colour and resistance to fading by light rays. These chemicals are mixed in the desired proportion and shall be used in the formulation of PVC material and for free and smooth extrusion of PVC profiles. 9.18.1 UPVC Door Frame UPVC door frame shall be made of PVC material conforming to IS 10151. The door frame shall be made from extruded UPVC section having overall dimensions of 48 x 40 mm or 42 x 50 mm having wall thickness of 2.0 mm + 0.2 mm. Corners of the door frame to be jointed by M.S. galvanized brackets. Joints mitred and plastic welded. The hinge side vertical outer frames shall be reinforced by galvanized M.S. Tube of size 19 x 19 mm of wall thickness 1 mm + 0.1 mm and a tie rod shall be provided at the bottom of the frame. The frame shall be fabricated in factory as per nomenclature of the item and directions of Engineer-in-Charge. (Fig. 9.18). 9.18.2 Fixing of Frames The frames are to be fixed in prepared openings in the walls. All civil work and tiling should be completed before the fixing of the frames. The frames are to be fixed directly on the plastered wall. In case tiling is to be done in the place the frames are to be fitted, a 50 mm strip should be left untiled at the location where the frames are to be fitted. The frames are erected in the prepared opening such that the vertical members of the door frame are embedded 50 mm in the floor. The frame shall be fitted truly in plumb. A minimum of three anchor bolts or screws of size 65/100 shall be used to fix each vertical member. One bolt shall be fixed at 200 mm from the top member and one bolt shall be fixed at 200 mm from the floor. The third anchor bolt shall be fixed in the center. The top horizontal member shall be fixed using two 65/100 size anchor bolts or screws at a distance of 200 mm from both the corners. 9.18.3 Measurements The outer length of the vertical and horizontal members of UPVC door frame shall be measured in running metres including embedded length in floor corrected upto a cm. 9.18.4 Rate The rate includes the cost of the materials and labour involved in all the operations described above. The cost of anchor bolts or screws for joining the frame is included in the rate. Any other hardware, which may be required, shall be paid for separately. CPWD SPECIFICATIONS 2009

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9.19 PVC DOOR SHUTTERS The shutters shall be fabricated at factory as per nomenclature of the item and directions of Engineer-in-Charge. Shutter shall be made of PVC material conforming to IS 10151. 9.19.1 24 mm thick PVC Door Shutter (Fig. 9.19) 9.19.2 30 mm Thick PVC Door Shutters (Fig. 9.20) 9.19.3 Sampling and Criteria for Conformity 9.19.3.1 General Precautions 9.19.3.1.1 The test specimens shall not have been exposed to a temperature below 40oC for 24 hours immediately preceding the test and shall be free from all visible moisture. The specimen shall be inspected and any specimen with visible flaws shall be discarded. 9.19.3.1.2 If any test specimen fails because of mechanical reason, such as failure of testing equipment or improper specimen preparation, it shall be discarded and another specimen taken. 9.19.3.2 Sampling 9.19.3.2.1 Sampling criteria for conformity shall be in accordance with IS 4020 (Part –I) 9.19.3.2.2 Lot in any consignment of shutters shall be of the same grade and type and manufactured under similar conditions of production which shall be grouped together to form a lot. 9.19.3.2.3 The number of shutters to be selected at random from a lot shall depend upon its size and shall be in accordance with Col. 1 and Col. 2 of Table 9.23. TABLE 9.23 No. of Sample and Criteria for Conformity Sl. No. (1) 26 to 50 51 to 100 101 to 150 151 to 300 301 to 500 501 and above

Sample size (2) 8 13 20 32 50 80

Permissible No. of Defects (3) 1 1 1 1 2 2

Note : For lot size 25 or less, number of samples to be taken for testing shall be as agreed to between the manufacturer & Engineer-in-Charge. Number of Tests : The samples selected as in column 2 of Table 9.23 shall be as agreed to between the manufacturer & Engineer-in-Charge. 9.19.3.2.4 Criteria for Conformity : The lot shall be considered conforming to the requirements if the number of samples failing to satisfy the requirements of characteristics does not exceed the permissible number mentioned in col. 3.

347

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9.19.4 Test 9.19.4.1 The door shutters shall be subjected to the following tests in accordance with IS 4020 (Part 1 to 16). (a) Dimension and Squareness Test : Door shutters when tested in accordance with IS 4020 (Part 2) the dimensions of nominal width and height will be within a limit of + 5 mm. The door shutter shall not deviate by more than 1 mm on a length of 500 mm. The thickness of the door shutter shall be uniform throughout with the permissible variation of not more than 0.8 mm between any two points. The nominal thickness of the shutter shall be within a limit of + 1.5 mm. (b) General Flatness Test : Door shutter, when tested in accordance with IS 4020 (Part 3) the twist, cupping and warping shall not exceed 6 mm. (c) Local Planeness Test : Door shutters, when tested in accordance with IS 4020 (Part 4), the depth of deviation measured at any point shall not be more than 0.5 mm. (d) Impact Indentation Test : Door shutters, when tested in accordance with IS 4020 (Part 5), shall have no defects such as cracking, tearing or delamination and the depth of indentation shall not be more than 0.2 mm. (e) Edge Loading Test : Door shutters, when tested in accordance with IS 4020 (Part 7) the deflection of the edge at the maximum load shall not be more than 5 mm. On removal of the loads, the residual deflection shall not be more than 0.5 mm, failing which the test may be repeated on the other edge in the reverse direction. Also there shall be no lateral buckling by more than 2 mm during loaded condition and no residual lateral buckling after removal of the load. (f) Shock Resistance Test : Door shutters, when tested in accordance with 2.1 of IS 4020 (Part 8) , there shall be no visible damage in any part of the door after twenty five blows on each end. (g) Buckling Test : Door shutters, when tested in accordance with IS 4020 (Part 9), shall not show any deterioration and any residual deformation more than 5 mm after 15 min. of unloading and the initial deflection also shall not be more than 50 mm. (h) Slamming Test : Door shutters, when tested in accordance with 2.1 of IS 4020 (Part 10), shall not have any damage in any part of the door at the end of successive impacts. Door shutters, when tested in accordance with 3.1 of IS 4020 (Part 10), shall not have any visible damage in part of the door at the end of 100 successive impacts. (i) Misuse Test : Door shutters, when tested in accordance with IS 4020 (Part 11), there shall not be any permanent deformation of the fixing or any other part of the door set in hindering its normal working after the test. (j) Screw Holding Test : Door shutters, when tested in accordance with IS 4020- Part 16, the load shall not be less than 1000 N. (k) End Immersion Test : Door shutters, when tested in accordance with IS 4020- Part 13, the shutter shall not show any delamination. (l) Knife Test : Door shutter, when tested in accordance with IS 4020 – Part 14, the grading shall be standard & excellent. (m) Glue Adhesion Test : Door shutters shall be tested in accordance with IS 4020 – Part 15. There should be no delamination. CPWD SPECIFICATIONS 2009

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9.19.5 Fixing of Shutters PVC door shutter shall be side hung on three bolt hinges of size 100 mm, one at the centre and the other two at 200 mm from the top and bottom of the shutter. The flat of the hinges shall be neatly counter sunk in to the recesses cut out to the exact dimensions of the hinge flap. The door shall be drilled on the thickness to fit hinges. Screws for fixing the hinges shall be screwed in with screwdrivers and not hammered. The length of the screws should be 8 mm/30 mm. The hinges used should be of stainless steel. 9.19.6 Tolerance The tolerance on the width and the height of the door shall be + 5 mm and the tolerance on the nominal thickness of the door shall be + 2 mm. 9.19.7 Fittings Fittings shall be provided as per schedule of fittings decided by Engineer-in-Charge. In moisture prone areas M.S. fittings and screws should not be used. Hardware such as handles, tower bolt, stopper, buffer etc. should be directly screwed (not pre-drilled) and fitted on the door. 9.19.8 Measurements Length and width of the shutters shall be measured to the nearest cm in closed position covering the rebates of the frames but excluding the gap between the shutter and the frame. Area is calculated to the nearest 0.01 sqm. 9.19.9 Rate The specified rate include the cost of the door shutter and labour involved in fixing of the shutter. Fittings & fixtures on the door shutter except hinges & screws shall be paid extra as provided. 9.20 PVC DOOR FRAME Solid PVC door frame and shutter shall be as per para 9.19. 9.20.1 Solid PVC Door Frames consisting of section 50 x 47 mm shall be fabricated from 5 mm PVC sheet having density of 600 kg./cum. The sheet used may be in plain colour, printed design or prelam veneer shade as approved by the Engineer-in-Charge. The weight per running metre of the door frame including reinforcement should be a minimum of 1.5 kg./sq. mtr. The depth of the rebate of door frame shall be 10 mm. Frames shall have smooth surface, without any warping or bending in any member. All the parts of the door frame are to be joined to each other using solvent adhesive conforming to IS 14182. A tolerance of + 3 mm shall be permitted in the specified dimension of PVC section in the door frames. (Fig. 9.21) The solid PVC door frames shall be fabricated in factory as per nomenclature of the item and directions of the Engineer-in-charge. 9.20.2 Fixing of Frames As per clause 9.18.2. 9.20.3 Measurements As per clause 9.18.3. 9.20.4 Rate As per clause 9.18.4. 9.21 PANEL PVC DOOR SHUTTER 9.21.1 Panel PVC Shutters are factory made shutter and shall be brought to site fully assembled. The Solid Panel PVC Door shall be fabricated from 5 mm PVC sheet. The sheets used may be in plain colour, printed design or prelam veneer shade as approved by the Engineer-in-Charge. The shutters shall be fabricated at factory as per nomenclature of the item and directions of the Engineer-in-charge. (a) 30 mm thick panel PVC door shutters (Figure 9.22). 349

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

9.21.2 Sampling and Criteria for Conformity As per clause 9.19.3. 9.21.3 Tests As per clause 9.19.4 except para (k), (l) & (m). 9.21.4 Fixing of Shutters As per clause 9.19.5. In addition, it may be ensured that while fixing hinges the screws pass through the two opposites surfaces of the M.S. reinforcement. 9.21.5 Tolerance As per clause 9.19.6. 9.21.6 Fittings As per clause 9.19.7. 9.21.7 Measurements As per clause 9.19.8. 9.21.8 Rate As per clause 9.19.9. 9.22 FIBRE GLASS REINFORCED PLASTIC (FRP) DOOR FRAMES 9.22.0 Door Frames shall be three legged of cross section 90 mm x 45 mm having single rebate of size 32 mm x 15 mm to receive shutter of 30 mm thickness. The frame shall be made of laminate of thickness of 2 mm and shall be filled with wooden blocks of exterior grade MDF or seasoned and treated hard wood inside the laminate in all the three legs of the frame. The frame to be moulded by either hand lay up or resin transfer moulding process. The process shall consist of laying gelcoat at 1000 gms./m2 and laid over with layer of FRP Mat (CSM mat) gelcoat and FRP (CSM Mat) are defined in IS 14856. The CSM mat shall be bonded with Isophatholic resin in the ratio not less than 1:2 (One part of Mat to two parts of Isopathlic resin and fillers & additives) by weight. The edge shall be sealed with gelcoat and FRP mat to obtain smooth finish. Sufficient roving shall be laid in the corner to have smooth curve while laying the CSM mat. (Fig. 9.23). 9.22.1 FRP door shall be manufcturred as per specifications laid down in IS 14856, nomenclature of items & direction of Engineer-in-Charge. 9.22.2 Tolerance Tolerance of size of frame to be + 2 mm and on size of rebate to be + 1 mm. 9.22.3 Finish The surface of the moulded frame shall be free from any visible defects such as small pores, crazing, blistering, wrinkling, impurities, defective impregration, colour blots and aggregate defects, as mentioned in IS 14856. Scattered pin holes duly repaired and finished by applying resin and not noticeable shall be acceptable. Frame laminate shall be flat and shall have smooth and level surface. Laminate shall be finished in colour & shade as approved by Engineer-in-Charge. 9.22.4 Fixing of Frame As per clause 9.18.2. 9.22.5 Measurement As per clause 9.18.3. 9.22.6 Rate As per clause 9.18.4. CPWD SPECIFICATIONS 2009

350

9.23 FIBRE GLASS REINFORCED PLASTIC (F.R.P.) SHUTTERS 9.23.1 F.R.P. Shutters shall be manufactured conforming to the specifications as per IS 14856 and nomenclature of item & direction of Engineer-in-Charge. (Fig. 9.24A & 9.24B). 9.23.2 Blocks of any seasoned hardwood of bulk density not less than 450 kg./m3 at 12 per cent moisture content or any other material of sufficient thickness and length shall be provided inside the shutter at suitable place to hold fittings and fixtures such as aldrops, tower bolt, handle, sliding door bolt, mortice lock etc. Blocks for hinges shall be provided at three locations, unless otherwise specified by the purchaser. One at the centre and other two at 200 mm from the top and the bottom of the shutter. Blocks shall be provided at predetermined places in the shutter so as to fix hinges mortice locks, tower bolts, aldrops, door closures, etc. The finished surface shall be buffed and polished with wax. 9.23.3 Location of Fittings and Accessories The lock rail of door shutters shall be so placed that is centre line is at a height 850 + 5 mm from the bottom of the shutter. Door shutter shall be fixed to the frame with three hinges, unless otherwise specified by the purchaser, of the type specified. These locations shall be, one at centre and other two at 200 mm from the top and the bottom of the shutter, where blocks have already been provided and suitable indication by depressing the profile has been made. Screws for fixing the hinges shall be screwed in with screwdrivers & not hammered. The length of screw should be 8/30 mm. The hinges used shall be stainless steel or aluminum. 9.23.4 Sampling & Criteria for Conformity Shall be as per clause 9.19.3. 9.23.5 Finish As per clause 9.22.3. 9.23.6 Tests As per para 9.19.4 except clause (j), (k), (l) & (m). 9.23.7 Fixing of Shutter As per clause 9.19.5. 9.23.8 Tolerance As per clause 9.19.6. 9.23.9 Measurement As per clause 9.19.8. 9.23.10 Rate As per clause 9.19.9. 9.24 SOLID PVC FOAM PROFILE DOORS 9.24.1 Solid PVC Foam Profile Frame Solid PVC foam profile frame doors are made from solid PVC foam profiles 60 x 30 mm with integral skin cut to required size. Doors are provided with naturally strong stiffener frame and sandwich panelled to offer sound and heat insulation with pressure laminate/infill panel to provide scratch resistance surface. (Fig. 9.25). Supporting bar at bottom side of frame shall be provided for maintaining frame in plumb. The frame shall be fabricated in factory as per nomenclature of the item and directions of the Engineer-in-charge. PVC door frame should have shore hardness more than 70. 9.24.2 Fixing of Frames As per para 9.18.2.

351

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

9.24.3 Test in PVC Foam Profiles Tests on PVC Foam Profiles shall be as per Table 9.24 below: TABLE 9.24 Sl. No.

Property

Test Method

Unit

Acceptable Value

1

Density (at 27°C)

ASTM D 792

gm/cc

0.5-0.7

2

Tensile strength at yield (B) Elongation at Break Tensile Modulus (Modulus of Elasticity) Impact strength (charpy Unnotched) Durometer Hardness Vicat Softening Point (at 10N Load) Flammability

ASTM D 638 ASTM D 638 ASTM D 638

PSI % N/Sq.mm

2000 20 200

ASTM D 256

ftIb/sq.In

7

DIN 53505 ASTM D 1525

Shore D C

70 75

3 4 5 6 7

UL 94

Self Extinguishing

9.24.4 Measurements As per clause 9.18.3. 9.24.5 Rate As per clause 9.18.4. 9.25 SOLID PVC FOAM SHUTTERS Solid PVC foam shutters are made from solid PVC foam profiles with integral skin. Doors are provided with naturally strong stiffener frame and sandwich panelled to offer sound and heat insulation with pressure laminate/infill panel provides scratch resistance surface. Door shutters can be nailed, screwed, drilled, glued, sawn lapped or welded just like wood and characterized by excellent screw holding strength (200 kgf.). 9.25.1 28 mm Thick Door Shutters Profile is cut in required length to make vertical & horizontal stile. Mitered cut joint are made using solvent based PVC adhesive & epoxy solvent. GI ‘C’ stiffner 39 x 19 x 19 or 40 x 20 x 19g. M.S. Pipe is fixed in the grooves made in frame. Telescopic polymeric corners are provided at corners for better rigidity. Infill panel 3 mm thick HPL sheet is fixed with csk screws of required size to the profile frame as specified. Mirror image of shutter frame is joined using solvent based PVC adhesive as well as csk type sheet metal screws of required size at four corners at top & bottom. Additional bonding strength is provided by using silicone sealant epoxy sealant at joints. Lock rail is provided by using PVC profile & ‘C’ type GI stiffener 40 x 10 in the groove & fixed with adhesive to frame & infill. Decorative corner moulding is fixed to impart elegant look. (Fig. 9.26) The fabrication shall be done in factory as per nomenclature of the item and directions of Engineerin-Charge. 9.25.2 Sampling and Criteria for conformity As per clause 9.19.3. 9.25.3 Tests As per clause 9.19.4. 9.25.4 Fixing of Shutters As per clause 9.19.5. CPWD SPECIFICATIONS 2009

352

9.25.5 Tolerance As per clause 9.19.6. 9.25.6 Fittings As per clause 9.19.7. 9.24.7 Measurements As per clause 9.19.8. 9.24.8 Rate As per clause 9.19.9. 9.26 FACTORY MADE FIBRE GLASS REINFORCED PLASTIC CHAJJA 9.26.1 F.R.P. chajja shall be 4 mm thick of required colour/size, design and drawing as approved. The chaja shall have smooth gradual slope curvature for easy drainage of water & shall be factory manufactured as per nomenclature of item & directions of Engineer-in-Charge. (Fig. 9.27). 9.26.2 (1) (2) (3) (4) (5) (6) (7)

Material Glass Fibre (chopped strand mat) shall be as per IS 11551 Unsaturated Polyester Resin shall be as per IS 6746 Surface Burning Characteristics of Building Material – ASTM E 84-77a Unsaturated Polyester Resin Gel coat shall be as per IS 6746 Curing Agents – Cobalt Napthanate and MEKP Test of products – IS 14425 Glass Fiber Roving – IS 11320

The F.R.P. chajja laminate shall be water and chemical resistant and shall have very high transit strength to weight ratio and high modulus of elasticity, good textile processing and excellent fiber reinforcement properties. The laminate shall have low coefficient of thermal expansion and a high thermal conductivity and high dielectric constants. The F.R.P. laminate shall be diversionally stable, shall have moisture and corrosion resistance. 9.26.3 Tolerance Tolerance of + 10 mm in overall size of FRP chajja is permissible. 9.26.4 Finish The F.R.P. laminate to be finished with polyurathene based or equivalent paint as final coat or gloss or mat followed by clear lacquer coat to get the shine of required shade. 9.26.5 Tests Frequency of tests as per direction of Engineer-in-Charge & tests to be conducted as per para 9.19.4. 9.26.6 Measurement and Rate The width and length to be measured in centimetres and area to be calculated as square metre correct upto two places of decimal. The rate includes cost of all the materials, labour scaffolding, fittings & fixing upto all heights etc. involved in operations described above, but excludes the cost of paint. 9.27 WALL PANELLING (Fig. 9.28) All specification same as per clauses 9.17.1 to 9.17.7.

353

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

APPENDIX A

TABLE FOR PERMISSIBLE DEFECTS FOR VARIOUS GRADES OF TIMBERS (Clause 9.1) Sl. No. (1) (i) (ii)

(iii)

Defects (2) Cross-grain Sound knots and live knots

Dead and loose knots (plugged)

(iv)

Pitch pockets or streaks

(v)

Sapwood

(vi)

Pin holes

(vii)

Worm holes

First Grade (3) Not steeper than 1 in 15 (i) Stiles and Rails

Second Grade (4) Not steeper than 1 in 10 (i) Stiles and rails

(a) Short Exposed Face: Not more than 15 mm size and not more than 1 knot/metre (b) Long Exposed Face- Not more than 15 mm size and not more than 1 knot/m. No knot shall occur within 20 mm of the edges

(a) Short exposed Face – Not more than 15 mm size and not more than 3 knots per stile and 1 knot per rail (b) Long Exposed Face- Not more than 20 mm size and not more than 3 knots per stile and 1 knot per rail

(ii) Panels – Not more than 20 mm size and not more than 2 knots/m2. No knot shall occur on edge of any component of a panel. (i) Stils and Rails – Not more than 10 mm size – centrally located and not more than 1 knot / m

(ii) Panels – Not more than 20 mm size and not more the 4 knot/m2. No knots shall occur on edge of any component of a panel.

(ii) Panels – Not more than 15 mm size and not more than 2 knots/m2. No knot shall occur on edges of any component of a panel. None

Total not exceeding 5 mm wide and 150 mm long per metre. (This restriction applies only to super group species). Permitted provided they are not in cluster None

(i) Stiles and Rails – Not more than 10 mm size, centrally located and not more than 3 knots per stile and 1 knot per rail. (ii) Panels – Not more than 15 mm size and not more than 4 knots/m2. No knot shall occur on edge of any component of a panel. Permissible except on exposed edges provided that they are clean and filled up with suitable putty or filler when pitch pockets or streaks are located on the exposed edges of the core, they shall be cut out and filled with piece of wood of similar species with grain running in the same direction. The piece shall be well glued. Total not exceeding 10 mm wide and 300 mm long per metre. (This restriction applies only to super group species). Permitted. Permitted provided they are not more than 10 mm in diameter and not more than one per metre and provided such worm holes are plugged with similar timber in such a manner that the pluging merges with the surrounding area both as to colour and grain.

Note : (i) Dead and loose knots are permitted only if they are suitably plugged. (ii) Knot shall not occur where hinges or locks are to be fixed.

CPWD SPECIFICATIONS 2009

354

APPENDIX B

DIFFERENT CLIMATIC ZONES FOR MOISTURE CONTENT OF TIMBER (Clause 9.1.6) 7 2°AFGHANISTAN 76°

68°

88°

84°

80°

92°

96°

36°

INDIA SHOWING DIFFERENT CLIMATIC ZONES FOR MOISTURE CONTENTS FOR SEASONED WOOD

Gilgit JAMMU AN D KASHM IR Srinagar 32°

KI PA

Leh

AN ST

C

HIMACHAL PRADESH PUNJAB Shimla Ch andigarh Dehrad un HARYANA Delhi

28°

UT

T

Barmer

I B

3 2°

I N

E

NE PA L

TA R

PR AD Agra Lu ES ck H no w Gwalior Ka npur

Bikane r RAJASTHAN Jaipu r Jodhp ur

H

A

IM ok KK angt SI G

T

Itanagar M SA NAGALAND S A Ko hima MEGHALAYA Shilong MANIPUR Imphal BANGLADESH la Aizwal A ga rta

Patna Bhagalpur Gaya BIHAR

I

Ahmedab ad

N

D

Jabalpu r Bhopal MADHYA PRADESH

Indore

ARUNACHAL PRADESH

28°

BHUTAN

24°

GUJARAT

36°

A

I

WE ST Durgapur BENGAL Calicutta

24 °

MIZORAM

R aipur Diu Daman

20°

Dadra & Nagar Haveli Bombay

Silvasa gpur MA HARASHTRA Na Pune

BAY OF BENGAL

Bijapur Pananji (Goa, Daman & Diu ) Goa

AN

Zone I Madras

Kavaratti

EP

IS .

Zon e III

PONDICHERRY

Zone IV

Madurai

I 72°

N 76°

D

Na rcondam Ireland (Ind ia) Barren Irelan d (Ind ia) Port B lair

AR OB S IC ND & N iSLA

E

Zone II



Trivandrum



Note 4 :

NOTE OF SHADING

TAMIL NADU

LA RA KE

K SH D W

16°

N MA DA AN

12°

Note 1 : Note 2 : Note 3 :

R DH

P A

SH DE A R

KA RN AT AK A Bangalore

LA

Vishakhap atnam

Hyderabad

ARABIAN SEA 16°

20°

Bhubaneshwa r

ORISSA

I

A

O

N

C

E 84 °

80°

A

N 88°

92°

Based upon Survey of India map with the permission of the Surveyor General of India. The territorial waters of India extend into the sea to a distance of twelve nautical miles measured from the appropriate base line. The boundary of Meghalaya shown on this map is as interpreted from the North-Eastern Area (Reorganisation) Act, 1971, but has yet to be verified. The administrative headquarters of Chandigarh, Haryana and Punjab are at Chandigarh.

355

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

APPENDIX C

MOISTURE CONTENT OF TIMBER (Clause 9.1.6) C-1 Moisture content of timber shall be checked for every 1 cum or part thereof by electrical moisture meters as per IS 287. C-2 Electrical moisture meters are of resistance type and shall be used when the moisture content is within a range of 8 to 25 per cent. When checking moisture content with electrical moisture meter, it shall be ensured that : (a) Timber is not hot or surface wet and the moisture gradient is not large due to wet cores. (b) Electrode probes are of adequate depth (not less than one-fifth the thickness of the timber). C-3 Sufficient number of reading at different positions are taken on each piece of timber to eliminate localised variations in surface moisture and species corrections are applied for the make of electrical resistance type moisture meter. C-4 If for any reason, whatsoever, the result of electrical moisture are not to be relied upon the moisture content shall be checked by the oven drying method. C-5 For checking moisture content by oven drying method, a complete test cross section, 12 to 19 mm long in the direction of timber grain, free from all defects shall be cut from each piece of timber selected for test as follows : (a) If weighing can be done immediately, the test section shall be cut from a point at least 45 cm from one end of the piece or from its centre. (b) In case cutting of test section from the piece is not permissible the moisture content in the whole section can also be determined by collecting a boring to a depth of half of the thickness of the piece by means of an auger, in a preweighed weighing bottle which should then be sealed properly. C-6 The test sections obtained above shall be weighed, immediately after cutting, on a balance the sensitivity of which is not less than 10 mg. They shall be dried in a ventilated, and preferably thermostatically controlled, oven at a temperature of 100°C to 105°C untill the weight is constant. The weight of the test section shall be deemed to have become constant if successive weighing at intervals of 2 to 5 hours do not differ from one another by more than 50 mg. The test weight shall be taken to be the oven dry weight of the test section. C-7 The percentage moisture content in the test section shall be calculated as follows : W1 – WO Moisture content (Per cent) = ——————— WO Where : W1 =initial weight of test section and WO = oven dry weight of test section

× 100

C-8 When moisture content of timber is checked by oven drying method, results of electrical moisture meter shall be ignored.

CPWD SPECIFICATIONS 2009

356

APPENDIX D

PHYSICAL AND MECHANICAL PROPERTIES OF PLYWOOD (Clause 9.2.2.6) D-1 Moisture content 5 to 15 per cent. D-2 Shear Strength Average Individual

Dry State 135 110

Resistance to Moisture 100 80

APPENDIX E

PHYSICAL AND MECHANICAL PROPERTIES OF FPT OR GRADED PARTICLE BOARD (Clauses 9.2.3.4 ) Sl. No. (i) (ii)

Linear expansion (swelling in water). 2 h soaking-percent (a) Length (b) Width Thickness, swelling, percent 2 h soaking Swelling in thickness due to surface absorption, percent Modulus of rupture, N/mm2 (a) Average (b) Minimum

(iv) (v) (vi)

(vii)

(viii)

(x)

Flat pressed Three layer multi layer and graded Grade- I Grade-II ± 10 ± 10

Density variation, percent Water absorption, percent (a) 2 h soaking (b) 24 h soaking

(iii)

(ix)

Properties

Modulus of elasticity, N/mm2 (a) Average (b) Minimum Tensile strength perpendicular to surface, N/mm2 (a) Upto 20 mm thickness (b) Above 20 mm thickness

10 20

40 80

0.5 0.5 8 6

0.5 0.5 12 9

15 13

11 10

2500 2250

2000 1800

0.45 0.40

0.3 0.3

0.2 0.15

-

1250 850

1 250 700

2

Tensile strength perpendicular to surface, N/mm (a) After cyclic test (b) Accelerated water resistance test2) Screw withdrawal strength, N (a) Face (b) Edge (for thickness >12mm)

1)

Cyclic Test— Specimen are immersed in water at 27 ± 2°C for a period of 72 h, followed by drying in air at 27 ± 2°C for 24 H and then heating in dry air at 70°C for 72 h. Three such cycles are to be followed and then the specimens are tested for tensile strength perpendicular to surface.

2)

Accelerated Water Resistance Test— Specimen are immersed in water at 27 ± 2°C and water is brought to boiling and kept at boiling temperature for 2 h. Specimen are then cooled in water to 27 ± 2°C and then tested for tensile strength perpendicular to surface.

357

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

APPENDIX F

TESTS FOR FLUSH DOOR SHUTTERS (Clause 9.7.1 to 9.7.10) F-1. END IMMERSION TEST Door shutters shall be tested for resistance of their base to immersion in water as follows : The door shutter shall be immersed vertically to a height of 30 cm in water at room temperature for 24 hours and then allowed to dry for 24 hours at 27 ± 2°C and relative humidity of 65 ± 5 per cent. The cycle shall be repeated eight times. There shall be no delamination at the end of the test.

25 cm

250 m m

( Appro x .)

F-2. KNIFE TEST (i) Apparatus : The type of knife required to be used in the test is given in Fig. below. It may be made from a 250 x 25 mm file. The cutting edge should be kept chiselsharp. The test shall be carried out on a stout table to which a wooden batten is screwed against which the edge of test piece is placed.

Drawing not to scale

KNIFE FOR TESTING PLYWOOD FOR ADHESION OF PLIES (ii) Procedure : The knife is inserted with its cutting edge parallel to the grain of the outer veneer and worked into, or if possible along a glue line and the veneer is prised upwards. A hard and dense specie of plywood requires considerable force to effect entry and to prise and veneer. In a soft timber the knife

CPWD SPECIFICATIONS 2009

358

tends to follow an easy course through the wood and in this case it is essential that the knife be firmly guided along the glue line. The bond should just pass the requirement, it is judged by the relative amount of wood fibre left on the core veneer, and the area prised off. The grading is assessed chiefly on the appearance of the break. The force needed to effect separation is also an accompanying requirement. The bond is ‘excellent’, when it is difficult to find the glue line and impossible to keep the tool within it for more than 6 mm without cutting adjacent wood. On prising upwards, the veneer usually breaks off over a width slightly greater than that of the tool. The bond is ‘poor’ when knife meets little opposition in the glue line and the prise results in the easy removal of almost all the veneers from one side of the test piece. The separated veneers are usually almost free from adherent fibre. (iii) Reporting of test results : The results shall be reported as ‘pass standard’ ‘excellent’ or ‘poor’. F-3. GLUE ADHESION TEST Four square sections, 150 x 150 mm shall be cut from the corners of the door. These four corner sections as cut from the door shall be immersed in boiling water for 4 hours, then dried at 27 ± 2°C and relative humidity of 65 ± 5 per cent for 24 hours. At the end of the drying period, the samples shall be examined for delamination. In the case of the glue lines in the plywood, all the four exposed edges of the plywood on both faces of a specimen shall be examined for delamination. A specimen shall be considered to have passed the test if no delamination has occured in the glue lines in the plywood and if no single delamination more than 50 mm in length and more than 3 mm in depth has occured in the assembly glue lines between the plywood faces and the stile and rail. Delamination at the corner shall be measured continuously around the corner. Delamination at a knot, knot hole, a pitch pocket and worm hole or other permissible wood defects shall not be considered in assessing the sample. A door shall be deemed to have passed this test if three of the four specimens tested pass the test.

359

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

APPENDIX G

TEST FOR MORTICE LOCKS (Clause 9.15.13) The finally assembled lock shall withstand the test given as below : The locking bolt shall be first locked in the forward position. A load of 40 kg. shall be applied without shock in the direction perpendicular to securing face as well as on both the locking faces of protruding bolt in turn. Then the load shall be applied by means of a fixed steel board 3 mm thick by rounded edge held in such a position that the centre line is approximately 3 mm from the fore end. A typical arrangement for the purpose of this test is shown in Fig. below : Fixed Bearer

Beam 75 cm Long Approx Lock

Fixed Block

Steel Bar 75 cm Long Approx.

Movable Weight 40 kg

Base

Fig. : Strength Test for Locking Bolt When the spindle with handle is inserted into hole in the follower and turned, the latch bolt shall draw smoothly into the lock body and shall be within one millimetre from the face of the fore end. When the latch bolt is pressed in to the lock body by pressure, the action shall be smooth and when fully pressed the latch bolt shall not project more than one millimetre from the face of the fore end. When a key is inserted in key hole from one side of the lock and turned to withdraw the locking bolt the action shall be smooth and without impediment. When the direction of turn is reversed to lock the locking bolt then also the action shall be smooth and without impediment. In the locked position the locking bolt shall project 12 mm from the face of the fore end, although one millimetre free movement is permissible. In the withdrawn position the locking bolt shall not project more than one millimetre from the face of the fore end. The locking bolt shall be worked by turning key in both the direction 6000 times. At the end of the test, the lock shall continue to work smoothly. The test shall be repeated with the key inserted from the other side of the lock. Note : The clearance for levers while in the operating condition shall not exceed 0.25 mm. When the key is turned to lock the locking bolt at the same time applying a reasonable pressure by finger on it, after completion of the key rotation the locking bolt shall be positively locked in the forward position. This test shall be repeated with the key inserted from the other side of the lock. CPWD SPECIFICATIONS 2009

360

APPENDIX H

SCHEDULE OF FITTING FOR DOORS AND WINDOWS (Clause 9.6.8) Single leaf wire guaze door shutters

Single leaf wardrobe/ cupboard shutters

Single leaf window shutters panelled or glazed

Fan light/ clear storey window shutters

Designation no. of wood screw

Length in mm of wood screws IS 6760

Remarks

4 3

Single leaf door shutters inter communicating panelled or glazed 5 3

6 3

7 -

8 -

9 -

10 9

11 40

12

-

-

-

-

-

2

2

8

20

Butt Hinges 50 mm

-

-

-

-

1

1

-

6

20

Piano Hinges Tower Bolt 250 mm Tower Bolt 150 mm Tower Bolt 100 mm Sliding door Bolt 300 mm Sliding door Bolt 250 mm Floor door stopper Door handle with plate 100 mm Window handle with plate 75 mm Casement stay 300 mm Helical door spring (Superior quality) Cupboard /Wardrobe Lock Fanlight Catch

3 1

2 -

3 -

2 -

-

1 1 -

-

6 10 8 6 9

20 30 30 30 35

-

1

-

-

-

-

-

9

35

2 2

1 2

1 2

1

1 -

-

-

9 6

30 25

-

-

-

-

-

1

-

6

20

-

-

-

-

-

1

-

6

30

-

-

-

1

-

-

-

6

30

-

-

-

1

1

-

-

6

20

-

-

-

-

-

-

1

8

30

Double leaf doors shutters panelled or glazed

Single leaf door shutters external panelled or glazed

3 6

2

2 Butt Hinges 100 mm Butt Hinges 75 mm

3

4 5 6 7 8

Sl. No .

Name of Fittings

1 1.

9 10 11 12 13 14 15 16

For fixing wooden cleat

Notes : A : Door Shutters 1. Door of room adjoining the verandah, corridor, lobby or hall, shall be considered as external door. 2. Where the height of the door leaf exceeds 2.15 metres above the floor level, one extra hinge shall be provided for every additional height of 0.50 metre, or part thereof and the length of top bolts shall be increased by the height of the leaf above 2.15 metres from floor level. 3. Single leaf door shutters of more than 0.80 m in width shall be provided with one extra hinge. 4. Fan light shutters of more than 0.80 metre width shall be provided with one extra hinge and extra quadrant stay. 5. In double leaf shutters of doors, two door bolts shall be fixed to the first shutter and one to the closing shutter at the top. 6. In case of single leaf inter communicating, panelled, glazed or panelled door shutter for bath and w.c. one tower bolts will be replaced by a bathroom latch. 7. For shutter exceeding 40 mm thickness, heavy type M.S. butt hinges of 125 x 90 x 4 mm shall be used. 8. In case of external door shutters, instead of sliding door ball mortice lock can be provided where specified. 9. Cupboard and wardrobe shutters will have ball catches where specified. 10. Finger plates shall be provided in case of bath and wc shutters in office buildings. B : Window Shutters 11. In case of windows with double shutters, two tower bolts shall be fixed to the closing shutters and one tower bolt to the first shutter at the top. 12. In case of window shutters, hooks and eyes may be provided in lieu of casement stays where specified. 13. Where the height of window shutter exceeds 1.20 metres one extra hinge shall be provided and length of top bolts shall be increased by height of the leaf above 2.15 metres from the floor level. 14. Window shutter with steel frames shall be provided with six hinges in case of double leaf shutters and three hinges in case of single leaf shutters, irrespective of height and width of shutters. C : Fanlight and Clerestory Window or Ventilator 15. Centrally hung and bottom hung CS windows and fan lights, will be provided with chain and hook bamboo pole with hook for opening ventilators shall be provided for each residence or for set of 4 rooms in case of office building. 16. Centrally hung clerestory windows or fan lights will have fan light pivots in lieu of hinges.

361

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

APPENDIX I

METHOD OF TEST FOR EDGE STRAIGHTNESS AND SQUARENESS OF PLYWOOD (Clause No. 9.2.8.3)

I.1 PROCEDURE FOR EDGE STRAIGHTNESS I.1.1 The straightness of the edge and ends of plywood shall be verified against a straight edge not less than the full length of the plywood. If the edge on the end of the plywood is convex, it shall be held against the straight edge in such a way as to give approximately equal gap at each end. The largest gap between the straight edge and the edge shall be measured to the nearest millimeter and recorded. I.2 PROCEDURE FOR SQUARENESS I.2.1 The squareness of plywood shall be checked with a 1200 mm x 1200 mm square by applying one arm of the square to the plywood. The maximum width of the gap shall be recorded.

APPENDIX J

METHOD FOR TEST FOR EDGE STRAIGHTNESS AND SQUARENESS OF COIR VENEER BOARD (Clause 9.2.10.6) J-1

PROCEDURE FOR EDGE STRAIGHTNESS

J-1.1 The straightness of the edges and ends of coir veneer board shall be verified against a straightedge not less than the full length of the coir veneer board. If the edge on the end of coir veneer board is convex, it shall be held against the straight edge in such a way as to give approximately equal gap at each end. The largest gap between the straightness and the edge shall be measured to the nearest millimeter and recorded. J-2 PROCEDURE FOR SQUARENESS J-2.1 The squareness of coir veneer board shall be checked with a 1200 mm x 1200 mm square, by applying one arm of the square to the coir veneer board. The maximum width of the gap shall be recorded.

CPWD SPECIFICATIONS 2009

362

APPENDIX K

METHOD OF TEST FOR COIR VENEER BOARD FOR DETERMINATION OF GLUE SHEAR STRENGTH (Clause 9.2.10.8 ) K-1 OBJECT K-1.1 This test is intended to estimate the tenacity with which the bonding material holds the coir veneer board together. K-2 TEST SPECIMEN K-2.1 Six test specimens shall be cut from the coir veneer board from three locations separated by the greatest possible distance from each other. K-2.2 The test specimens shall be prepared as shown in Fig. 1 below. K-2.3 The test pieces for 3 ply coir veneer board shall be prepared by gluing an additional 3 ply coir veneer board as shown in Fig. 1A below. The test pieces for 5 ply shall be prepared as shown in Fig. 1B below. The test pieces for 7 ply coir veneer board shall be prepared as shown in Fig. 1C below. The specimen is glued with room temperature setting epoxy resin and clamped/tied overnight. Note - This method of preparation of specimen will avoid the failure on notches. K-2.4 Before test, the specimen shall be conditioned to constant mass at relative humidity of 65 ± 5 per cent and at a temperature of 270o C ± 20oC. K-3 PROCEDURE K-3.1 Each test specimen shall be gripped symmetrically at two ends in the jaws of a suitable testing machine, and shall be pulled apart. The distance between the notches on the test specimen and the ends of the gripping jaws of the testing, machine shall be between 10 mm and 20 mm. The pull should be, as far as possible, in the centre line of the central veneer. The grain of the centre ply shall be perpendicular to the direction of application of load. The width of each specimen and distance between the notches shall be measured to nearest 0.025 cm. to determine the shear area. K-3.2 During the test, the load shall be applied to the test specimens as uniformly as possible, and so adjusted as to have the traverse of the movable head of 1 mm/min. K-3.3 The maximum load at the time of complete failure of each specimen shall be recorded. Record shall be made regarding the type of failure whether in ply or in glue by visual examination of the area under shear. In case of ply failure, the percentage ply failure shall also be recorded. K-4 REPORT K-4.1 Shear strength of the specimens determined in accordance with K-3 shall be straight averaged. K-4.2 All details shall be recorded under the following sub-heads. (a) Name of the manufacturer/source from whom the coir veneer board is procured (b) Type and grade of coir veneer board (c) Adhesive used (d) End use of coir veneer board (e) Specimen No. /Ref. (f) Area of cross-section of bonding surface under shear (g) Maximum load and (h) Percentage failure of glue/ply 363

contd......

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

APPENDIX K (Contd.)

25 ± 0.3

150 3

53

3

Veneer

Coir

25 ± 0.3

Reinforcement

25 ± 0.3

1A : 3-ply Test Specimen

25 ± 0.3

150

3

53

3

3

Veneer

Coir

25 ± 0.3

25 ± 0.3

1B : 5-ply Test Specimen

25 ± 0.3

150 3

53

3

Veneer

Coir

25 ± 0.3

25 ± 0.3

1C : 7-ply Test Specimen

Drawing not to scale All dimensions are in mm

Fig. 1 : Test Specimen for Glue Adhesion Test

CPWD SPECIFICATIONS 2009

364

JOINTS IN TIMBER Sub Head : Wood Work and PVC Work Clause : 9.0

A. TONGUE & GROOVE JOINT

B. MITRED JOINT

C. DOVETAIL JOINT

D. MORTISE & TENON JOINT

Drawing not to Scale

Fig. 9.1 : Joints in Timber

365

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

TERMINOLOGY TIMBER DOOR, WINDOW & VENTILATOR COMPONENTS Sub Head : Wood Work and PVC Work Clause : 9.6 A Width of Opening Head of Frame

Top Rail

DETAILS AT A

Hold Fast Glazed Panel

8 to 10 mm

Door Frame T/3

Stile Meeting Stile

T/3 T/3 45°

Lock Rail Wooden Panel Bottom Rail

Structural Floor Level

SPLAYED TYPE REBATE

8 to 10 mm

Finished Floor Level

T/2

Metal Pin

T/2

GLAZED AND PANELLED DOOR

SQUARE TYPE REBATE

Head of Frame Glass Panel Transome Hold Fast Glass Panel Stile

Bottom Rail

TOP HUNG VENTILATOR

CENTRE HUNG VENTILATOR

BOTTOM HUNG VENTILATOR

WINDOWS AND VENTILATORS Drawing not to Scale All dimensions are in mm

Fig. 9.2 : Terminology Timber Door, Window & Ventilator Components

CPWD SPECIFICATIONS 2009

366

WOODEN FLUSH DOORS SHUTTERS Sub Head : Wood Work and PVC Work Clause : 9.7 TOP RAIL Lipping Where Provided Stile

Cross Band

Face Veneer

BLOCK BOARD & PARTICLE BOARD CORE

PARTICLE BOARD CORE

Battens Battens

Equally Distributed Voids

Intermediate Rail Equally Distributed Voids

CELLULAR CORE

BLOCK BOARD CORE

HOLLOW CORE

Drawing not to Scale

Fig. 9.3 : Wooden Flush Doors Shutters

367

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

HOLD FAST Sub Head : Wood Work and PVC Work Clause : 9.13

40 20

100

100

Door Frame

Hold Fast

200 11 mm Hole

10

50

15

Nut & Bolt 10 mm dia

Wooden Plug

5

Enlarged Section of Bolt

50

Drawing not to Scale All dimensions are in mm

Fig. 9.4 : Hold Fast

CPWD SPECIFICATIONS 2009

368

C.C. Block

HINGES Sub Head : Wood Work and PVC Work Clause : 9.15.1 to 9.15.2 A

C

C D

D

B

Uncranked Cranked

Counter Sunk Holes

Knuckles

A. DIMENSION OF MEDIUM WT. MILD STEEL BUTT HINGES Size of Hinge

Length (A)

Breadth (B)

Thickness of Flap (C)

Dai of Hinge Pin (D)

No. of Knuckles

No. of Screw Holes

Holes for Screw No.

1

2

3

4

5

6

7

8

50 75 100

50 ± 0.5 75 ± 0.5 100 ± 0.5

37 ± 1 47 ± 1 58 ± 1

1.50 ± 0.06 1.70 ± 0.06 1.90 ± 0.06

3.15 ± 0.08 4.00 ± 0.08 5.60 ± 0.08

3 5 5

4 6 8

6 8 10

Min 7 A

C

D

Min 7 B

Kunckle

R6

Min 7 C

Counter Sunk Hole

B. PARLIAMENT HINGES

Drawing not to Scale All dimensions are in mm

Fig. 9.5 : Hinges

369

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

HINGES Sub Head : Wood Work and PVC Work Clause : 9.15.5, 9.15.6 A. TEE HINGES E D X X R

F

G B

X

C

A

DIMENSIONS Size

250 300

A

250 ±3 300 ±3

B

C

D

100 ±2 30 ±15 5.6 ±0.10 115 ±2 30 ±1.5 6.30 ±0.10

E

F

G

R

Screw Designation No.

No. of Holes in Strap

No. of Holes in Tee

2.24 ±0.10 2.26 ±0.10

45 ±2 50 ±2

40 ±1 50 ±1

8 ±1 8 ±1

9 9

5 5

3 3

Min 0.80 Max. 1.0 Thick

B. PIANO HINGES L2

L1

L1

B L3

L1

L1

2.5 mm φ Pin

L1 1825 ± 5

DIMENSIONS

Nominal Size 40 30

B 40 ± 1 30 ±1

L1 25 ± 2 75 ± 2

Drawing not to Scale All dimensions are in mm

Fig. 9.6 : Hinges

CPWD SPECIFICATIONS 2009

370

L2 25 ± 1 25 ± 1

L3 20 ± 1 15 ± 1

SLIDING DOOR BOLTS Sub Head : Wood Work and PVC Work Clause : 9.15.7 3.15

2.15

2

250

20±1 8 mm sq hole for Carriage Bolt

6.0±5 Bolt 60± 2

45 ±1

10.0±5 HASP

17.5±5 φ

100±2

17.5±5φ

Back Plate 40±1

CLIP 25±1 Bore to be Countersunk

12±1

3.15

27±1

11±5

17.5±5 φ

8±.5

12 sq ±1

8 sq Hole for Carriage Bolt

55 ±1

12± 0.5φ 50±2

Washer 40±1

Hex or Sq Nut

STAPLE MILD STEEL

C.I. BOLT A M F B E

C CAST TYPE

DIMENSIONS Size

A

B

C

E

F

M

Screw Designation No.

250 300

250 ± 2 300 ± 2

100 ± 2 100 ± 2

45 ± 1 45 ± 1

55 ± 1 55 ± 1

15 ± 1 15 ± 1

16.0 ± 0.5 16.0 ± 0.5

9 9

Drawing not to Scale All dimensions are in mm

Fig. 9.7 : Sliding Door Bolts

371

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

BARREL TOWER BOLTS Sub Head : Wood Work and PVC Work Clause : 9.15.8

B A

F

E

Y B G G Y

Screw Holes

C

SECTION YY

Spring and Ball

PRESSED

16

E+5 F

F

CAST OR EXTRUDED

DIMENSIONS Width of Barrel C When When D=10.0 D=12.00

Size

A

B

D

E

150

150+3 -1

170 + 3 -1

32+3 -1

38+3 -1

10 or 12 ± 0.5

25±1

200

200+3 -1

220+3 -1

32+3 -1

38+3 -1

10 or 12 ± 0.5

25±1

250

250+3 -1

270+3 -1

32+3 -1

38+3 -1

10 or 12 ±0.5

25±1

Thickness of Metal of Barrel Sheet F G Brass or Aluminium Sheet Mild Zinc Alloy Alloy Steel or When When Brass D=10.0 D=12.0 2.0 1.60 2.40 1.25 mm +0.5 ±10.33 ±0.36 ±0.15 1 to 1:5 -0.2 more than 2.0 1.60 2.40 1 to 1.25 dia of +0.5 ±0.33 ±0.36 ±0.15 bolt -0.2 2.0 +0.5 -0.2

1.60 ±0.33

Drawing not to Scale All dimensions are in mm

Fig. 9.8 : Barrel Tower Bolts

CPWD SPECIFICATIONS 2009

372

2.40 ±0.36

1 to 1.25 ±0.15

Screw Designation No.

8

8

10

PULL BOLT LOCKS Sub Head : Wood Work and PVC Work Clause : 9.15.10

Guide and 10 mm Plate 3 mm Thick 8 mm Round Head with Square Seal

6 mm Round Head Nut with Square Seat Door Frame

Shutter

Slide and Stop Block Iron Screw Open Position PLAN

ELEVATION 10 mm Dia bolt in Locking Position

Drawing not to Scale

Fig. 9.9 : Pull Bolt Locks

373

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

MORTICE LOCK & LATCH Sub Head : Wood Work and PVC Work Clause : 9.15.13 Locking Bolt Guide Pin Lever Spring Fulorum Pin

1

8 4

7

5

+2 5.5 -0

100 ±1

12 Min

6 Lever Pivot Pin

2

1 Body

3 Optional

Latch Spring Pivot Pin

Locking Bolt Body Cover

Size of Lock ASSEMBLED WITHOUT BODY COVER

25

12

16 4 Latch Bolt

Alternative Fixture for Face Plate

Locking Pin 25

25 2 Case Plate

6 Lever

Striking Plate 8 mm Square Hole for Connecting Rod

25 3 Face Plate Optional

7 Latch Spring

8 Follower

Drawing not to Scale All dimensions are in mm

Fig. 9.10 : Mortice Lock & Latch CPWD SPECIFICATIONS 2009

374

5 Locking Bolt

Key

MORTICE NIGHT LATCH Sub Head : Wood Work and PVC Work Clause : 9.15.16

Nominal Size (L) Case Plate

Face Plate (Optional)

Body

Spring

Fore End Right Latch

Locking Bolt

Levers

Follower

1

1.25 min

2

6

7

3

100

4

5

ASSEMBLY WITHOUT BODY COVER

BODY

BODY COVER

3

Square Hole

2 Follower Square Hole 3 Latch Spring 5 Locking Lug

10 6 Latch Bolt 25

8 25

15 min

4 Lever

7 Locking Bolt

1 CASE PLATE

Drawing not to Scale All dimensions are in mm

Fig. 9.11 : Mortice Night Latch

375

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

HANDLES FOR DOORS AND WINDOWS Sub Head : Wood Work and PVC Work Clause : 9.15.19

F D

C

E B X F

G

R3 3

C

A 1A

0.75

B

X

SECTION XX A

E F

H G

D B

Fig. 9.12.3 : Typical Door Handle (Type 3) F G E

A 1B C

Fig. 9.12.1 : Typical Door Handle (Type 1)

Fixing Arrangement

D

B C A

B

G H G Continuous Plate may be Provided where desired F

F E

Note : M5 x 20 mm G.I. Countersunk machine screw or any other suitable fixing arrangement may be used

E

Fig. 9.12.4 : Typical Door Handle (Type 4)

Fig. 9.12.2 : Typical Door Handle (Type 2)

Drawing not to Scale All dimensions are in mm

Fig. 9.12 : Handles for Doors and Windows

CPWD SPECIFICATIONS 2009

376

TABLE 2A DIMENSIONS OF DOOR HANDLES (Fig. 9.12.1 to 9.12.3) All dimensions in millimetres Type of Head

Ref to. Fig.

Sizes

A Min

B

C Min

D Min

E Min

F Min

G Min

H Min

I Min

Screw Holes* No. in Size Designation of Each Counter-sunk Head Lug Wood Screw (see # IS 6760-1972 )

(1)

(2)

(3)

(4)

(5)

(6)

(7)

(8)

(9)

(10)

(11)

(12)

(13)

(14)

9.12.1A

75 100 125 150

125 150 190 215

75 100 125 150

20 25 25 30

2.5 3.0 4.0 1.5

5 8 10 12

8 10 12 15

15 20 22 25

-

-

2 2 2 2

6 6 6 8

9.12.1B

75 100 125 150

85 110 140 165

75 100 125 150

20 25 25 30

2.5 3.0 3.0 4.0

5 5 7.5 7.5

8 10 12 15

15 20 22 25

-

-

2 2 2 2

6 6 6 8

2.

9.12.2

75 100 115 135

125 150 175 200

75 100 115 135

20 25 28 30

-

10 11 13 14

16 19 22 25

32 38 45 50

20 20 25 32

1.0 1.0 1.0 1.25

2 2 3 3

6 6 8 8

3.

9.12.3

75 100 75 20 5 14 16 8 1.25 90 125 90 25 6 16 20 10 1.25 100 150 100 28 7 18 25 12 1.60 More evenly spaced screw holes may be provided, if so required by the purchaser. Specification for slotted countersunk head wood screws.

1 2 2

6 6 6

1.

* #

TABLE 2B DIMENSIONS OF DOOR HANDLES All dimensions in millimetres. Type

Ref to Fig.

Sizes

A Min

B

(1)

(2)

(3)

(4)

4

9.12.4

75

D

(5)

(6)

(7)

(8)

(9)

(10)

(11)

(12)

115

75

25

5 ± 0.5

10 ± 0.5

30 + 0 30 + 0 30 – 1

2

4

6

100

140

100

30

5 ± 0.5

10 ± 0.5

30 + 0 30 + 0 30 – 1

2

4

6

125

175

125

35

5 ± 0.5

12 ± 0.5

30 + 0 38 + 0 30 – 1

3

6

6

G Dia

3

6

6

30 + 0 38 + 0 30 – 1 In case a continuous base plate is used, the thickness may be reduced to 3 mm. Hexagonal or round. More evenly placed screw holes may be provided, if so required by the purchaser. Specification for slotted countersunk head wood screws. 150

# ** $

E#

C Min

200

150

35

5 ± 0.5

12 ± 0.5

377

No. in Each Lug

Screw Holes** No. in a Size Designation of plate when Counter-sunk Head a continuous Wood Screws (see $ Plate is used IS : 6760-1972 )

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

FLOOR DOOR STOPPER - CAST TYPE Sub Head : Wood Work and PVC Work Clause : 9.15.20 B 12.5

C

A

40 16

Spring

Rubber Piece 16

Cover Plate

45R

20 T1

5 Body or Housing 8 φ Pin

32

18

12.5

2

25

DIMENSION Thickness of Door Shutter

A

B

C

Casting T1

30

35.0 ± 0.5

140.0 ± 0.5

13

35

40.0 ± 0.5

140.0 ± 0.5

8

40

45.0 ± 0.5

150.0 ± 0.5

13

45

50.0 ± 0.5

150.0 ± 0.5

8

Screw Designation No.

4.5 + 0.3 -0 4.5 ± 0.3 -0 4.5 + 0.3 -0 4.5 + 0.3 -0

No. of Holes for T1

9

4

9

4

9

4

9

4

Drawing not to Scale All dimensions are in mm

Fig. 9.13 : Floor Door Stopper – Cast Type

WINDOW STAY Sub Head : Wood Work and PVC Work Clause : 9.15.23

80 mm to Web

73

30

22 8 mm dia Pin 75

65

65

75

300 Locking Bracket

Drawing not to Scale All dimensions are in mm

Fig. 9.14 : Window Stay

CPWD SPECIFICATIONS 2009

378

18

HASP & STAPLES Sub Head : Wood Work and PVC Work Clause : 9.15.25

Install Thus T T for mild Steel Sheet T1 for Cast or Extruded Section of Brass

F

K

A ¼B

D

½B

G

¼B

R

B

E H

d D1

H for Mild Steel Sheet H' for Cast or Extruded Section or Brass

HASP (Mild Steel or Brass)

C Staple (Mild Steel) D+18

T1 D+1.5

R

K

T2

STAPLE (Brass or Aluminium) MILD STEEL

Size 90 115 150

A B 90±2 38±1.5 115±2 38±1.5 150±2 45±1.5

C 46±2 46±2 60±2

D 5.0± .10 5.0± .10 6.30± .10

E F 5.0± .5 35±1.5 5.0± .5 55±1.5 6.0± .5 65±1.5

G 28±1.5 28±1.5 33±.5

H 8±.5 8±.5 10±.5

J K 12±1 8±1 12±1 8±1 15±1 14±1

BRASS CAST OR EXTRUDED

Size 90 115 150

A 90±2 115±2 150±2

B 40±1.5 40±1.5 46±1.5

C 42±1.5 42±1.5 48±1.5

R 8±.5 8±.5 9±.5

ThickNess

D 5±.25 5±.25 6±.25

E 6±.5 6±.5 7±.5

F 35±1 45±1 65±1

G 28±.5 28±.5 32±.5

H 10±.5 10±.5 11±.5

K 8±1 11±1 14±1

R 6.5±.5 6.5±.5 7.5±.5

T1 2±.25 2±.25 3±.25

T2 3±.25 3±.25 4±.25

Thickness of Sheet

Dia of Hinge Pin d

Screw Holes No. on No. on Hasp Staple

T 2± .10 2± .10 2.24± .10

4± .10 4± .10 5± .10

3 3 4

Dia of Hinge Pin d

Dia of Butt D1

No. on Hasp

3.15±.10 3.15±.10 4±.10

6±.2 6±.2 8±.2

3 3 4

4 4 4

Screw Designation No. 8 8 10

Screw Holes No. on Screw Staple Designation No. 4 4 4

5 8 0

Drawing not to Scale All dimensions are in mm

Fig. 9.15 : Hasp & Staples 379

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

LVL SHUTTER Sub Head : Wood Work and PVC Work Clause : 9.16.6

Top Rail

1/3 t

100

Stile 2/3t

12 mm thick Rubber Wood Lipping Alround 100 PANEL Center Line of Lock Rail

100

100 mm Long Hinges

Beading for fixing Panel

Lock Rail

t

Fig. 9.16A : Single Tenon Joint

150

25 mm 65 mm

PANEL 850

200 mm

Beading for Fixing Panel

20 mm 65 mm

BOTTOM RAIL

200

25 mm

All Dimension are in mm

Fig. 9.16B : Double Tenon Joint

Fig. 9.16 : Typical Illustratino of Panelled LVL Door Shutter 0 to 10 mm

0 to 10 mm 1/3 1/2 1/3 1/3

A - Splayed Type

1/2 B - Square Type

Fig. 9.16D : Meeting of Stiles for Double Leaved Door Shutters Fig. 9.16C : Common Methods of Joining Panel with Stiles and Rails with/ without Beading

Fig. 9.16 : LVL Shutter

CPWD SPECIFICATIONS 2009

380

PARTITIONS Sub Head : Wood Work and PVC Work Clause : 9.17.2

Bo a

Fillet

r d fo

r Pa r titio n

Ceiling Channel s

Board Fillet Metal Stud at 610 mm Centres

Stud at 610 mm c/c

Calcium Silicate Board

Skirting

Skirting Floor Channel

ELEVATION Floor and Ceiling Channel ISOMETRIC VIEW

WALL AND END DETAIL

610

CORNER DETAIL

T-JUNCTION PLAN

DETAILS Board Board Fillets Floor/Ceiling Channel Stud Bracing Member Screws (C/S head)

8 / 10 / 12 mm Thick 60 / 100 mm 50 x 32 x 32 x 0.55 mm 48 x 50 x 48 x 0.55 mm 45 x 15 x 15 x 0.9 mm 25 & 35 mm long, self drilling with under head cutter

One layer board on each side of studs On each side of all studs and channels Top and bottom perimeter of the partition Vertically at 610 mm c/c At horizontal board joint on both side 12 mm from the edge & 40 mm from the corner of the board at 200 mm c/c

Fig. 9.17 : Partitions 381

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

UPVC DOOR FRAME Sub Head : Wood Work and PVC Work Clause : 9.18.1

40/50 mm

48/42 mm

SECTION A ELEVATION

21

16

150

Tie Rod

A

Cross Sectional View

MS Tube 19 X 19 mm

A

M S Tube 19 x 19 mm x 1mm thick

CROSS SECTION VIEW

Fig. 9.18 : UPVC Door Frame CPWD SPECIFICATIONS 2009

382

24 MM THICK PVC DOOR SHUTTERS

20

Sub Head : Wood Work and PVC Work Clause : 9.19.1

B

D

628

F

Section-A 59.0 H

24.0

A

A

Section-B

Steel Tube 20 x 20 Section-H

E

24 100.0

C

Section-C

43

17

100

17

G

255

220 Section-D

20

Section-E

16

17

100

150

Elevation

100 21

Cross Section View

21

H

20

16 Section-F Section-G

Fig. 9.19 : 24 mm Thick PVC Door Shutters

383

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

30 MM THICK PVC DOOR SHUTTERS

20

Sub Head : Wood Work and PVC Work Clause : 9.19.2

620 A D 30

D

60 B A

A

30

A

C F

100 C

F

18 18

130 mm

H

22

E

220 mm 25

D

Steel Tube

ELEVATION

16

250 150 E

Fig. 9.20 : 30 mm Thick PVC Door Shutters

CPWD SPECIFICATIONS 2009

384

30

16

21

CROSS SECTION VIEW

22

21

B H

F

PVC DOOR FRAME Sub Head : Wood Work and PVC Work Clause : 9.20.1 50 mm 5 mm 5 mm

C 150mm Long 'L' Shape Brakcet 15 mm x 15 mm sq. Tube 19 Gauge inserted into 19 x 19 mm M.S. Square Tube of 19 Guage

47 mm

Top Rail

15 mm

EDPM Rubber Gasket

Solid PVC Choukhat

5 mm

19 mm x 19 mm M.S. Square Tube

40 mm Lock Rail (Upper) (Detail at 'H')

75 mm Long M.S. Screws fixed with PVC Fasteners for Fixing Frame to Wall

Panel

75 mm Detail at 'F' PVC 'C' Channel

ELEVATION (Scale - 1 : 25)

25 mm

100 mm

100 mm

DETAIL AT 'D' (Scale - 1:3)

B

A

30 mm 25 mm

Bottom Rail

15 mm

Lock Rail (Lower) E

25 mm

Lock Rail

30 mm

D

100 mm

Hinge

Section View of Solid PVC Choukhat

25 mm

47

50 mm

25 mm

30 mm

5 mm PVC Panel

100 mm

Gap insert for Top

Detail at 'G' PVC 'C' Channel

PVC Beading

15 mm x 15 mm M.S. Square Tube

Gap insert below bottom Rail

15 mm

PVC Beading 5 mm PVC Panel

100 mm

Top Rail (Detail at -G) Gap insert below Top Rail

Detail at 'H' PVC Bottom Rail

Bottom Rail (Detail at - H) 15 mm x 15 mm M.S. Square Tube Gap insert for bottom Detail at 'E' (Scale - 1:3)

Detail at 'C' (Scale - 1 : 3)

19 mm M.S. 5 mm PVC Square Tube Beading 50 mm 75 mm

19 mm M.S. Solid PVC 5 mm PVC Square Tube Choukhat Beading 50 mm 75 mm

47 mm

Solid PVC Choukhat

40 mm

Hinge 5 mm PVC 'C' Channel (Detail at 'F') Detail at 'A' (Scale - 1 :3)

5 mm PVC Panel

40 mm

5 mm PVC 'C' Channel (Detail at 'F')

Detail at 'B' (Scale - 1 :3)

Fig. 9.21 : PVC Door Frame 385

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

30 mm THICK PANEL PVC DOOR SHUTTER Sub Head : Wood Work and PVC Work Clause : 9.21.1(a)

150 mm Long 'L' Shape Bracket

7 mm (5 mm + 2 mm PVC Beading)

75 mm 47 mm

B

Plain Solid PVC 19 mm x 19 mm M.S, Choukhat Square Tube 50 mm

Top Rail B

40 mm Hinge

Stiles

Beading

5 mm Taper Plain

5 mm PVC Sheet

PVC 'C' Channel (Sectional View 'AA')

19 mm M.S. Square Tube

C

50 mm

47 mm

Hinge

Tapper Lock Rail (Upper)

Lock Rail Gap insert for Top C

15 mm x 15 mm M.S. Square Tube Taper Plain Top Rail

75 mm Long Steel Screws Panel A

5 mm Both Side Prelam PVC Panel

A

7 mm (5+2) PVC Beading

7 mm (5mm + 2 mm) Lock Rail (Lower)

5 mm PVC Panel PVC Choukhat (Sectional View 'BB')

Bottom Rail

ELEVATION

15 mm M.S. Square Tube

Fig. 9.22 : 30 mm Thick Panel PVC Door Shutter

CPWD SPECIFICATIONS 2009

386

(Sectional View 'CC')

FRP DOOR FRAME Sub Head : Wood Work and PVC Work Clause : 9.22.0

750

Top Leg

z

z Left Leg

2100

Right Leg

Wooden Insert

MS Stay For Support

FRONT ELEVATION

FRONT ELEVATION SECTIONAL

PLAN

Wood

90

32

58

45

18 27

2 mm FRP Laminate

SECTION Z-Z (1:3)

Fig. 9.23 : FRP Door Frame

387

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

TYPICAL SKETCH OF FRP DOOR SHUTTERS Sub Head : Wood Work and PVC Work Clause : 9.23.1

Width of Shutter A

X Top Rail

90 B

Block for Fixing of Fitting

A

Panel B

B

Height of Shutter

90

Detail at X

90 Stile

Centre Line of Shutter

A

φ of Lock Rail Y Lock Rail

150

Detail at Y Recession for Fixing the Flaps of Hinges as specified by the buyer

Panel Size of Blocks A - 90 x 200 mm B - 90 x 150 mm C - 250 x 120 mm D - 150 x 150 mm

A 150 A

Stile

Bottom Rail

Panel

SECTION AT B-B

All dimensions in mm

Fig. 9.24A : Typical Sketch of FRP Door Shutters

CPWD SPECIFICATIONS 2009

388

850

Z Detail at Z SECTION AT A-A

SKETCH ILLUSTRATING DIMENSIONS OF SHUTTER Sub Head : Wood Work and PVC Work Clause : 9.23.1

Thickness of Door Frame - Rebate = 45 mm

M H - 95 mm = Height of Shutter

3 mm

M H - 10 mm = Overall Height of Door Frame

M H = Modular Height of Door Opening

5 mm Clearance

45 mm

Finished Floor Level 5 mm Clearance

40 mm

M w - 100 mm = Width of Shutter M w - 10 mm = Overall Width of Door Frame Mw = Modular Width of Door Opening

Structural Floor Level

Fig. 9.24B : Sketch Illustrating Dimensions of Shutter

389

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

SINGLE REBATE DOOR FRAME Sub Head : Wood Work and PVC Work Clause : 9.24.1

750

Fisher Screw

Door Frame (60 mm x 30 mm) 40 x 20 M.S. Pipe

2100

PVC Foam Profile Panel Door 3 mm Thick HPL Sheet Beading Profile Door Frame (60 mm x 30 mm)

DETAIL - X

60

30

PVC Foam Profile

22

FRONT ELEVATION

30

8

30

X Typical Door Frame Detail (60 mm x 30 mm)

100

230

INSIDE

OUTSIDE 690 750 PLAN

Drawing not to scale Al dimensions are in mm

Fig. 9.25 : Solid PVC Foam Profile Frame

CPWD SPECIFICATIONS 2009

390

DOOR SHUTTER DETAIL (28 MM THK - FABRICATION DETAIL) Sub Head : Wood Work and PVC Work Clause : 9.25.1 A 1

5

5 4

2

1 2

3 3 1 4

4

2

3

1

4 5 1 SECTION A-A ELEVATION 71

1

14

8

2

Details

12

SHUTTER FRAME PROFILE

1 BEDING

100

Shutter Frame

2

Beading

3

3 mm Thik. High Pressure Compact Laminate Sheet

4

40 x 20 x 19 g thk. M.S. Pipe

5

Telescopic Polymeric 'L' Corner

3

37

3MM THIK. HPL SHEET 17

100

37

5

SECTION-11

40

TELESCOPIC POLYMERIC 'L' CORNER 20

4

40 X 20 X 19 g THK. M.S. PIPE

Fig. 9.26 : Solid PVC Foam Shutter (28 mm Thick - Fabrication Detail) 391

SUB HEAD 9.0 : WOOD WORK AND P.V.C. WORK

F.R.P. CHAJJA Sub Head : Wood Work and PVC Work Clause : 9.26 12 mm Hole for Grouting Arrangement

2 mm M.S. Plate Sandwitched between F.R.P. Laminate

B

F.R.P. Chajja 4 mm Thick

50 mm Flange for Grouting inside the wall

A F.R.P. Chajja

Fig. 9.27 : F.R.P. Chajja

WALL PANELLING Sub Head : Wood Work and PVC Work Clause : 9.27

Perimeter Channel

Perimeter Channel Calcium Silicate Board Vertical M/F Ceiling Section

Calcium Silicate Board

Ceiling Section

Wall

Per

er C i met

h an n

Skirting

el

Perimeter Channel Fixed to the Soffit and floor

FRAME & BOARDING ARRANGEMENT

ELEVATION

Fig. 9.28 : Wall Panelling CPWD SPECIFICATIONS 2009

392

SUB HEAD : 10.0

STEEL WORK

CONTENTS Clause No.

Description List of Mandatory Tests

Page No. 397

List of Bureau of Indian Standards Codes

398

10.0

Definitions/Terminology

399

10.1

Materials

399

10.2

Steel Work in Single Section Fixed Independently with Connecting Plate

401

10.3

Steel Work in Built up Section (Riveted and Bolted)

402

10.4

Steel Work in Built up Section (Welded)

406

10.5

Collapsible Steel Gates

407

10.6

M.S. Sheet Sliding Shutter

408

10.7

M.S. Sheet Shutters

409

10.8

Rolling Shutters

410

10.9

Rolling Grills -Shutters

411

10.10

Steel Doors, Windows, Ventilators & Composite Units

412

10.11

T-Iron Doors, Windows & Ventilators Frames

417

10.12

Pressed Steel Door Frames

418

10.13

Tubular Hollow Section Trusses

420

10.14

Fan Clamps

421

10.15

M.S. Hollow Rectangular Door Frames (I-Type Section)

422

10.16

Factory Made Glazed Steel Doors, Windows and Ventilators

424

10.17

Steel Work for Staircases, Chequred Plate, Grating, Ladder, Railings, Bracket and Gate etc.

424

10.18

Steel Work for Hand Rails

424

395

SUB HEAD 10.0 : STEEL WORK

Appendix A

Mechanical Properties and Chemical Composition of Steel

425

Appendix B

Welding Process

428

Appendix C

Steel Tubes for Structural Purposes

429

Appendix D

Shapes, Weights and Designation of M S Rolled Steel Section

430

Fig. 10.1

Welds and Rivets

433

Fig. 10.2

Collapsible Steel Gate

434

Fig. 10.3

Typical M.S. Sheet Shutters

435

Fig. 10.4, 10.5 & 10.6

Doors, Windows and Ventilators

436

Fig. 10.7

Fixing Butt Hinges to T-Iron Frame with M.S. Flat Welded to Frame

439

Fig. 10.8

Pressed Steel Door & Window Frames

Fig. 10.9

Fan Clamps

CPWD SPECIFICATIONS 2009

440 442

396

LIST OF MANDATORY TESTS Material

Clause

1 2 Steel if 10.1.1 arranged by the contractor Steel 10.13 tubular pipes

Test

Field/ laboratory test

Test procedure

4 Laboratory

5 IS 1599

Laboratory (a) Tensile Test (b) Bend Test (c) Flattening Test

IS 1608

3 (a) Tensile strength (b) Bend test

397

IS 2329

Min. quantity of Frequency material for of testing carrying out the test 6 7 20 tonne Every 20 tonne or part thereof. Every 8 tonne or Every 8 part thereof tonne or part thereof

IS 2328

SUB HEAD 10.0 : STEEL WORK

LIST OF BUREAU OF INDIAN STANDARDS CODES Sl. No. 1 2 3 4 5 6 7.

Code No. IS 63 IS 198 IS 228 IS 277 IS 800 IS 806 IS 808

8. 9. 10

IS 812 IS 813 IS 814

11

IS 816

12 13

IS 817 IS 818

14 15 16 17

IS 822 IS 823 IS 1038 IS 1081

18 19 20

IS 1148 IS 1161 IS 1182

21 22

IS 1200- (Pt. VIII) IS 1363 Part I

23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

IS 1363 Part II IS 1363 Part-III IS 1367 IS 1599 IS 1608 IS 1821 IS 1852 IS 1894 IS 1977 IS 2062 IS 2074 IS 4351 IS 4454 (Part I) IS 4711 IS 4736 IS 4923 IS 6248 IS 7452

CPWD SPECIFICATIONS 2009

Subject Whiting for paints and putty Varnish gold size Structural steel (Standard quality) Specification for galvanized steel sheets (Plain and corrugated) Code of practice for use of structural steel in general in steel construction Code of practice for use of steel Tubes in general building construction Dimensions for Hot rolled steel beams, columns, channel and angle sections Glossary of terms relating to welding and cutting metals Scheme of symbols for welding Covered electrodes for manual metal arc welding of carbon and carbon manganese steel Code of practice for use of metal arc welding for general construction in mild steel Code of practice for training and testing of metal arc welders Code of practice for safety and healthy requirements in electric and gas welding and cutting operations Code of procedure for inspection of welds Manual for metal arc welding in mild steel Steel doors, windows and ventilators Code of practice for fixing and glazing of metal (Steel and aluminium) doors, windows and ventilators Hot rolled steel rivet bars (upto 40 mm diameters) for structural purposes Steel tubes for structural purposes Recommended practice for radiographic examination of fusion welded butt joints in steel plates Method of measurements of steel work and iron works Haxagon head bolts, screws, and nuts of product grade C (Hexagon Head bolt) Haxagon Head Bolts, screws and nuts of product Grade ‘C’ Haxagan Head Bolts, screws and Nuts of product grade ‘C’ Technical supply conditions for threaded steel fasteners Method for bend test Metallic materials – Tensile Testing at Ambient Temperature. Dimensions for clearance holes for bolts and screws Rolling and cutting tolerance for hot rolled steel products Method for tensile testing of steel tubes Structural steel (ordinary quality) Hot Rolled low, medium and high tensile structural steel Ready mixed paint, air drying redoxide zinc chrome priming Specification for steel door frames Steel wires for mechanical springs. Cold drawn unalloyed steel wire. Methods for sampling of steel pipes, tube and fittings. Hot – dip zinc coating on mild steel tubes Hollow Steel Sections for Structural Use - Specification Metal rolling shutters and rolling grills Specification for hot rolled steel sections for doors, windows and ventilators.

398

10.0 STEEL WORK 10.0 DEFINITIONS/ TERMINOLOGY Bead A single run of weld metal deposited on surface. Butt Weld A weld in which the weld metal lies substantially within the extension of the planes arc the surfaces on the parts joined. Crater A depression left in weld metal where the arc was broken or the flame was removed. End Crater A crater at the end of a weld or at the end of a joint. Fillet Weld A weld of approximately triangular cross-section joining two surfaces approximately at the right angles to each other in a lap joint, tee joint or corner joint. It is of two types: (1) Continuous (2) Intermittent. Fusion Welding Any welding process in which the weld is made between metals in a state of fusion without hammering or pressure. Non- fusion Welding A term applied to the deposition, by the Oxy-Acetylene process of filler metal on parent metal without fusion of the latter. Oxy-Acetylene Pressure Welding Pressure welding in which any Oxy-Acetylene flame is used to make the surface to be united plastic. No filler metal is used. Run The metal deposited during one passage of the electrode or blow pipe in the making of a joint. Throat thickness See Fig. 10.1. Weld A union between two pieces of metal at faces rendered plastic or liquid by heat or pressure, or both, Filler metal may be used to effect the union. 10.1 MATERIALS Micro-Alloying Elements Elements such as niobium, boron, vanadium and titanium added singly or in combination to obtain higher strength to weight ratio and better toughness, formability and weldability as compared to unalloyed steel of similar strength level.

399

SUB HEAD 10.0 : STEEL WORK

Weldability A metallic substance is considered to be weldable by a given process and for the given purpose, when metallic continuity to a stated degree can be obtained by welding using a suitable procedure, so that the joints comply with the requirements specified in regard to both their local properties and their influence on the construction of which they form a part. Controlled Rolling A hot rolling process in which the temperature of the steel and its reduction ratio are controlled, particularly during the final rolling passes, in order to achieve fine grain micro structure and optimum mechanical properties. Normalizing Rolling A hot rolling process in which the final rolling passes are carried out at a suitable higher temperature, followed by cooling in natural air to a temperature below the transformation temperature, in order to produce a structure, analogous to that obtained by a separate normalizing treatment of hot rolled product. 10.1.1 Steel 10.1.1.1 Supply of Material : General requirements relating to supply of structural steel shall conform to IS 8910. 10.1.1.2 Grades : There shall be nine grades of steel as given in Tables 10.1 and 10.2. While placing the order the steel should be designated by ‘Designation’ (See Table 10.1 and 10.2). 10.1.1.3 Manufacture : The processes used in the steel making and further hot rolling into steel plates, strips, sections, flats, bars, etc., are left to the discretion of the manufacturer/supplier. If required, secondary refining may follow steel making, as also normalizing rolling/controlled rolling during manufacturing of sections or as per the agreement between the purchaser and the manufacturer/ supplier. 10.1.1.4 Freedom from Defects 10.1.1.4.1 All finished materials shall be well and cleanly rolled to the dimensions, sections and masses specified. The finished material shall be reasonably free from surface flaws; laminations; rough/ jagged and imperfect edges and all other harmful defects. 10.1.1.4.2 Minor surface defects may be removed by the manufacturer/supplier by grinding provided the thickness is not reduced locally by more than 4 percent below the minimum specified thickness. Reduction in thickness by grinding greater than 4 percent but not exceeding 7 percent may be made subject to mutual agreement between the purchaser and manufacturer/supplier. 10.1.1.4.3 Subject to agreement with the purchaser, surface defects which cannot be dealt with as in 10.1.1.4.2 may be repaired by chipping or grinding followed by welding and inspection by a mutually agreed procedure such that : (a) After complete removal of the defects and before welding, the thickness of the item is not to be reduced by more than 20 percent at any place. (b) Welding is carried out by procedure APPROVED by competent authority with approved electrodes and the welding is ground smooth to the correct nominal thickness; and (c) Subsequent to the finish grinding, the item may be required to be normalized or otherwise heattreated at the purchaser’s discretion. 10.1.1.4.4 Welding as mentioned in 10.1.1.4.3 is not permissible for grade designation E 250 material. CPWD SPECIFICATIONS 2009

400

10.1.1.5 Chemical Composition : Ladle Analysis the ladle analysis of the steel, when carried out by the method specified in the relevant part of IS 228 or any other established instrumental /chemical method, shall be as given in Table 10.1. In case of dispute, the procedure given in IS 228 and its relevant parts shall be the referee method and where test methods are not specified shall be as agreed to between the purchaser and the manufacturer/supplier. 10.1.2 Rivets Rivets shall be made from rivet bars of mild steel as per IS 1148. 10.1.3 Bolts These are of two types namely turned and fitted bolts and black bolts. Turned & fitted bolts are turned to exact diameter in automatic lathe. For these bolts, whether reamed or drilled bolts, the same unit stresses are allowed as for rivets. In case of black bolts which are not finished to exact sizes, a lower working stress other than for turned bolts is adopted. They shall conform to IS 1367 – Technical supply conditions for threaded steel fasteners. 10.1.4 Electrodes The electrodes required for metal arc welding shall be covered electrodes and shall conform to IS 814. 10.2 STEEL WORK IN SINGLE SECTION FIXED INDEPENDENTLY WITH CONNECTING PLATE 10.2.0 The steel work in single section of R.S. joists, flats, Tees Angles fixed independently with or without connecting plate, is described in these clauses. 10.2.1 Fabrication The steel sections as specified shall be straightened and cut square to correct lengths and measured with a steel tape. The cut ends exposed to view shall be finished smooth. No two pieces shall be welded or otherwise jointed to make up the required length of member. All straightening and shaping to form, shall be done by pressure. Bending or cutting shall be carried out in such a manner as not to impair the strength of the metal. 10.2.2 Painting All surfaces which are to be painted, oiled or otherwise treated shall be dry and thoroughly cleaned to remove all loose scale and loose rust. Surfaces not in contact but inaccessible after shop assembly, shall receive the full specified protective treatment before assembly. This does not apply to the interior of sealed hollow sections. Part to be encased in concrete shall not be painted or oiled. A priming coat of approved steel primer such as Red Oxide/Zinc Chromate primer conforming to IS 2074 shall be applied before any member of steel structure are placed in position or taken out of workshop. 10.2.3 Erection Steel work shall be hoisted and placed in position carefully without any damage to itself and other building work and injury to workmen. Where necessary mechanical appliances such as lifting tackle winch etc. shall be used. The suitability and capacity of all plant and equipment used for erection shall be upto the satisfaction of the Engineer-in-charge. 10.2.4 Measurements The work as fixed in place shall be measured in running metres correct to a millimetre and weights calculated on the basis of standard tables correct to the nearest kilogram. The standard weight of steel sections shall conform to IS 808 with tolerance in sizes as per IS 1852. Tolerance in weight is given in Table 10.3. Steel sections shall be acceptable within tolerance limits. Payment for steel sections shall be made as per actual weight within tolerances. Sections having weight on higher side than permissible 401

SUB HEAD 10.0 : STEEL WORK

tolerance, may be acceptable but payment shall be made on the basis of standard weight only. Steel sections having weight variations lower side than permissible variation shall not be acceptable. Unless otherwise specified, weight of cleats, brackets, packing pieces, bolts, nuts, washers, distance pieces, separaters, diaphgram gussets (taking overall square dimension) fish plates, etc. shall be added to the weight of respective items. In riveted work allowance is to be made for weight of rivet heads. Unless otherwise specified an addition of 2.5% of the weight of structure shall be made for shop and site rivet heads in riveted steel structures. No deduction shall be made for rivet/ or bolt holes (excluding holes for anchor or holding down bolts). Deduction in case of rivet or bolt hole shall however be made if its area exceeds 0.02 sqm. The weight of steel sheets, plates and strips shall be taken from relevant Indian standards based on 7.85 Kg/m2 for every millimetre sheet thickness. For rolled sections, steel rods and steel strips, weight given in relevant Indian Standards shall be used. 10.2.5 Rate Rate includes the cost of labour and materials required for all the operations described above. 10.3 STEEL WORK IN BUILT UP SECTIONS (RIVETED AND BOLTED) The steel work in built up section (Riveted and bolted) such as trusses, framed work etc. is specified in this clause. 10.3.1 Laying Out A figure of the steel structure to be fabricated shall be drawn on a level platform to full scale. This may be done in full or in parts, as shown on drawings or as directed by the Engineer-in-Charge. Steel tape shall be used for measurements. 10.3.2 Fabrication Fabrication shall generally be done as specified in IS 800. In major works or where so specified, shop drawings giving complete information for the fabrication of the component parts of the structure including the location, type, size, length and details or rivets, bolts or welds, shall be prepared in advance of the actual fabrication and approved by the Engineer-in-charge. The drawings shall indicate the shop and field rivets, bolts and welds. The steel members shall be distinctly marked or stenciled with paint with the identification marks as given in the shop drawings. Great accuracy shall be observed in the fabrication of various members, so that these can be assembled without being unduly packed, strained or forced into position and when built up, shall be true and free from twist, kinks, buckles or open joints. Wooden or metal sheet templates shall be made to correspond to each member, and position of rivet holes shall be marked accurately on them and holes drilled. The templates shall then be laid on the steel members, and holes for riveting and bolting marked on them. The ends of the steel members shall also be marked for cutting as per required dimensions. The base of steel columns and the positions of anchor bolts shall be carefully set out at the required location. 10.3.2.1 The steel section shall be straight or to be straightened or flattened by pressure unless required to be of curvilinear form and shall free from twists. These shall be cut square either by shearing or sawing to correct length and measured by steel tape. No tow pieces shall be welded or joined to make up for the required length of member. 10.3.2.2 Making Holes : Holes through more than one thickness of materials for members, such as compound stanchion and girder flanges shall, where possible, be drilled after the members are CPWD SPECIFICATIONS 2009

402

assembled and tightly clamped or bolted together. Punching may be permitted before assembly, provided the holes are punched 3mm less in diameter than the required size and reamed after assembly to the full diameter. The thickness of material punched shall be not greater than 16 mm. Rivet Holes The diameter for rivets and black bolts holes shall be taken as the nominal diameter of a rivet/ black bolts plus 1.5 mm for rivets/ bolts of nominal diameter less than or equal to 25 mm” and 2.0 mm for rivets of nominal diameter exceeding 25 mm, unless specified otherwise. Holes for turned and fitted bolts shall be drilled or reamed large by 0.2 to 8 mm depending upon the dia. of bolts. Holes shall have their axis perpendicular to the surface bored through. The drilling or reaming shall be free from burrs, and the holes shall be clean and accurate. Holes for rivets and bolts shall not be formed by gas cutting process. Holes for counter sunk bolts shall be made in such a manner that their heads sit flush with the surface after fixing. 10.3.2.3 Assembly : Before making holes in individual members, for fabrication and steel work intended to be riveted or bolted together shall be assembled and clamped properly and tightly so as to ensure close abutting, or lapping of the surfaces of the different members. All stiffeners shall be fixed (or placed) tightly both at top and bottom without being drawn or caulked. The abutting joints shall be cut or dressed true and straight, and fitted close together. Web plates of girders, which have no cover flange plates, shall have their ends flush with the tops of angles unless otherwise required. The web plate when spliced, shall have clearance of not more than 5mm. The erection clearance of cleated ends of members connecting steel to steel shall preferably be not greater than 1.5 mm. The erection clearance at the ends of beams without web cleats shall not be more than 3 mm at each end but where for practical reasons, greater clearance is necessary, seating designed suitably shall be provided. Column splices and butt joints of struts and compression members requiring contact for stress transmission shall be accurately, machined and close butted over the whole section. In column caps and bases, the ends of shafts together with the attached gussets, angles, channels etc. after riveting together shall be accurately machined so that the parts connected, butt against each other over the entire surfaces of contact. Connecting angles or channels shall be fabricated and placed in position with great accuracy so that they are not unduly reduced in thickness by machining. The ends of all bearing stiffeners shall be machined or grounded to fit tightly both at top and bottom. 10.3.2.4 Riveting : Rivets shall be used, where slip under load has to be avoided. Preliminaries before Rivetings:- Members to be riveted shall have all parts firmly placed and held together before and during riveting, and special care shall be taken in this respect for all single riveted connections. For multiple riveted connections, a service bolt shall be provided in every third or fourth hole. Process of Riveting The riveting shall be carried out by using machines of the steady pressure type. However, where such facilities are not available hand riveting may be permitted by the Engineer-in-charge. The rivets shall be heated red hot, care being taken to control the temperature of heating so as not to burn the steel. Rivets of diameter less than10mm may be driven cold. Rivets shall be finished neat with heads full and of equal size. The heads shall be central on shanks and shall grip the assembled members firmly. 403

SUB HEAD 10.0 : STEEL WORK

All loose, burnt, or badly formed rivets with eccentric or deficient heads shall be cut out and replaced. In cutting out rivets, care shall be taken so as not to injure the assembled members. Caulking and recapping shall not be permitted. For testing rivets, a hammer weighing approx. 0.25 kg shall be used and both heads of the rivet (Specially the machine head) shall be tapped. When so tested, the rivets shall not give a hollow sound and a jar where so specified, other tests shall be carried out to ensure the soundness of rivets. All rivets heads shall be painted with approved steel primer paint within a week of their fixing. 10.3.2.5 Bolting : The nominal length of the bolt shall be the distance from the underside of the head to the further end of the shank. The nominal diameter of the bolt shall be the diameter at the shank above the screwed threads. Bolts, nuts and washers shall be thoroughly cleaned and dipped in double boiled linseed oil, before use. All bolts heads and nuts shall be hexagonal unless specified otherwise. The screwed threads shall conform to IS 1363 and the threaded surface shall not be tapered. The bolts shall be of such length as to project at least two clear threads beyond the nuts when fixed in position, and these shall fit in the holes without any shake. The nuts shall fit in the threaded ends of bolts properly. Where necessary, washers shall be tapered or otherwise suitably shaped to give the heads and nuts of bolts a satisfactory bearing. The threaded portion of each bolt shall project through the nut at least two thread. In all cases where the full bearing area of the bolt is to be developed, the bolt shall be provided with a washer of sufficient thickness under the nuts to avoid any threaded portion of the bolt being within the thickness of the parts bolted together. Where there is a risk of the nuts being removed or becoming loose due to vibrations or reversal of stresses, these shall be secured from slackening by the use of lock nut, spring washers as directed by the Engineer-in-charge. 10.3.3 Erection 10.3.3.0 Steel members shall be hoisted and erected in position carefully, without any damage to itself, other structures and equipment and injury to workmen. The method of hoisting and erection proposed to be adopted by the contractor shall be got approved from the Engineer-in-charge in advance. The contractor however shall be fully responsible for the work being carried out in a safe and proper manner without unduly stressing the various members and proper equipment such as derricks, lifting tackles, winches, ropes etc. shall be used. 10.3.3.1 The work of erection may be done in suitable units as may be directed by the Engineer-incharge. Fabricated members shall be lifted at such points so as to avoid deformation or excessive stress in members. The structure or part of it placed in position shall be secured against over-turning or collapse by suitable means. During execution, the steel members shall be securely bolted or otherwise fastened when necessary temporarily braced to provide for all loads including those due to erection equipments and its operation to be carried safely by structure during erection. The steel members shall be placed in proper position as per approved drawing, final riveting or permanent bolting shall be done only after proper alignment has been checked and confirmed. 10.3.3.2 Trusses shall be lifted only at nodes. The trusses above 10 m in span shall not be lifted by slinging at two mid points of rafters, which shall be temporary braced by a wooden member of a suitable section. After the trusses are placed in position, purlins and wind bracings shall be fixed as soon as possible.

CPWD SPECIFICATIONS 2009

404

The end of the truss which faces the prevailing winds shall be fixed with holding down bolts, and the other end kept free to move. In case of trusses of spans upto 10m the free end of the truss shall be laid on lead sheet or steel plate as per design, and the holes for holding down bolts shall be made in the form of oblong slots so as to permit the free movements of the truss end. For larger spans the truss shall be provided with proper bearing as per design. 10.3.3.3 Columns and stanchions shall be erected truly vertical with the necessary cross bracing etc. and the base shall be properly fixed with the foundation concrete by means of anchor bolts etc. as per drawing. 10.3.3.4 Anchor bolts to be placed in the concrete foundation should be held in position with a wooden template. At the time of concreting anchor bolt locations shall be provided with suitable timber mould or pipe sleeve to allow for adjustment which shall be removed after initial setting of concrete. The spaces left around anchor bolts shall be linked to a stopping channel in the concrete leading to the side of the pedestal and on the underside of the base plate to allow the spaces being grouted up after the base plate is fixed in the position along with the column footing. Grouting shall be of cement mortar 1:3 (1 cement: 3 coarse sand) or as specified. 10.3.3.5 Bedding of Column, Stanchions etc.:- Bedding shall not be carried out until the steel work has been finally levelled, plumbed and connected together. The stanchion shall be supported on steel wedges and adjusted to make the column plumb. For multistoreyed buildings, the bedding shall not be done until sufficient number of bottom lengths of stanchions have been properly lined, levelled and plumbed and sufficient floor beams are fixed in position. The base plates shall be wedged clear of the bases by M.S. wedges and adjusted where necessary to plumb the columns. The gaps under the base plate may be made upto 25 mm which shall be pressure grouted with cement grouts. With small columns, if permitted by the Engineer-in-charge, the column base shall be floated on a thick cement grout on the concrete pedestal. The anchor bolt holes in the base plate may be made about 10 to 15 mm larger than the bolts. In such cases suitable washers shall be provided. 10.3.4 Painting Before the members of the steel structure are placed in position or taken out of the workshop these shall be painted as specified in 10.2.2. 10.3.5 Measurements The work as fixed in position shall be measured in running metres correct to a millimeter and their weight calculated on the basis of standard tables correct to the nearest kilogram. The standard weight of steel sections shall conform to IS 808 with tolerance in sizes as per IS 1852. Tolerenace in weight is given in Table 10.3. Steel sections shall be acceptable within tolerance limits. Payment for steel sections shall be made as per actual weight within tolerances. Sections having weight on higher side than permissible tolerance, may be acceptable but payment shall be made on the basis of standard weight only. Steel sections having weight variations lower than permissible variation shall not be acceptable. Unless otherwise specified. Weight of cleats, brackets, packing pieces, bolts nuts, washers, distance pieces, separators diaphragm gussets (taking overall square dimensions) fish plates etc. shall be added to the weight of respective items. No deductions shall be made for skew cuts. In riveted work, allowance is to be made for weight of rivet heads. Unless otherwise specified and addition of 2.5% of the weight of structure shall be made for shop and site rivet heads in riveted steel structures. No deduction shall be made for rivet/ or bolt holes (excluding holes for anchor or holding down bolts). Deduction in case of rivet or bolt hole shall, however, be made if its area exceeds 0.02 m2. 405

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The weight of steel sheet and strips shall be taken from relevant Indian Standards based on 7.85 kg/m2 for every millimeter sheet thickness. For rolled sections, steel rods and steel strips, weight given in relevant Indian Standards shall be used. 10.3.6 Rate The rate shall include the cost of all materials and labour involved in all the operation described above. 10.4 STEEL WORK IN BUILT UP SECTION (WELDED) 10.4.0 The steel work in built up sections (welded) such as in trusses, form work etc. is specified in this clause. 10.4.1 Laying out It shall be as specified in 10.3.1. 10.4.2 Fabrication 10.4.2.1 Straightening, shaping to form, cutting and assembling, shall be as per 10.3.2 as far as applicable, except that the words “riveted or bolted” shall be read as “welded” and holes shall only be used for the bolts used for temporary fastening as shown in drawings. 10.4.2.2 Welding : Welding shall generally be done by electric arc process as per IS 816 and IS 823. The electric arc method is usually adopted and is economical. Where electricity for public is not available generators shall be arranged by the contractor at his own cost unless otherwise specified. Gas welding shall only by resorted to using oxyacetylene flame with specific approval of the Engineer-in-charge. Gas welding shall not be permitted for structural steel work Gas welding required heating of the members to be welded along with the welding rod and is likely to create temperature stresses in the welded members. Precautions shall therefore be taken to avoid distortion of the members due to these temperature stresses. The work shall be done as shown in the shop drawings which should clearly indicate various details of the joint to be welded, type of welds, shop and site welds as well as the types of electrodes to be used. Symbol for welding on plans and shops drawings shall be according to IS 813. As far as possible every efforts shall be made to limit the welding that must be done after the structure is erected so as to avoid the improper welding that is likely to be done due to heights and difficult positions on scaffolding etc. apart from the aspect of economy. The maximum dia of electrodes for welding work shall be as per IS 814. Joint surfaces which are to be welded together shall be free from loose mill scale, rust, paint, grease or other foreign matter, which adversely affect the quality of weld and workmanship. 10.4.2.3 Precautions : All operation connected with welding and cutting equipment shall conform to the safety requirements given in IS 818 for safety requirements and Health provision in Electric and gas welding and cutting operations. 10.4.2.4 Operation, Workmanship and process of Welding is described in Appendix B, 10.4.2.5 Inspection and testing of welds shall be as per IS 822. 10.4.2.6 Assembly : Before welding is commenced, the members to be welded shall first be brought together and firmly clamped or tack welded to be held in position. This temporary connection has to be strong enough to hold the parts accurately in place without any disturbance. Tack welds located in CPWD SPECIFICATIONS 2009

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places where final welds will be made later shall conform to the final weld in quality and shall be cleaned off slag before final weld is made. 10.4.2.7 Erection : The specification shall be as described in 10.3.3 except that while erecting a welded structure adequate means shall be employed for temporary fastening the members together and bracing the frame work until the joints are welded. Such means shall consists of applying of erection bolts, tack welding or other positive devices imparting sufficient strength and stiffness to resist all temporary loads and lateral forces including wind. Owing to the small number of bolts ordinarily employed for joints which are to be welded, the temporary support of heavy girders carrying columns shall be specially attended. Different members which shall be fillet welded, shall be brought into as close contact as possible. The gap due to faulty workmanship or incorrect fit if any shall not exceed. 1.5 mm if gap exceeds 1.5 mm or more occurs locally the size of fillet weld shall be increased at such position by an amount equal to the width of the gap. 10.4.2.8 Painting : Before the member of the steel structures are placed in position or taken out of the workshop these shall be painted as specified in para 10.2.2. 10.4.3 Measurements The mode of measurements shall be the same as specified in 10.2.4 except that weight of welding material shall not be added in the weight of members for payment and nothing extra shall be paid for making and filling holes for temporary fastening of members during erection before welding. 10.4.4 Rate The rate shall include the cost of all labour and materials involved in all the operations described above. 10.5 COLLAPSIBLE STEEL GATES 10.5.0 These shall be of approved manufacture and shall be fabricated from the mild steel sections. 10.5.1 The gates shall consist of double or single collapsible gate depending on the size of the opening. These shall consist of vertical double channels each 20 x 10 x 2 mm. at 10 cm. centre to centre braced with flat iron diagonals 20 x 5 mm and top and bottom rails of T- iron 40 x 40 x 6 mm @ 3.5 kg/m with 40 mm dia. ball bearings in every fourth double channel, unless otherwise specified. Wherever collapsible gate is not provided within the opening and fixed along the outer wall surface, T- iron at the top may be replaced by flat iron 40 x 10 mm. The collapsible gate shall be provided with necessary bolts and nuts, locking arrangement, stoppers and handles. Any special fittings like spring, catches and locks, shall be so specified in the description of item where so required. The gate shall open and close smoothly and easily. 10.5.2 Fixing T- iron rails shall be fixed to the floor and to the Lintel at top by means of anchor bolts embedded in cement concrete of floor and lintel. The anchor bolts shall be placed approximately at 45 cm centres alternatively in the two flanges of the T- iron. The bottom runner (T- iron) shall be embedded in the floor and proper groove shall be formed along the runner for the purpose. The collapsible shutter shall be fixed at sides by fixing the end double channel with T-iron rails and also by hold- fasts bolted to the end double channel and fixed in masonry of the side walls on the other side. In case the collapsible shutter is not required to reach the lintel, beam or slab level, a Tee-section suitably designed may be fixed at the top, embedded in masonry and provided with necessary clamps and roller arrangement at the top. All the adjoining work damaged in fixing of gate shall be made good to match the existing work, without any extra cost. 407

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10.5.3 Painting All the members of the collapsible gate including T-iron shall be thoroughly cleaned off rust, scales, dust etc. and given a priming coat of approved steel primer conforming to IS 2074 before fixing them in position. 10.5.4 Measurements The height and breadth shall be measured correct to a cm. The height of the gate shall be measured as the length of the double channels and breadth from outside to outside of the end fixed double channels in open position, of the gate. The area shall be calculated in square metres, correct to two places of decimal. 10.5.5 Rate The rate shall include the cost of materials and labour involved in all the operations described above. 10.6 M.S. SHEET SLIDING SHUTTER 10.6.0 These shall be manufactured as per drawings and specification. These shall be fabricated from mild steel sheets. 10.6.1 The shutters shall be double or single leaf shutter as specified. The shutters shall be fabricated of specified size of M.S. angle iron frame diagonally braced with the same size of M.S. angle riveted / welded together with 3mm gusset plate at junction to form a rigid frame. M.S. sheet of 1 mm thickness or as specified shall be fixed to the frame with rivets/welds as approved by the Engineer-in-charge. These shall also be provided with top and bottom guide rails of specified size angles or T- irons and 25 mm diameter pulley or with 25 mm diameter ball bearing at the bottom and guide block with steel pulleys at the top. The shutters shall also be provided with locking arrangement, handles, stoppers, and holdfasts, other fittings as specified in the description of the item. The guide rails shall be sufficiently long and continued along the wall on both ends so that the sliding shutters can rest against the walls, giving full opening when so required. 10.6.2 Fixing The guide rails shall be fixed to the floor by means of anchor bolts embedded in the cement concrete floor. The steel section at the top shall be suitably supported from the walls. Two channel sections shall be suitable fixed vertically below the extreme clamps in the wall and floor to avoid the shutter from going out of the supports at top and bottom. A suitable clamping arrangement will be provided at either end of the opening to avoid the shutters from rolling back into the opening. All the adjoining work damaged in fixing shall be made good to match the existing work. 10.6.3 Painting All members of the sliding shutters including fittings shall be thoroughly cleaned of rust, scales, dust etc. and given a priming coat of approved steel primer i.e. Red oxide zinc chrome primer conforming to IS 2074 before fixing them in position. 10.6.4 Measurements The height and width shall be measured correct to a cm and its area for payment shall be calculated in square metres correct to two places of decimal. The height of the shutter shall be measured from outside to outside of the guide rail and width out side to out side of the shutter including the vertical position channels in sides, when shutter closed. 10.6.5 Rate The rate shall include the cost of materials and labour involved in all the operation described above. It also includes the cost of the full length of guide rails.

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10.7 M.S. SHEET SHUTTERS 10.7.0 These shall be manufactured as per drawing and specification. These shall be fabricated from mild steel sheets and angle iron. 10.7.1 The doors shall be provided as double leaf shutters unless otherwise specified . The shutters shall be fabricated with frame of M.S. angle 40 x 40 x 6 mm @ 3.5 kg/ metre and two diagonal braces of the same section as shown in Fig. 3 unless otherwise specified. The frame shall be riveted and/ or welded at the junctions. Wherever riveting shall be done 3.15 mm (10 G) thick gusset plate shall be provided at the junction. M.S. sheet of 1 mm thickness or as specified, shall be fixed to the frame with rivets or welds as approved by the Engineer-in-charge. Alternatively the diagonal bracing may be replaced by one horizontal and two cross flats 30 x 6 mm as shown in Fig. 10.3 unless otherwise specified. The outer frame shall be provided with cleats made of section 40 x 10 mm and bent in the shape of angle cleats with one arm 150 mm long and the other arm 50 mm long and fixed to the angle iron frame of the door with two 12 mm dia bolts and nuts. For doors upto 2.40 m height, two angles cleats per door shall be provided. The cleat shall have a vertical leg of 150 mm which shall be fixed with frame and horizontal leg of about 50 mm which shall be provided with a hole of 24 mm dia and fixed in the projected pin of the pin clamp. 10.7.2 Fittings and Fixtures The shutters shall be fixed to the wall masonry with four pin clamps (pintles) where the height of the shutter is upto 2.4 m. Each pin clamp shall consist of 50 x 6 mm flat iron 45 cm long bent and forked at one end and provided with 20 mm diameter M.S. pin on the other. The pin shall be firmly riveted or welded to the pin clamp, the other end of which shall be embedded in masonry by means of cement concrete block 40 x 23 x 20 cm of 1:3:6 mix (1 cement :3 coarse sand:6 graded stone aggregate 20 mm nominal size). It shall be so placed that bottom pin shall face upwards and “top pin downward”in order that the gate may not be removed by lifting over pins. One hook with eye 45 cm long of 10 mm diameter shall be provided for each shutter to keep it fixed in open position. The hook shall be fixed in wall masonry with wooden block and the eye shall be fixed on 6 mm thick M.S. plate as staple and fixed in the shutter frame with rivet or weld. A cement concrete block 15 x 10 x 20 cm in 1:2:4 (1 cement:2 coarse sand:4 grades stone aggregate of 20 mm nominal size) mix shall be embedded in the floor or at junction of two shutters so that door shutter open only on the outside and not on the inside. The shutters shall also be provided with locking arrangement and two handles of the shape and pattern as approved by the Engineer-in-charge. 10.7.3 Painting All the members of the door including angle iron shall be thoroughly cleaned off rust, scales, dust etc. and given a priming coat of approved steel primer i.e. Red Oxide/ Zinc chrome primer confirming to IS 2074 before fixing them in position. 10.7.4 Measurements The width and height of shutters shall be measured to the nearest cm. The area shall be calculated in square metre correct to two places of decimal. 409

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10.7.5 Rate The rate shall include the cost of materials and labour involved in all the operation described above. Nothing extra shall be paid for cement concrete block or wooden blocks nor anything deducted for these from the measurement of the masonry wall. 10.8 ROLLING SHUTTERS 10.8.1 Rolling shutters shall conform to IS 6248. These shall include necessary locking arrangement and handles etc. These shall be suitable for fixing in the position as specified i.e. outside or inside on or below lintel or between jambs of the opening. The door shall be either push and pull type or operated with mechanical device supplied by the firm. Shutters upto 10 sq. metre shall be of push and pull type and shutters with an area of over 10 sq. metre shall generally be provided with reduction gear operated by mechanical device with chain or handle, if bearings are specified for each of operation, these shall be paid for separately. 10.8.1.1 Shutter : The shutter be built up of inter locking lath section formed from cold rolled steel strips. The thickness of the sheets from which the lath sections have been rolled shall be not less than 0.90 mm for the shutters upto 3.5 m width. Shutters above 9 metres width should be divided in 2 parts with provision of one middle fixed or movable guide channel or supported from the back side to resist wind pressure. The lath section shall be rolled so as to have interlocking curls at both edges and a deep corrugation at the centre with a bridge depth of not less than 12 mm to provide sufficient curtain of stiffness for resisting manual pressures and normal wind pressure. Each lath section shall be continuous single piece without any welded joint. When interlocked, the lath sections shall have a distance of 75 mm rolling centers. Each alternate lath section shall be fitted with malleable cast iron or mild steel clips securely riveted at either ends, thus locking in the lath section at both ends preventing lateral movement of the individual lath sections. The clips shall be so designed as to fit the contour of the lath sections. 10.8.1.2 Spring : The spring shall be of coiled type. The spring shall be manufactured from high tensile spring steel wire or strips of adequate strength conforming to IS 4454- Part I . 10.8.1.3 Roller and Brackets : The suspension shaft of the roller shall be made of steel pipe conforming to heavy duty as per IS 1161. For shutter upto 6 metre width and height not exceeding 5 metre, steel pipes of 50 mm nominal bore shall be used. The shaft shall be supported on mild steel brackets of size 375 x 375 x 3.15 mm for shutters upto a clear height of 3.5 metre. The size of mild steel brackets shall be 500 x 500 x 10 mm for shutters of clear height above 3.5 m and upto 6.5 m. The suspension shaft clamped to the brackets shall be fitted with rotatable cast iron pulleys to which the shutter is attached. The pulleys and pipe shaft shall connected by means of pretensioned helical springs to counter balance the weight of the shutter and to keep the shutter in equilibrium in any partly open position. 10.8.1.4 When the width of the opening is greater than 3.5 mtr. The cast iron pulleys shall be interconnected with a cage formed out of mild steel flats of at least 32 x 6 mm and mild steel dummy rings made of similar flats to distribute the torque uniformly. Self aligning two row ball bearing with special cast iron casings shall be provided at the extreme pulley and caging rings shall have a minimum spacing of 15mm and at least 4 number flats running throughout length of roller shall be provided. 10.8.1.5 In case of shutters of large opening with mechanical device for opening the shutter the roller shall be fitted with a purion wheel at one end which in contact with a worm fitted to the bracket plate, caging and pulley with two ball bearing shall be provided. 10.8.1.6 Guide Channel : The width of guide channel shall be 25 mm the minimum depth of guide channels shall be as follows:

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Clear width of shutters Upto 3.5 m 3.5 m upto 8 m 8 m and above

Depth of guide channel 65 mm 75 mm 100 mm

10.8.1.7 The gap between the two legs of the guide channels shall be sufficient to allow the free movement of the shutter and at the same time close enough to prevent rattling of the shutter due to wind. 10.8.1.8 Each guide channel shall be provided with a minimum of three fixing cleats or supports for attachment to the wall or column by means of bolts or screws. The spacing of cleats shall not exceed 0.75 m. Alternatively, the guide channels may also be provided with suitable dowels, hooks or pins for embedding in the walls. 10.8.1.9 The guide channels shall be attached to the jambs, plumb and true either in the overlapping fashion or embedded in grooves, depending on the method of fixing. 10.8.1.10 Cover : Top cover shall be of mild steel sheets not less than 0.90 mm thick and stiffened with angle or flat stiffeners at top and bottom edges to retain shape. 10.8.1.11 Lock plates with sliding bolts, handles and anchoring rods shall be as per IS 6248. 10.8.2 Fixing The arrangement for fixing in different situations in the opening shall be as per IS 6248. 10.8.2.1 Brackets shall be fixed on the lintel or under the lintel as specified with rawl. Plugs and screws bolts etc. The shaft along with the spring shall then be fixed on the brackets. 10.8.2.2 The lath portion (shutter) shall be laid on ground and the side guide channels shall be bound with ropes etc. The shutter shall then be placed in position and top fixed with pipe shaft with bolts and nuts. The side guide channels and cover frames shall then be fixed to the walls through the plate welded to the guides. These plates and bracket shall be fixed by means of steel screws bolts, and rawl plugs concealed in plaster to make their location invisible. Fixing shall be done accurately in a workmen like manner that the operation of the shutter is easy and smooth. 10.8.3 Measurements Clear width and clear height of the opening for rolling shutter shall be measured correct to a mm. The clear distance between the two jambs of the opening shall be clear width and the clear distance between the sill and the soffit (bottom of lintel) of the opening shall be the clear height. The area shall be calculated in square metres correct to two places of decimal. 10.8.4 Rate The rate shall include the cost of materials and labour involved in all the operations described above including cost of top cover and spring except ball bearing and mechanical device of chain and crank operation, which shall be paid for separately. 10.9 ROLLING GRILLS – SHUTTERS 10.9.0 Rolling grill shutter is meant to provide visibility or ventilation or both, the degree of protection and safety is less as compared to a rolling shutter. The situations where a certain amount of ventilation combined with safety is required rolling shutter-cum-grill may be provided in which the rolling shutter may have a rolling grill portion either at the top or at the bottom or at both places. In addition, the rolling 411

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grill portion may also be provided in the middle of the shutter. The total height of the grill portion in all the segments of rolling shutter-cum-grill shall not exceed 1.0 m and the height of the grill portion in any individual segment shall not be more than 0.5 m. 10.9.1 Rolling grills shutters are similar in design, construction and operation to rolling shutters and all the provisions of Para 10.8 shall be applicable to rolling grills shuters except in respect of the shutter portion, and shall conform to IS 6248. 10.9.2 Shutters Rolling grill shutter and the rolling grill portion of the rolling shutter-cum-grill shall be fabricated with 8 mm diameter mild steel round bars. Straight bars and bars bent to the required profile are placed alternatively and held in position with 20 mm wide and 5 mm thick mild steel flat links. Straight bars shall be spaced not exceeding 150 mm centre to centre and the bars bent to required profile shall be placed symmetrically between two consecutive straight bars. Unless otherwise specified or directed by the Engineer-in-charge, bars placed alternatively with straight bars shall be bent to form a corrugated profile such that the pitch of the corrugation is 100 to 120 mm and the depth of corrugation is 80 to 100 mm. all the bent bars shall have uniform profile. Straight bar along with the adjoining bent bars on it both sides shall be held in position by passing the bars through holes in the links. Each link shall have three holes and the length of the links shall be such that the distance from the centre of the hole to the nearest edge of the flat is not less than the diameter of the hole. The corner of the links shall be rounded. All links shall be of uniform size and shape. The spacing of the links measured along the straight bar shall be the same as centre to centre distance between two consecutive crests/ troughs of the bars bent to the required profile. Each bar and link shall be continuous single piece without any joint. 10.9.3 Measurement & Rate The measurement and rate shall be as specified in 10.8.3 and 10.8.4 respectively. In case of Rolling Shutter-cum-Grill, where the area of the grill portion is half or less than half the area of opening, it shall be measured and paid as rolling shutter and where the area of grill portion is more than half the area of opening, it shall be measured and paid as rolling grill. 10.10 STEEL DOORS, WINDOWS, VENTILATORS AND COMPOSITE UNITS (Fig. 10.4) Hot rolled steel sections for fabrication of steel doors, windows, ventilators and fixed lights shall conform to IS 7452. Shapes weights and designations of hot rolled sections shall be as per IS 7452. Appendix ’D’ indicates the purpose or the situation where the sections are normally used. Tolerance in thickness of the sections shall be + 0.2 mm. The fabricated steel doors, windows, ventilators and composite units shall confirm to IS 1038 with up-to-date amendments and shall be IS marked (IS 1038). 10.10.1 The steel doors and windows shall be according to the specified sizes and design. The size of doors and windows shall be calculated, so as to allow 1.25 cm clearance on all the four sides of opening to allow for easy fitting of doors windows and ventilators into opening. The actual sizes of doors, windows and ventilators shall not vary by more than + 1.5 mm from those given in the drawing. 10.10.2 Fabrication 10.10.2.1.1 Frames : Both the fixed and openable frames shall be made of sections which have been cut to length and mitred. The corner of fixed and openable frames shall be welded to form a solid fused welded joint conforming the requirements given below. All frames shall be square and flat. The process of welding adopted shall be flush but welding or can be any other process as agreed to between the supplier and the purchaser which shall fulfil the requirements given in clause 6.1.1 of IS 1038, metal arc welding or any other suitable method. The section for glazing shall be tennoned and riveted into the frames and where they intersect the vertical tie shall be broached and horizontal tee threads through it, and the intersection closed by hydraulic pressure. CPWD SPECIFICATIONS 2009

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10.10.2.1.2 Requirements of Welded Joints (i) Visual Inspection Test: When two opposite corners of the frame are cut, paint removed and inspected, the joint shall conform to the following:(a) Welds should have been made all along the place of meeting the members and tack welding shall not be permitted. (b) Welds should have been properly grounded and (c) Complete cross section of the corner shall be checked up to see that the joint is completely solid and there are no cavities visible. (ii) Micro and Macro Examinations: From the two opposite corners obtained for visual test, the flanges of the sections shall be cut with the help of a saw. The cut surface of the remaining portions shall be polished, etched and examined. The polished and etched faces of the weld and the base metal shall be free from cracks and cavity and reasonably free from under cutting overlaps, gross porosity and entrapped slag. (iii) Fillet Weld Test: The fillet weld in the remaining portion of the joint shall be fractured by hammering. The fractured surfaces shall be free from slag inclusion porosity, crack penetration defects and fusion defects. 10.10.2.2 Doors : The hinges shall be of 50 mm projecting type, Non projecting type hinges may also be used, if approved by Engineer-in-Charge. The hinge pin shall be of electro-galvanized steel or aluminum alloy of suitable thickness and size. Door handles shall be approved by the Engineer-inCharge. A suitable latch lock for door openable both from inside and outside shall be provided. In the case of double doors, the first closing leaf shall be the left hand leaf locking at the door from the push side. The first closing shutter shall have a concealed steel bolt at top and bottom. The bolts shall be so constructed as not to work loose or drop by its own weight. Single and double leaf shutter door may be provided with a three way bolting device. Where the device is provided in the case of double leaf shutters, concealed brass or steel bolts shall not be provided. 10.10.2.3 Windows (a) For fixed windows, the frames shall be fabricated as per 10.10.2.1.1. (b) Side hung windows. For fixing steel hinges, slots shall be cut in the fixed frame and hinges inserted inside and welded to the frame at the back. The hinges shall be of projecting type with thickness not less than 3.15 mm and length not less than 65 mm and width not more than 25 mm. Non projecting type hinges may also be allowed if approved by the Engineer-in-Charge. The diameter of hinge pins shall not be less than 6 mm. The hinge pin and washer shall be of galvanized steel or aluminum alloy of suitable thickness. For fixing hinges to inside frame, the method described above may be adopted but the weld shall be cleaned, or the holes made in the inside frame and hinge riveted. The handle of side hung shutters shall be pressed brass, cast brass, aluminium or steel protected against rusting and shall be mounted on a steel plate. Thickness of handle shall not be less than 3 mm in case of steel or brass and 3.5 mm in case of aluminium. The handle plate shall be welded, screwed and/ or revitted to the opening frame in such a manner that it should be fixed before the shutter is glazed and should not be easily removable after glazing. The handle shall have a two point nose which shall engage with a brass or aluminium alloy striking plate on the fixed frame in a slightly opened position as well as closed position. The boss of handle shall incorporate a friction device to prevent the handle from dropping under its own weight and the assembly shall be so designed that the rotation of the handle may not cause it to unscrew from the pin. 413

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The height of the handle plate in each type of standards windows will be as specified, otherwise it shall be at a height of 3/8 of the height of shutter, from its bottom. The strike plate shall be so designed and fixed in such a position in relation to the handle that with the later bearing against its stop, there shall be adequately tight fit between the casement and outer frames. In case where no friction type hinges are provided, the windows shall be fitted with peg stays which shall be either of black oxidised steel, pressed or cast brass or as specified, 300 mm long or as specified with steel peg and locking brackets. The pegs stay shall have three holes to open the side hung casement in three different angles. The peg stay shall be of minimum thickness 2 mm in case of brass or aluminium and 1.25 mm in case of steel. Where specified friction hinges shall be provided. Side hung shutters fitted with friction hinges shall not be provided with a peg stay. If specified, side hung shutters may be fitted with an internal removable fly proof screen in a 1.25 mm thick sheet steel frame to the outer frame of the shutter by brass turn buckles at the jambs, and brass studs at the sill to allow the screen being readily removed. The windows with removable fly proof screen shall be fitted with a through – the screen level operator at the sill level to permit the operation of the shutter through an angle of 90° without having to remove the fly proof screen. The lever shall permit keeping the shutter open in minimum three different positions. 10.10.2.4 Ventilators (a) Top Hung Ventilators The steel butt hinges for top hung ventilators shall be riveted to the fixed frame or welded to it at the back after cutting a slot in it. Hinges to the opening frame shall be riveted or welded. Top hung ventilators shall be provided with a peg stay with three holes which when closed shall be held tightly by the locking bracket. The locking bracket shall either be fitted to the fixed frames or to the window. (b)

Centre Hung Ventilators Central hung ventilators shall be hung on two pairs of brass or aluminium cup pivots as specified, riveted to the inner and outer frames of ventilators to permit the ventilator shutter to swing to angle of approx 85°. The opening portion of the ventilators shall be so balanced that it remains open at any desired angle under normal weather conditions.

10.10.2.4.1 A black oxidised steel spring catch approved by the Engineer-in-Charge shall be fitted in the centre of the top of the centre hung ventilator, for the operation of ventilators. The spring catch shall be secured to the frame with M.S. screws and shall close into a mild steel or malleable iron catch plate riveted, screwed or welded to the outside of the outer window frame bar. 10.10.2.4.2 A black oxidised cord pulley wheel in galvanized mild steel brackets shall be fitted at sill of the centre hung window with mild steel screws or alternatively welded together with mild steel or malleable iron cord-eye riveted or welded to the bottom inner frame bar of the window in a position corresponding to that of pulley. Removable fly-proof screen may be provided as specified in 10.10.2.3 (b). This shall be fitted with a through – the screen operator to enable operating and keeping the shutter open in minimum three different positions. 10.10.2.5 Composite Units : Composite Units consist of a combination of two or more units of doors, windows and ventilators etc. as the case may be. The different units shall be coupled by using coupling sections K-11B or K-12B (Ref. Appendix D) as the case may be. Wherever the ventilators, windows and doors shall be coupled with a coupling sections, mastic cement shall be applied between the junction to make the joint water tight.

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10.10.3 Glazing 10.10.3.1 Specifications described in para 9.6.4.6 shall apply. The glass panes shall have square corners and straight edges. The glass panes shall be so cut that it fits slightly loose in the frames. In doors, windows and clerestory windows of bath, WC and lavatories frosted glass panes shall be used which shall weight not less than 10.00 kg/m2. 10.10.3.2 Glazing shall be provided on the outside of the frame unless otherwise specified. Putty of approved make conforming to IS 419 shall be used for fixing glass panes. Putty shall be applied between glass panes and glazing bars. Putty shall then be applied over the glass pane, which shall stop 2 to 3 mm from the sight line of the back rebate to enable the painting to be done upto the sight line to seal the edge of the putty to the glass. The oozed out putty shall be cleaned and from putty cut to straight line. Quantity of putty shall not be less than 185 gm/ metre of glass perimetre. Putty shall be painted within 2 to 3 weeks, after glazing is fixed to avoid its cracking. Note: Putty may be prepared by mixing one part of white lead with three parts of finely powdered chalk and then adding boiled linseed oil to the mixture to form a stiff paste and adding varnish to the paste at the rate of 1 litre of varnish to the 18 kg paste. 10.10.3.3 Four glazing clips may be provided per glass pane for a size larger than 30 cm x 60 cm for all types, where the glass panes size exceed 80 cm x 200 cm, 6 glazing clips shall be used. In case of doors, windows and ventilators without horizontal glazing bars, the glazing clips may be spaced according to the slots, in the vertical members provided the spacing does not exceed 30 cm otherwise the spacing shall be 30 cm. Note: Where large size glass panes are required to be used or where the door or window is located in heavily exposed situation, holes for glazing clips have to be drilled prior to fabrication and cannot be done at any later stages. Use of glazing clips shall be specified while placing the order. 10.10.3.4 Where specially stipulated, fixing of glass panes may be done with metal or wooden beading instead of mere putty. Where beading are proposed to be used, the manufacturers shall be intimated in advance to drill holes for hard screws. Usually beads shall be fixed with screws spaced not more than 10 cm from each corner and the intermediate not more than 20 cm apart. When glass panes are fixed with wooden or metal beading having mitred joints, a thin layer of putty shall be applied between glass panes and sash bars and also between glass panes and the beading. Size of M.S. beading shall be 10 x 10 mm box section manufactured from 1.6 mm thick sheet unless otherwise specified in the item. Where metal beading is specified, extra payment shall be made on this account. 10.10.4 Finishing All steel surfaces shall be thoroughly cleaned of rust, scale and dirt. Where so specified. The steel surface shall be treated for rust proofing by the hot dip, zinc spray or electro galvanizing process. A priming coat of approved steel primer i.e. red oxide/ zinc chromate perimer conforming to IS 2074 shall be given. The fabricated steel door, windows, ventilators and composite units shall be inspected in the factory and approved by the Engineer-in-charge before priming coat is applied. Final finishing coat shall be given to the doors, windows and ventilators after they are erected and fixed in final position. The rate shall be exclusive of final finishing coats but shall include the priming coat. 10.10.5 Fixing 10.10.5.1 Steel, doors and windows shall be so stacked as to keep them in true shape without damage. Doors, windows and ventilators shall be fixed as described below. 415

SUB HEAD 10.0 : STEEL WORK

10.10.5.2 Opening may be flush or rebated as shown in the drawing. The opening may have rendered finish or a “fair faced” finish (i.e. without rendering as in case of marble or stone facing). Where openings are flush and with a rendered finish a clearance of 1.25 cm shall be provided between the steel frame and opening (See Fig. 10.6). In case of external masonry finish “fair faced” and with rebated jambs, a minimum 1.25 cm clearance between frame and opening shall provided (See Fig. 10.6) opening in steel work shall be so designed that the outer flange of the door, windows, or ventilator frame section overlaps the steel surface by 10 mm (see Fig. 10.6) Note : The sizes of Indian Standard doors, windows and ventilators, are designed for modular opening 1.25 cm larger all round than the doors, windows etc. This gap of 1.25 cm is for the purpose of fixing of doors, windows etc. In masonry opening, the gap is filled up with mastic cement and plaster after the door or windows is fixed in position. In the case of steel or timber modular opening, extra steel or timber fillets will be necessary to cover this gap of 1.25 cm. 10.10.5.3 Fixing in Masonry Openings (a) Fixing with Lugs (i) Doors, windows and ventilators unit, shall not be “built in” as the work proceeds but opening shall be left out and frames fitted afterwards so that the minimum specified clearance between opening and unit frame is left alround. The size of the opening shall first be checked and cleared of obstruction, if any. The position of the unit and fixing holes shall be marked on the jamb. Necessary holes shall be made in the masonry and lugs not less than 10 cm long 15 x 3 mm size M.S flat fixed in cement concrete blocks 15 x 10 x 10 cm size of 1:3:6 mix (1 cement : 3 coarse sand:6 graded stone aggregate 20mm nominal size). The frames of units shall be set in the opening by using wooden wedges at the jamb, head and sill, (wedges shall preferably be placed near the points where a glazing bar meets the frames and be plumbed in position).

(b)

(ii)

After, the frame shall be fixed with the lugs with 20 mm long and 6.3 mm dia. G.I. counter sunk machine screws and nuts. In case of flush opening which are rendered smooth, wedges shall be removed and gap between unit and the jambs shall be filled with cement mortar (Fig. 10.6)

(iii)

In case of flush jamb with external “fair faced” finish the gap between the opening and frame shall be filled with mastic from inside till it oozed out on eternal face. The oozing mastic shall be cleaned and flush pointed. The internal gap shall be filled with mastic to about 1/3rd depth the rest with cement mortar (Fig. 10.6).

(iv)

In case of rebated jambs and jambs finished “fair faced” externally, the mastic shall be freely applied to the inside channel of frame, jamb and sill, so as to ensure a watertight joint. After the units is firmly fixed in position surplus mastic shall be cleaned and flush pointed, as shown in Fig. 10.6.

Fixing with Screws and Plugs: In R. C. C. work where lugs cannot be embedded due to reinforcement bars etc. rawl plugs or other approved metallic fasteners may be fixed in proper position and frame fixed to them with 60 mm galvanized cross recessed head wood screws of designation 10.

10.10.5.4 Fixing in Wood Work Opening : Opening in wood work are normally rebated and approved mastic or rubber linings shall be applied to jambs, sill and channel before fixing in position, the frame shall be set in opening using wooden wedges as specified in 10.10.5.3 and fixed to the opening with 60 mm galvanized wood screws of designation 10. Extra timber fillets of hard wood to match the adjoining work shall also be provided around the frame to close the extra gap between opening and frame (Fig. 10.6). CPWD SPECIFICATIONS 2009

416

10.10.5.5 Fixing in Steel Work Opening : Before placing the unit frame in position approved mastic shall be applied as specified in 10.10.5.3 (a) (iv) and a mild steel or hard wood fillet shall be provided around the frame to close the extra gap between opening and frame. The unit shall then be fixed to the opening with fixing clips or with nuts and bolts as shown in the drawings or as directed by the Engineer-in-Charge (Fig. 10.6) 10.10.5.6 Fixing of Composite Units : The fixing procedure for composite units shall generally be as described under 10.10.5.1 to 10.10.5.5 except that: Where large units shall be formed by coupling individual units together (with coupling sections), the mullions and transom shall be bedded in mastic to ensure water tightness. Mastic shall be applied liberally to the channels of the outside frame section before assembly and after coupling. All oozing out mastic shall be cut out neatly. 10.10.6 Precautions Care shall be taken that steel doors and windows etc. are not deformed/ damaged during subsequent constructions. Particular care shall be taken that scaffolding do not rest on the steel door window frames or glazing bars. All fittings and hinges (projecting hinges) shall be protected, preferably with alkathene sheets so that these may not be damaged during execution of work. 10.10.7 Measurement The weight of finished section door/windows of different sizes, inclusive of all fixed /welded fittings i.e. hinges pivots, lugs, brackets striking plates etc,. shall be worked out before fixing of windows (exclusive of weight of glass panes, glazing clips, putty etc.). Sectional weight of steel members only shall be measured without weight of glass panes etc. Any loose fittings such as casement stays/fastners etc. shall be enumerated and paid for separately. 10.10.8 Rate Rate shall include the cost of materials and labour involved in all the operations described above excluding two coats of painting but including cost of glazing and priming including the cost of projecting hinges in case of side hung doors/windows, plain hinges in case of top/ bottom hung windows / ventilators and pivots for centre hung windows/ ventilators. Metal beading and other fittings such as peg stay and casement window fasteners etc. shall be enumerated and paid for separately. 10.11 T-IRON DOORS, WINDOWS AND VENTILATORS FRAMES. 10.11.0 T-iron doors, windows and ventilators frames shall be manufactured from uniform mild steel Tee section. The steel shall be of the grade as provided in 10.1.1 The frames shall be got fabricated in approved workshop as approved by the Chief Engineer. 10.11.1 The sizes of doors, windows and ventilator frames shall be as per drawing or as decided by the Engineer-in-Charge. MS tie bar of 10 mm dia shall be welded at bottom of the frame. The size of doors, window and ventilators shall be calculated so as to allow 12.5 mm clearance on all sides to allow an easy fittings in opening. The actual size of doors, windows and ventilator shall not vary by more than + 2 mm than those shown in the drawings. The size of T section used for manufacture of doors, windows and ventilators shall not be less than those specified in IS 1038 (see Fig. 10.5) unless otherwise directed by the Engineer-in-charge. 10.11.2 Fabrications The frame shall be constructed in section which has been cut to length and mitred. The corners of the frames shall be butt welded to form a true and right angle. All frames shall be square and flat meeting the requirements stated under para 10.10.2.1.1. 417

SUB HEAD 10.0 : STEEL WORK

The T Sections shall be mitre joined and continuously butt welded all along. The requirement of welded joints shall be as specified under para 10.10.2.1.2. 10.11.3 Fittings Requisite number of holes shall be made in the frame for fixing of fitting. Detailed arrangement of fixing fittings shall be as shown in Fig. 10.7. All fitting shall be fillet welded to T iron frame all along the periphery of contact. Butt hinges shall be fixed to the frame as below: (i) MS flat of size 100 mm x 25 mm x 6 mm will be welded with fillet weld all along the periphery of contact on the rear side of the web of T iron to receive the hinges. Requisite number of holes shall be made in T iron frame and MS flat for fixing of hinges with counter sunk steel screws as shown in Fig. 10.7. (ii) An alternate method of fixing butt hinges can be adopted by fillet welding the hinge to the T iron frame on three sided. No welding shall be done along the hinge pin to allow free movement of butt hinges as shown in Fig. 10.7. 10.11.4 Fixing Procedure Fixing procedure for T iron doors, windows and ventilator frames in masonry opening shall be as described in 10.10.5. Fixing arrangements of shutters to such frames is shown in Fig. 10.5. 10.11.5 Measurements T- iron door windows and ventilator frames shall be measured in running metre, along the centre line of the frame correct to a 1mm and weight calculated on the basis of standard tables. No deduction or extra payment shall be made for making holes and making arrangement for fixing fittings including packing wherever necessary. No deduction will be made for not providing tie bars in case of windows and ventilators. 10.11.6 Rate The rate includes cost of materials and labour involved in all the operation described above. It shall include the necessary butt hinges and screws for fixing the same with frame or as specified. But it does not include the cost of other door, window and ventilator fittings. 10.12 PRESSED STEEL DOOR FRAMES (Fig. 10.8) 10.12.1 Materials Steel door frames shall be manufactured from commercial mild steel sheet of specified thickness, conforming to IS 2062 and 4351. Steel door frames with or without fan light shall be made in the profiles indicated in Fig. 10.8 which may be manufactured to suit doors of either type opening inwards or outwards as directed by the Engineer-in-Charge. 10.12.2 Construction Each door frame shall consist of hinge jamb, lock jamb, head and if required angle threshold (see Fig. 10.8.) These shall be welded or rigidly fixed together by mechanical means. Where no angle threshold is required, temporary base tie shall be screwed to the feet of frames in order to form a rigid unit. Where so specified base ties shall be of pressed mild steel 1.25 mm thick adjustable to suit floor thickness of 35 or 40 mm and removable , or alternatively, threshold of mild steel angle of section 50 x 25 mm, minimum shall be provided for external doors frames. 10.12.3 Fabrication The pressed steel door frames shall be got fabricated in an approved workshop as approved by the Chief Engineer.

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10.12.3.1 Fixing Lugs (Fig. 10.8) : There shall be three adjustable lugs with split end tail to each jamb without fan light, and four for jamb with fan light. The head of the fixing lug shall be of one of the following lengths: (a) 98 mm long for use with profile A (b) 120 mm long for use with profile B (c) 160 mm long for use with profile C The head shall be made from flat steel strip 25 mm wide and not less than 1.60 mm thick The tail of the lugs shall be 200mm long and shall be made of steel strip not less than 40 mm wide and not less than 1 mm thick. 10.12.3.2 Hinges (Fig. 10.8) : 100 mm mild steel butt hinges shall be used. For door frames 80 cm wide and under, three hinges shall be rigidly fixed to one jamb and for door frames above 80 cm wide, four hinges shall rigidly fixed to one jamb, if it is single shutter, where the height of door shutter exceeds 2.15 metres, one additional hinge shall be provided for every 0.5 m or part thereof the additional height. In all cases the hinges shall be so fixed that the distance from the inside of the head rebate to the top of the upper hinge is 20 cm and the distance from the bottom of the door frame to the bottom of the bottom hinge is also kept about 200 mm. The middle hinges shall be at equal distances from lower and upper hinges or as agreed to between the purchaser and the supplier. Hinges shall be made of steel 2.5 mm thick with zinc coated removable pin of 6 mm diameter. The space between the two leaves of the hinge when closed shall be 3 mm and the leaf that is not welded to the frame shall have four counter sunk holes to take No. 10 cross recessed head wood screws. 10.12.3.3 Mortar Guards : Mortar guards of thickness of main frame sheet shall be provided in accordance to provisions of IS 4351 and as instructed by Engineer-in-charge shall be provided. These shall be welded to the frame at the head of the frame for double shutter doors to make provision for bolts. These shall also be provided to the frame behind the hinges, mortice locks and latches, slots, aldrop and sliding /tower bolts. 10.12.3.4 Lock – Strike Plate : There shall be an adjustable lock- strike plate of steel complete with mortar guard to make provision for locks or latches complying with the relevant Indian Standards. (IS 4351) Lock-strike plates shall be of galvanized mild steel and fixed at 95 cm from the head of the frame. 10.12.3.5 Shock Absorbers : For side hung door there shall not be less than three buffers or rubber or other suitable material inserted in holes in the rebate. one shall be located at the centre of the lock jamb and the other two shall be at 30 cm. from top and bottom of the frame. For double leaf shutter door, two buffers shall be provided. 10.12.4 Finishing The surface of door frame shall be thoroughly cleaned, free of rust, mill-scale dirt oil etc. either by mechanical means, for example sand or shot blasting or by chemical means such as picking. After pretreatment of the surface one coat of approved primer i.e. red oxide zinc chrome primer conforming to IS 2074. Two coats of paints as directed by the Engineer-in-charge shall be applied to the exposed surface. 10.12.5 Fixing Frames shall be fixed up right in plumb and plane. To avoid sag or bow in width during fixing or during construction phase, temporary struts across the width preventing sides bulging inwards may be provided. Wall shall be built solid on each side and grouted at each course to ensure solid contact with frame leaving no voids behind the frame. 419

SUB HEAD 10.0 : STEEL WORK

Three lugs shall be provided on each jamb with spacing not more than 75 cm. The temporary struts should not be removed till the masonry behind the frame is set. In case screwed base tie is provided, this should be left in position till the flooring is laid when it can be removed. After pretreatment of the surface, one coat of steel primer and two coats, of paint, as directed by Engineer-in-charge shall be applied to the exposed surface. 10.12.6 Measurements The length shall be measured in running metre correct to a cm along the centre line of the frames. 10.12.7 Rate The rate shall include the cost of labour and material involved in all the operation described above including one coat of approved steel primer but excluding two coats of paint. 10.13 TUBULAR / HOLLOW SECTION TRUSSES 10.13.1 Structural Steel Tube These shall be of: 1. Hot finished welded (HFW) type, or 2. Hot finished seamless (HFS) type, or 3. Electric resistance or induction butt welded (ERW), having carbon content less than 0.03 percent, yield stress of 21.5 kg/mm2 (YST 210) type. Conforming to the requirement of IS 1161. The steel tubes when analysed in accordance with the method specified in IS 228 shall show not more than 0.06 percent sulphur, and not more than 0.06 per cent phosphorous. Tubes shall be designated by their nominal bore. These shall be light, medium or heavy as specified depending upon the wall thickness. The standard size and weights of tubes are listed in Appendix C. Hollow sections shall be as per IS 4923. Tubes shall be clean finished and reasonably free from scale. They shall be free from cracks, surface flaws, laminations and other defects. The ends shall be cut clean and square with axis of tube, unless otherwise specified. 10.13.2 Minimum Thickness of Metals Wall thickness of tubes used for construction exposed to weather shall be not less than 4 mm and for construction not exposed to weather it shall be not less than 3.2 mm where structures are not readily accessible for maintenance, the minimum thickness shall be 5 mm. 10.13.3 Fabrication 10.13.3.1 The component parts of the structure shall be assembled in such a manner that they are neither twisted nor otherwise damaged and be so prepared that the specified cambers, if any, are, maintained. The tubular steel work shall be painted with one coat of approved steel primer after fabrication. All fabrication and welding is to be done in an approved workshop. The joint details shall be generally as per S.P-38 of B.I.S publication. 10.13.3.2 Straightening : All material before being assembled shall be straightened, if necessary, unless required to be of curvilinear form and shall be free from twist. 10.13.3.3 Bolting : Washers shall be specially shaped where necessary, or other means, used to give the nuts and the heads of bolts a satisfactory bearing. CPWD SPECIFICATIONS 2009

420

In all cases, where the full area of the bolts is to be developed, the threaded portion of the bolt shall not be within the thickness of the parts bolted together and washers of appropriate thickness shall be provided to allow the nuts to be completely tightened. 10.13.3.4 Welding : Where welding is adopted, it shall be as per IS 816. 10.13.3.5 Caps and Bases for Columns : The ends of all the tubes, for columns transmitting loads through the ends, should be true and square to the axis of the tubes and should be provided with a cap or base accurately fitted to the end of the tube and screwed, welded or shrunk on. The cap or base plate should be true and square to the axis of the column. 10.13.3.6 Sealing of Tubes : When the end of a tube is not automatically sealed by virtue of its connection be welding to another member the end shall be properly and completely sealed. Before sealing, the inside of the tubes should be dry and free from loose scale. 10.13.3.7 Flatened Ends : In tubular construction the ends of tubes may be flattened or otherwise formed to provide for welded. Riveted or bolted connections provide that the methods adopted for such flattening do not injure the material. The change of sections shall be gradual. 10.13.4 Hoisting and Erection Tubular trusses shall be hoisted and erected in position carefully, without damage to themselves, other structure, equipment and injury to workman. The method of hoisting and erection proposed to be adopted shall be got approved from the Engineer-in-charge. The contractor shall however be fully responsible, for the work being carried out in a safe and proper manner without unduly stressing the various members. Proper equipment such as derricks, lifting tackles, winches, ropes etc. shall be used. 10.13.5 Measurements The work as fixed in place shall be measured in running metres correct to a centimeter on their weights calculated on the basis of standard tables correct to the nearest kilogram unless otherwise specified. Weight of cleats, brackets, packing pieces bolts nuts, washers distance pieces separators diapharam gussests (taking overall square dimensions) fish plates, etc. shall be added to the weight of respective items unless otherwise specified. No deduction shall be made for skew cuts. 10.13.6 Rate The rate shall include the cost of labour and materials involved in all the operations described above including application of one coat of approved steel primer, i.e. red oxide zinc chrome primer conforming to IS 2074. 10.14 FAN CLAMPS (Fig. 10.9) 10.14.1 The fan clamps shall be of the following types: (a) Fan clamp to be fixed during the laying of R.C.C. slab, shall be of type I, as shown in (Fig. 10.9) This shall be made of 16 mm M.S. bar bent to shape with its ends hooked. The overall height of the clamps shall be made to suit the depth of slab. . (b) Fan clamps for beams shall be of type II as shown in (Fig. 10.9). It shall be similar to fan clamp, type I, except that its height shall be greater depending on the depth of the beam rib. (c) In case low ceiling heights, circular cast iron box for ceiling fan clamp shall be fixed during the laying of R.C.C. slab and shall be as shown in (Fig. 10.9). The size of cast iron box shall be 421

SUB HEAD 10.0 : STEEL WORK

140 mm internal dia with 73 mm height, the thickness of cast iron rim shall be 4.5 mm bottom and top lid shall be of 1.5 mm thick M.S. sheet, with its top surface hacked so as to ensure proper bonding with the concrete. The lids shall be screwed into the cast iron box by means of 3.3 mm dia round head screws one each at the corners. The box can be of M.S. sheet, the thickness of side walls can be reduced to 3 mm without effecting inner dia of the box. The fan clamp shall be made of 12mm dia M.S. bar bent to shape with its ends bent as per drawing. 10.14.2 Fixing Holes for inserting the fan clamps in the positions shown in the drawing or as instructed by the Engineer-in-charge shall be made in the shuttering after the latter has been fixed in position. After steel reinforcement is tied, fan clamps shall be fixed with their loops truly vertical and at the correct depth from the under-side of the slab or beam. The hooked arms and the loop shall be tied to the reinforcement, either directly or through cut pieces of M.S. bars with annealed steel wire 1.6 mm or 1.00 mm thick. The clamp shall neither be disturbed out of position during concreting nor shall they be bent out of shape when shuttering of slabs or beams is removed. The exposed portion of loops of the clamps shall be given two or more coats of paint, including priming coat, of approved steel primer as ordered by the Engineer-in-charge. 10.14.3 Measurements Clamps of type I and 3 shall be counted in numbers. Fan clamps type II, shall be counted and paid for under fan clamps type I, but they shall in addition be paid for their extra height as determined by the depth of the beam. 10.14.4 Rate The rate per fan clamps shall include the cost of labour and materials involved in all the operations described above. In the case of type I and 3 clamps, the rate shall apply irrespective of the thickness of the slabs. 10.15 M.S. HOLLOW RECTANGULAR DOOR FRAMES (l-TYPE SECTION) 10.15.1 Materials Steel door frames shall be manufactured from commercial mild steel sheet of 1.60 mm thickness, conforming to IS 2062 and 4351. Steel door frames shall be made in the profiles as per drawings and/or as directed by the Engineerin-charge. 10.15.2 Construction Each door frame shall consist of hinge jamb, lock jamb, head and if required angle threshold. These shall be welded or rigidly fixed together by mechanical means. Where no angle threshold is required, temporary base tie shall be screwed to the feet of frames in order to form a rigid unit. Where so specified base ties shall be pressed mild steel 1.60 mm thick adjustable to suit floor thickness of 35 or 40 mm and removable, or alternatively, threshold of mild steel angle of section 50 x 25 mm, minimum shall be provided for external doors frames. 10.15.3 Fabrication The M.S hollow rectangular steel door frames shall be got fabricated in an approved workshop as approved by the Chief Engineer. 10.15.3.1 Fixing Lugs : There shall be three adjustable lugs with split end tail to each jamb.

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The head of the fixing lug shall be 120 mm long and made up flat steel strip 25 mm wide and 1.60 mm thick. 10.15.3.2 Hinges 100 mm mild steel butt hinges shall be used. Floor door frames 80 cm wide and under, three hinges shall be rigidly fixed to one jamb and for frames of door above 80 cm wide, four higes shall be rigidly fixed to one jamb, if it is single shutter. Where the height of door shutter exceeds 2.15 metres, one additional hinge shall be provided for every 0.5 m or part thereof of the additional height. In all cases the hinges shall be so fixed that the distance from the inside of the head rebate to the top of the upper hinge is 20 cm and the distance from the bottom of the door frame to the bottom of the bottom hinge is also kept about 200 mm. The middle hinges shall be at equal distance from lower and upper hinges or as agreed to between the purchaser and the supplier. Hinges shall be made of steel 2.5 mm thick with zinc coated removable pin of 6 mm diameter. The space between the two leaves of the hinge when closed shall be 3 mm and the leaf that is not welded to the frame shall have four counter sunk holes to take Number-10 cross recessed head wood screws. 10.15.3.3 Aldrops, Sliding Bolts and Tower Bolts : Provisions shall be made for aldrops, sliding bolts and tower bolts in the frames as per the positions given by the purchaser. Necessary mortar guards/metallic or nylon bushes shall be provided inside the frames for aldrops, sliding bolts and tower bolts. 10.15.3.4 Lock Strike Plate : Provision shall be made to fix lock stricke plates of mortise locks or latches, complying with the relevant Indian Standards. A slot suitable for lock stricke plate shall be pierced into the rebate of the frame and necessary fixing arrangement and mortar guard from the inside of the frame shall be provided. 10.15.3.5 Shock Absorbers : For side-hung door there shall be not less than three buffers of rubber or other suitable material inserted in holes in the rebate and one shall be located at the centre of the lock jamb of frame and other two shall be 300 mm from top and bottom of the frame. For double leaf doors two buffers shall be provided. 10.15.4 Finishing The surface of door frame shall be thoroughly cleaned, free of rust, mill –scale dirt, oil etc. either by mechanical means, for example sand or shot blasting or by chemical means such as picking. After pretreatment of the surface one coat of approved primer i.e. red oxide zinc chrome primer conforming to IS 2074. Two coats of paints as directed by the Engineer-in-Charge shall be applied to the exposed surface. 10.15.5 Fixing Frames shall be fixed up right in plumb and plane. To avoid sag or bow in width during fixing or during construction phase, temporary struts across the width preventing sides bulging inwards may be provided. Wall shall be built solid on each side and grouted at each course to ensure solid contact with frame leaving no voids behind the frame. Three lugs shall be provided on each jamb with spacing not more than 75 cm the temporary struts should not be removed till the masonry behind the frame is set. In case screwed base tie is provided, this should be left in position till the flooring is laid when it can be removed. After pretreatment of the surface one coat of steel primer and two coats, of paint, as directed by Engineer-in-charge shall be applied to the exposed surface.

423

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10.15.6 Measurements The length shall be measured in running metre correct to a cm. along the centre line of the frames. 10.15.7 Rate The rate shall include the cost of labour and material involved in all the operation described above including one coat of approved steel primer but excluding two coats of paint. 10.16 FACTORY MADE GLAZED STEEL DOORS, WINDOWS AND VENTILATORS 10.16.0 Specifications for this item to be same as for standard steel glazed doors, windows and ventilators as mentioned in para 10.10, except that Doors, windows and ventilators to be manufactured in a workshop, approved by the Chief engineer. Also owner of the workshop shall have a valid ISI license for manufacture of doors, windows and ventilators. 10.17 STEEL WORK WELDED IN BUILT-UP SECTIONS USING STRUCTURAL STEEL (A) In Stringers, Treads, Landing etc. of Stair cases including use of Chequred Plate wherever required (B) In Grating, Frames, Guard Bar, Ladder, Railings, Brackete, Gates and similar work. 10.17.1 General specifications for these items to be same as for steel work welded in built-up sections as mentioned in para 10.4 except that steel used for fabrication of these items to be of type used for structural use/purposes. 10.17.2 Steel members used for fabricating these items to be designed structurally to withstanding the all loads to be carried out by the members during erection, fixing and functional use in designed life. Work to be executed as per structural drawings. 10.18 STEEL WORK WELDED IN BUILT-UP SECTIONS FOR HAND RAIL USING M.S. TUBULAR/ERW TUBULAR PIPES AND G.I. PIPES 10.18.1 General specifications to be same as for steel work welded in built-up section as mentioned in para 10.4. 10.18.2.1 Hot finished welded (HFW) Hot finished seamless (HFS) and electric resistance welded tube shall conform to IS 1161. 10.18.2.2 G.I. pipes used for Hand rail to be conforming to IS 1239-Part I for medium grade. GI pipes to be screwed and socketed type and of required nominal bore. 10.18.2.3 Galvanising of GI pipes shall conform to IS 4736. 10.18.2.4 All screwed tubes and socket of GI pipes shall have pipe threads conforming to the requirements of IS 554. 10.18.2.5 The fittings for GI pipes to be conforming to IS 1239 (Part-II). 10.8.3 Measurement of Hand Rail of M.S. Tubular/E.R.W Tubular Pipes The work as fixed in place shall be measured in running metres correct to a centimeter and their weights calculated on the basis of standard tables correct to the nearest kilogram or actual weight whichever is less unless otherwise specified.

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APPENDIX A MECHANICAL PROPERTIES AND CHEMICAL COMPOSITION OF STEEL TABLE 10.1 Chemical Composition (Clause 10.1.1) Grade Designation

Quality

1 E 165 (Fe 290) E 250 (Fe 410 W) E 250 (Fe 410 W) E 250 (Fe 410 W) E 300 (Fe 440) E 350 (Fe 490) E 410(Fe 540) E 450 (Fe 570 ) E 450 (Fe 590)

2 A B C D E

Ladle analysis, Percent, Max C 3 0.25 0.23 0.22 0.20 0.20 0.20 0.20 0.22 0.22

Mn. 4 1.25 1.50 1.50 1.50 1.30 1.50 1.60 1.60 1.80

S 5 0.045 0.045 0.045 0.040 0.045 0.045 0.045 0.045 0.045

P 6 0.045 0.045 0.045 0.040 0.045 0.045 0.045 0.045 0.045

Si 7 0.40 0.40 0.40 0.45 0.45 0.45 0.45 0.45

Carbon Equivalent (CE), Max

Method of Dexodiation1

8 0.42 0.41 0.39 0.40 0.42 0.44 0.46 0.48

9 Semi-killed or killed Semi-killed or killed Killed Killed Semi-killed or killed Semi-killed or killed Semi-killed or killed Semi killed or killed Semi killed or killed

Notes: Mn 1.

Carbon equivalent (CE) based on ladle analysis =

(Cr+Mo+ V) +

(Ni + Cu) +

C+6 5 15 When the steel is killed by aluminium alone, the total aluminium content shall not be less than 0.02 per cent. When the steel is killed by silicon alone, the silicon content shall not be less than 0.10 per cent. When the steel is silicon-aluminium killed, the silicon content shall not be less than 0.30 per cent and total aluminium content shall not be less than 0.01 per cent. 3. Microalloying element like Nb, V, Ti and B shall be added singly or in combination. Total microalloying element shall not be more than 0.25. 4. New grades designation system based on yield stress has been adopted, simultaneously old designations have also been given in parentheses. 5. Steel of qualities A, B and C are generally suitable for welding processes. The weldability increases from quality A to C. 6. Copper may be present between 0.20 to 0.35 per cent as mutually agreed to between the purchaser and the manufacturer. The copper bearing quality shall be designated with a suffix Cu, for example, E 250 Cu. In case of product analysis the copper content shall be between 0.17 and 0.38 per cent. 7. Nitrogen content of steel shall not exceed 0.012 per cent which shall be ensured by the manufacturer by occasional check analysis. For micro alloyed steel this is to be reduced to 0.009 per cent. 8. The steel, if required may be treated with rare earth element for better formability. 9. Lower limits for carbon equivalent and closer limits for other elements may be mutually agreed to between the purchaser and the manufacturer. 10. Incidental element-Elements not quoted in Table 1 shall not be intentionally added to steel without the agreement of the purchaser, other than for the purpose of finishing the heat. All reasonable precautions shall be taken to prevent the addition from scrap or other materials used in manufacture of such elements which affect the hardenability, mechanical properties and applicability. ---------------------------1. “To be supplied subject to the agreement between the purchaser and the manufacturer”. 2.

425

SUB HEAD 10.0 : STEEL WORK

TABLE 10.2 Mechanical Properties (Clause 10.1.1) Grade Designation

1 E 165 (Fe 290) E 250 (Fe 410 W) E 250 (Fe 410 W) E 250 (Fe 410 W) E 300 (Fe 440) E 350 (Fe 490) E 410 (Fe 540) E450 (Fe 570) E 450 (Fe 590)

1 2 3

Quality

Tensile strength Min. MPa

Yield stress, ReH Min. MPa

<20

2040

>40

4

5 165

6

Percentage elongation at Guage length Lo 5.65 √SO Min.

Internal Bend Diameter Min.)

Charpy V-Notch Impact Energy Min. J

At 20oC

9 -

at Room Temp. 10 -

-

< 25

>25

7 23

8 2t

2 -

3 290

11 -

A

410

250 240

230

23

3t

2t

B

410

250 240

230

23

2t

3t

27 (See Note 3 )

C

410

250 240

230

23

2t

3t

27 (See Note 3 )

-

440

300 290

280

22

2t

3t

50

30

-

490

350 330

320

22

2t

3t

50

25

-

540

410 390

380

20

2t

3t

50

25

D

570

450 430

420

20

2t

3t

45

20

E

590

450 430

420

20

2t

3t

45

20

1 MPa= 1MN/m2= 0.102 kgf/mm2=144.4 psi Temperature of Charpy impact values will be subject to mutual agreement. The more stringent requirements than those given above may be as agreed to between the purchaser and the manufacturer.

CPWD SPECIFICATIONS 2009

426

TABLE 10.3 (Clause 10.2.4 &10.3.5) Sl. No.

Steel Section

(i)

Beams and columns (RS joists)

(ii) (iii)

Channels Equal and unequal leg Angles (a) upto 3 mm thickness (b) Over 3 mm thickness Tee bars (a) Web thickness upto 3 mm (b) Web thickness above 3 mm Bulb angles Bars in straight length Upto and including 10 mm Over 10 mm and upto and including 16 mm Over 16 mm Bars in coils Flats Upto 3 mm thickness Over 3 mm thickness Plates Strips Consignment in straight length (i) upto 5 tons (ii) Above 5 tons Sheets

(iv)

(v) (vi)

(vii) (viii)

(ix) (x)

(xi)

Over in mm

1.25 mm 1.6

Tolerance in weight per meter percentage Plus Side Minus Side (a) Beams < 200 mm (-) 1 (+) 4 (b) > 200 mm 2.5 2.5 2.5 2.5

Standard weight as per IS IS 808

IS 808

5 5

5 3

IS 808

5 2.5 2.5

5 2.5 2.5

IS 1173

7 5

7 5

IS 1732

IS 1252

3 3 Weight tolerance is not applicable 5 5 5 10

5 3 2.5 10

7 5

7 5

IS 1730

IS 1730

1.25 mm

Tolerance on calculated weight (Percent) +9

1.60 4.00

+8 +7

Thickness Upto and including in mm

427

IS 1730 IS 1730

SUB HEAD 10.0 : STEEL WORK

APPENDIX B WELDING PROCESS (Clause 10.4.2.4) (a) The work shall be positioned for downward welding wherever possible. (b) Arc length voltage and amperage shall be suited to the thickness of material, type of groove and other circumstances of the work. The welding current and electrode sizes for different types of joints shall be as per IS 9595. (c) The sequence of welding shall be such as will avoid undue distortion and minimize residual shrinkage stresses. Recommendation of IS 9595 shall be followed. Process of Welding The electrode manipulation during welding shall be such as to ensure that: (1) The parent metal is in a fused stage when the filler metal makes contact with it. (2)

The weld metal does not overflow upon any unfused parent metal forming overlapping.

(3)

The parent metal is not under-cut along the weld toes.

(4)

The flowing metal floats, the slag, the oxides, and the gas bubbles to the surface behind the advancing pool. In case any of these requirements is unattainable by manipulation, the current shall be adjusted or the electrode size changed. Each time the arc is started the electrode shall be moved in such a way that the fusion of base metal at the starting point is assured. At the completion of a run the movement of electrode shall be slowed down to fill the arc crater. After every interruption of the arc except at completion of a run, the arc shall be restarted ahead of the previous deposit and then move back to fill the crater or such alternative technique shall be used as will ensure complete filling of the crater, or complete fusion between the new and old deposit and the base metal at the point of junction, and result in continuity of weld, Before welding operation is completed, all traces of slag shall be removed from the deposit, by chipping if necessary, and the deposit and the adjoining base metal shall be wire brushed and cleaned at all points. The requirements shall apply not only to successive layers, but also to successive beads, and to the over lapping area wherever a junction is made on starting a new electrode.

(5)

The welds shall be free from cracks, discontinuity in welding and other defects such as (i) under-size (ii) over-size, (iii) under-cutting and (iv) over-cutting in the case of fillet welds and defects (ii), (iii) & (iv) in the case of butt welds.

All defective welds which shall be considered harmful to the structural strength shall be cut out and rewelded. In case of welded butt joints in steel of thickness upto 50mm the weld joint shall be subjected to radiographic examination as described in IS 1182. All welds shall be cleaned of slag and other deposits after completion. Till the work is inspected and approved painting shall not be done. The surface to be painted shall be cleaned of spatter, rust, loose scale, oil and dirt.

CPWD SPECIFICATIONS 2009

428

APPENDIX C STEEL TUBES FOR STRUCTURAL PURPOSES (Clause 10.13.1) Nominal Bore (mm) 15 20 25

Outside Diameter (mm) 21.3 26.9 33.7

32

42.4

40

48.3

50

60.3

65

76.1

80

88.9

90

101.6

100

114.3

110

127.0

125

139.7

135

152.4

150

165.1

150

168.3

175

193.7

200

219.1

225 250 300 350

244.5 273 323.90 355.60

L means Light

Class H H M H L M H L M H L-1 M H L M H L M H L M H L M H L M H L M H L M H L M H L M H-1 H-2 L M H L M H H H H H

M means Medium

Wall Thickness (mm) 3.2 3.2 3.2 4.0 2.60 3.2 4.00 2.90 3.2 4.0 2.9 3.6 4.5 3.2 3.6 4.50 3.2 4.00 4.8 3.6 4.0 4.8 3.6 4.5 5.4 4.5 4.8 5.4 4.50 4.8 5.4 4.50 4.8 5.40 4.50 4.8 5.40 4.50 4.8 5.40 6.3 4.8 5.40 5.9 4.8 5.60 5.90 5.90 5.90 6.30 8.00

Weight (kg/m) 1.44 1.87 2.41 2.93 2.54 3.10 3.79 3.23 3.56 4.37 4.08 5.03 6.19 5.71 6.42 7.93 6.72 8.36 9.9 8.7 9.63 11.50 9.75 12.2 14.5 13.6 14.50 16.2 15.00 15.90 17.90 16.40 17.50 19.60 17.80 18.90 21.30 18.20 19.40 21.70 25.20 22.40 25.10 27.30 25.40 29.50 31.00 34.70 38.90 49.30 68.60

H means Heavy 429

SUB HEAD 10.0 : STEEL WORK

APPENDIX D SHAPES, WEIGHTS AND DESIGNATION OF MS ROLLED STEEL SECTION Designation Wt kg/m

Situation of Use of Section

T2

1.036

T3 T6

1.14 0.839

F2 F3 F5

1.46 2.28 1.55

F4B

2.28

F7D

1.419

FX6 FZ7

2.52 1.90

FX8 FZ5 K11B

2.31 2.52 1.80

K12 B

2.30

Vertical and horizontal glazing bars for doors and shashes : windows, ventilators glazing bars for door side lights sub dividing bars for fixed length, sash bars for doors, windows and ventilators wheel steel aluminium or wooden beading is used for fixing glasses. Vertical glazing bar for FZ 7 frame Vertical and horizontal glazing bar for standard windows and ventilators. Inner frames for open-in windows. Outer frames for open-in windows. (a) Inner and middle frames in centre-hung ventilators (b) F5 is some times used as inner frames for open-out windows. Also used as inner frame for bottom hung ventilators (c) F8 is also used as outer frame for bottom hung ventilators. Central mullion (meeting bar for shutters) for windows and ventilators using F7D as inner frames, outer frames for openin windows in rainy areas, subdividing bars for openable windows and top-hung ventilators. Inner and outer frames for windows and top hung ventilators, for inner frames for centre-hung ventilators and outer frames for door sidelights. Inner frame for doors Used as outer frame for industrial shashes. Also used for outer frame for wooden doors Outer frames for doors Inner frames for doors (a) Vertical coupling mullion for standard windows (b) Can be used as horizontal coupling bar when openable windows are to be coupled above fixed ones or between two fixed windows. (c) Can also be used as horizontal coupling mullion where windows are not exposed to weather. Horizontal coupling mullion, also known as weather bar, Especially used when the coupled unit is exposed to rain.

CPWD SPECIFICATIONS 2009

430

APPENDIX D SHAPES 9.5

3

8

9.5

9.5

3

3

9.5

8

1R 1R

16 ± .4

2R

1R 22 ± .4

1R

25 ± .4

1R 2R Max.

1R

1R

2R

1R

19 ± .4

1R 2R Max.

3

2R Max.

22 ± .4

22 ± .4 WEIGHT 1.14 Kg/m T3

25 ± .4

1.5

1R

20 ± .4 1R 3

2

12 ± .4

3

22 ± .4

1R

2R max

2R

2R max

WEIGHT 1.46 Kg/m F2

2R

3

2R max

4

3

2

2R

1R

2R

2R

2R 3

2R

1R 2R

4

7

44 ± .8

32 ± .8

3

2R max

1 2R

1R

1

3

4

1R

25 ± .4

7 2R max

2.5 1

13

13 ± .4

3

2R

2R

3

2R max.

2R 1

13 ± .4

WEIGHT 1.038 Kg/m T2

1R

WEIGHT 0.839 Kg/m T6 All dimensions in millimetres

3

20 ± .4

1R

2R 2 3

WEIGHT 1.55 kg/m F5

1R

2R 3

1

WEIGHT 2.28 kg/m F3 All dimensions in millimetres 22 ± .4

22 ± .4 1.5

1

2

7

1R

2

2R 2R max

3

1R

1R

14 1

2R 2R

.2

WEIGHT 1.92 kg/m F8 All dimensions in millimetres

1

2R

13 ± .4

1R

20 ± .8

3

1R

13 ± .4

1R

46 ± .8

2R max

2R

1

5

2R

1R

2R

3 12

1R 2R max

20 ± .4

3

2R max 2R

1R 2R max

8

3 1R

14 ± .4

1R

3

5

5

19 ± .4

2R max

22 ± .4

13 ± .4

3

20 ± .4

3

3

3

2R 2R

1R 1

3

WEIGHT 1.419 kg/m F7D All dimensions in millimetres

WEIGHT 2.28 kg/m F4B

431

SUB HEAD 10.0 : STEEL WORK

APPENDIX D SHAPES 1.2

32 ±.4

22 ± .4

2R max

1.2

3

2R

1

3 1R 1

15 ± .4

29 ± .4 26 ± .4 1R

3

WEIGHT 1.90 kg/m FZ7 All dimensions in millimetres

1.2

3 3.5

3 2R 1R

2R max

4

44 ± .8

2R max 1R

2R

1R

11 ± .4

2R

2R 2R

2R max.

2R

29 ± .4

1R

1R

10

1R .5

33 ±.8

10

3.5

3

1R

WEIGHT 2.52 kg/m FX6

1R 2R

15 ± .4

27 ± .4

1R

1R

2R 1R

3 3.5

1

3 3.5

13 3

2R

.5

.2 29 ± .4 2R max

3

5

2R max 2R

22 ± .4

2R

43 ± .8

2R

1

6

2R

2R max 1R

3.5 21 ± .8

1R

2R 44 ± .8

29 ± .4

3.5

3

1.2

5

22 ± .4

29 ± .4

19

1 1R

3

10

1R

1

1.2

1R 3

2R max 1R

WEIGHT 2.52 kg/m FZ5 All dimensions in millimetres

WEIGHT 2.31 kg/m FX8

3 3

6R

3R

2.5

2R max.

1R 2R max

9 2R

3 1.2

23 ± .4

2R

2R

3

2R

2R 3

3

3

13

2R

15

50 ± .8

3 27 ± .8

3

3 2R 2R

12

1.2

35 ± .8 2R

2R max 2R max

WEIGHT 1.80 kg/m K11B

2R 35 ± .8 WEIGHT 2.30 kg/m K12B

CPWD SPECIFICATIONS 2009

432

3

WELDS AND RIVETS Sub Head : Steel Work Clause : 10

B. BUTT WELDS

A. BEAD WELDS

Toe Weld Face Original Surface of Work Toe

Fusion Zone Root Fusion Zone

C. PLAIN BUTT JOINT

Convex

Concave

D. FILLET WELD

Mitre Z = Depth of Fusion X = Throat Thickness Y = Effective Throat Thickness Z

Z

Z

Lap

Corner

F. FUSION PENETRATION

E. FILLET WELDS 1.5D

Flat Sunk

Z

1.5D

1.5D

1.5D

1.6D

Counter Head

Round Sunk

Counter Head

Pan Head

2.5D

Bend Test

Flattening Test

0.7D

Shank Tail

d = Effective Diametre D = Normal Diametre

G. RIVETS Drawing not to Scale

Fig. 10.1 : Welds and Rivets

433

SUB HEAD 10.0 : STEEL WORK

COLLAPSIBLE STEEL GATE Sub Head : Steel Work Clause : 10.5

20 x 10 x 2 Channel Iron 3.5 kg/m T-Iron 40 x 40 x 6 T Iron 40 x 40 x 6 38 Dia Ball Bearing

Channel 20 x 10 x 2

Flat Iron Hanger Rivets Fixing with Hold Fast to Wall

Flat Iron 20 x 5 Locking Arrangement

Height

Handle

Lock

Handle

Holding Hook

Pulley or 38 mm Ball Bearing

100

FRONT ELEVATION

FRONT ELEVATION

Opening

Channel

100

Pulley or 38 mm Ball Bearing

SECTION

450

Rivets

450

Opening

PLAN

PLAN

Drawing not to Scale All dimensions are in mm

Fig. 10.2 : Collapsible Steel Gate

CPWD SPECIFICATIONS 2009

434

TYPICAL M.S. SHEET SHUTTERS Sub Head : Steel Work Clause : 10.6 & 10.7

C

Pulley 25 φ

Pully Guide Block Wall

Angle Iron M.S. Channel 40 x 40 x 6 Gusset Plate 315 Thick

40 x 40 x 6 Angle Iron

M.S. Sheet 1 Thick

12 Gap Max.

Rivets

1 Thick M.S. Sheet

Handle Angle Iron 40 x 40 x 6

M.S. Channel M.S. Tee 40 x 40 x 6

M.S. Channel Rivets

Pully or Ball Bearing 25 dia

Anchor Bolts

D

SLIDING DOOR SECTION CD Rivets Pully 25 φ

Pin Tee Fixed with Bolts and Nuts

Wall Angle Iron 40 x 40 x 6

40 x 40 x 6 Angle Iron or 10 x 5 M.S. Flat

30 x 6 M.S. Flat or 40 x 40 x 6 Angle Iron Pin Tee Fixed with Rivets

40 x 40 x 6 Angle Iron

(Alternative Type Cleat)

DETAIL AT X

Rivets M.S. Lower Bolt

Gusset Plate 2400 SIDE HUNG

Angle Iron 40 x 40 x 6 M.S. Channel M.S. Plate 1.15 Thick

Pulley or Ball Bearing 25 dia

DETAIL AT Y

Drawing not to Scale All dimensions are in mm

Fig. 10.3 : Typical M.S. Sheet Shutters

435

SUB HEAD 10.0 : STEEL WORK

STEEL DOORS, WINDOWS AND VENTILATORS Sub Head : Steel Work Clause : 10.10

FIXED

SIDE HUNG

Horizontal

BOTTOM HUNG

TOP HUNG

Vertical Pivotted CENTRAL - HUNG

Mullion

Head of Frame

Ventilator Transome Meeting Stile Overall Height of Window

Lock Plate Lock Rail Overall Height of Door

Frame Bottom Rail

Lugs

Glazing Bar Sill Glass Pane Stile

Kick Plate Sill

Bottom Rail COMPOSITE UNIT

Putty

16 Clip

Putty 100 mm GLAZING CLIPS

3

12.5 10 3

45

70 SLOTTED LUG

Fig. 10.4 : Steel Doors, Windows and Ventilators

CPWD SPECIFICATIONS 2009

436

T-IRON DOOR, WINDOW FRAMES Sub Head : Steel Work Clause : 10.11

Lintel Level

Section Frame Plaster

Socket Plate Welded to Frame

Tower Bolt

T Iron Frame

Standard Fitting Welded to Frame Flush Door Shutter Tower Bolt

Teak Ply Packing

G.I. Socket Embedded in Floor Clearance Finished Floor Level

TOP

TOP

BOTTOM

FIXING TOWER BOLT TO SHUTTERS

Drawing not to Scale

Fig. 10.5 : T-Iron Door, Window Frames

437

SUB HEAD 10.0 : STEEL WORK

STEEL DOORS, WINDOWS & VENTILATORS Sub Head : Steel Work Clause : 10.10 Cement Concrete Lintel Plug

Width of Opening Rendering Width of Ventilator Putty Glass

Hold Fast

Cement Mortar Brick Jamb Cement Mortar

Height of Opening

A. FLUSH WITH RENDERING

Height of Ventilator

Wood Screw Putty Glass

A. FLUSH WITH RENDERING Timber Surround

Width of Opening

Fair Face

Putty

Width of Window Hold Fast

Cement Mortar Plaster

B. FLUSH WITHOUT RENDERING

B. FIXING TO WOOD WORK SURROUND

Width of Opening Width of Window

Fair Face

3 Mastic Putty Glass

Height of Window

Glass

Jamb

Width of Opening

Fair Face

Width of Window Putty

Solid Metal Bead

Plug Wood Screw

Glass Jamb Putty Plaster

Wooden or Metal Bead

Wood Screw Jamb

Plaster

C. REBATED WITHOUT RENDERING

C. REBATED WITHOUT RENDERING Width of Opening Width of Door

Glass

Plug

10

Fixing Clip

Glass Rolled Steel Angle

Hold Fast Rolled Steel Angle 3

Mastic

Putty

12.5

Width of Steel Work Opening

Glass Putty

M.S. or Hard Wood Block Mastic Putty

D. REBATED WITH RENDERING

E. FIXING TO STEEL WORK

Drawing not to Scale

Fig. 10.6 : Steel Doors, Windows & Ventilators CPWD SPECIFICATIONS 2009

19

438

FIXING BUTT HINGES TO T-IRON FRAME WITH M.S. FLAT WELDED TO FRAME Sub Head : Steel Work Clause : 10.11 WELDING OF M.S. GRILL & OTHER STEEL WORK

Butt Welded Plaster 12/15 mm

Wall

M.S. 'T' Iron 40 x 40 x 6 mm

90

Steel Screws

Shutter

T Iron Screw Used in Wood Work

Welding for T Iron Frames

Welding

WLDING FOR 'T' IRON FRAMES SKETCH A 25 x 6 mm M.S. flat 100 mm Long

M.S. Butt Hinges

Fillet Weld

ALTERNATIVE METHOD OF FIXING HINGES TO 'T' IRON FRAMES [ DIRECT WELDING THE HINGES TO 'T' IRON FRAMES]

M.S. Flats Plaster 12 / 15 mm Brick Wall

T Iron Frame 40 x 40 x 6 mm

M.S. FLAT WELDED TO M.S. FLAT SKETCH B

Shutter

Screws

Welding M.S. Flat

M.S. Bar

M.S. Butt Hinges 100 x 58 x 1.9 mm Welded Directly with the Frame on Three Sides

Fillet Weld

M.S. BAR WLEDED TO M.S. FLAT

Drawing not to Scale

Fig. 10.7 : Fixing Butt Hinges to T-Iron Frame with M.S. Flat Welded to Frame

439

SUB HEAD 10.0 : STEEL WORK

PRESSED STEEL DOOR & WINDOW FRAMES Sub Head : Steel Work Clause : 10.12

15 15 12 12

T+5 T+5

X X

12

T+5 12

Y

15 Y

Note : (1) *T is the thickness of the Shutter . (2) X and Y are as per Table 2 of I.S. Code 4351. (3) All dimensions in millimetres.

PROFILES OF PRESSED STEEL DOOR FRAMES

M.S. Pressed Angle 20 x 20 x 1.25 mm

Screwing or Welding

ARRANGEMENT AT BASE OF DOOR FRAME

Fig. 10.8 : Pressed Steel Door & Window Frames

CPWD SPECIFICATIONS 2009

440

Sub Head : Steel Work Clause : 10.12 Hinge Screwed with M/C Screw M 5 x 20 CSK

MS Plate 120 x 30 x 6 mm Thick

Door Shutter Wood Screw No. 10

Mortar Guard Sheet 1.25 mm Thick

Door Frame

FIXING OF HINGE TO THE FRAME - SCREWED TO THE M.S. FLAT Hinge Screwed with M/C Screw M 5 x 20 CSK Nut M5

MS Flat 150 X 30 X 2 mm Thick

Door Shutter Wood Screw No. 10

Mortar Guard Sheet 1.25 mm Thick Door Frame

FIXING OF HINGE TO THE FRAME - SCREWED TO THE NUT

FIXING OF HINGE TO THE FRAME

300

150 Head

Lock Strike Plate Buffer (Shock Absorber) 900 - 1100 mm From Finished Floor Level to Center of Lock Strike Plate

Aldrop Hole

DOUBLE LEAF DOOR FRAME

300 Buffer Shock Absorber

SIDE HUNG DOOR FRAME

Drawing not to Scale All dimensions in millimetres

Fig. 10.8 (Contd.) : Location of Shock Absorbers, Lock-Strike Plate and Aldrop

441

SUB HEAD 10.0 : STEEL WORK

FAN CLAMPS Sub Head : Steel Work Clause : 10.14

Top of Slab 75

200

200 25 Min 16

A

32

Distribution Reinforcement

16 17 Ceiling Finish

Tie Bar Main Reinforcement Exposed Loop shall be Painted

50

100

16 mm φ Top of Slab 200

200

75

R.C.C. Slab

R.C.C. Beam Rib

B

32 100 Min Reinforcement Bar Ceiling Finish Exposed Loop shall be Painted

100

50

160 Top Lid 15 th.

Hole for Conduit Entry 1.5 36.5

C

76 73 36.5

Bottom Lid 1.5 Th.

ELEVATION

14

180

12

13

3.3 mm Dia Tapped Hole SECTION 5 140

CIRCULAR CAST IRON BOX 16

PLAN WITHOUT TOP AND BOTTOM LID

Drawing not to Scale All dimensions in millimetres

Fig. 10.9 : Fan Clamps

CPWD SPECIFICATIONS 2009

442

58.5

SUB HEAD : 11.0

FLOORING

CONTENTS Clause No.

Description List of Mandatory Tests

Page No. 447

List of Bureau of Indian Standards Codes

448

11.1

Brick on Edge Flooring

449

11.2

Cement Concrete Flooring

450

11.3

Cement Concrete Flooring with Metallic Hardner Topping

452

11.4

Cement Plaster in Risers of Steps, Skirting & Dado

453

11.5

Cement Concrete Pavement in Courtyard and Terrace, etc.

454

11.6

Terrazo (Marble Chips) Flooring laid in situ

454

11.7

Terrazo (Marble Chips) Skirting in situ

457

11.8

Wax Polishing

457

11.9

Crazy Marble Flooring

458

11.10

Terrazo Tile Flooring

459

11.11

Terrazo Tiles in Risers of Steps, Skirting & Dado

461

11.12

Chequered Tile Flooring

462

11.13

Chequered Tiles in Stair Treads

463

11.14

Acid or Alkali Resistant Tiles

464

11.15

Pressed Ceramic Tiles Flooring

465

11.16

Pressed Ceramic Tile Flooring (Vitrified Tile Flooring)

467

11.17

Fixing of Tile Flooring with Cement based High Polymer Modified Quick Set Adhesive (Water Based)

467

11.18

Pressed Ceramic Tiles in Skirting & Dado.

467

11.19

Marble Stone Flooring

469

11.20

Marble Stone in Risers of Steps and Skirting

470

11.21

Kota Stone Flooring

471

11.22

Kota Stone in Risers of Steps, Skirting & Dado

472

445

SUB HEAD 11.0 : FLOORING

11.23

Red or White Fine Dressed Sand Stone Flooring

472

11.24

Red or White Fine Dressed and Rubbed Sand Stone Flooring

473

11.25

Wooden Flooring

474

11.26

Wood Block Flooring

475

Appendix A

Abrasion Test for Concrete Hardening Compounds

477

Appendix B

Test Requirements and Procedure for Testing Pre-Cast Cement Concrete/Terrazo Tiles

478

Fig. 11.1

Crazy Marble Flooring

479

Fig. 11.2

Chequred Terrazo Tiles

480

CPWD SPECIFICATIONS 2009

446

LIST OF MANDATORY TESTS Material

Clause

1. Terrazzo Tiles

2. 11.10.1 & 11.11.1

Pressed ceramic tiles (for floor & wall)

11.4,11.5 & 11.16

Test

Field/ Laboratory Test

Test Procedure

3. 1. Transverse strength 2. Water absorption 3. Abrasion Atest

4. Laboratory

5. I S: 1237

1. Dimensions and surface quality 2. Physical properties 3. Chemical properties

Laboratory

I S: 13630

447

Min. quantity of material for carrying out the test 6. 5000 Nos. (no testing need be done if total number of tiles of all types of all sizes from all manufacturers used in a work is less than 5000 Nos)

3000 Nos.

Frequency of testing

7. One test for every 10,000 Nos. or part thereof for each type and size from a single manufacturer. (One test to be done even if the number of terrazo tiles of any type and size from a single manufacturers is less than 5000 Nos. provided the total number of terrazo tiles of all types and sizes from all manufacturers used in a work exceed 5000 Nos. 3000 Nos. or part thereof

SUB HEAD 11.0 : FLOORING

LIST OF BUREAU OF INDIAN STANDARDS CODES S.No. 1. 2. 3. 4. 5. 6. 7.

IS No. IS 269 IS 401 IS 451 IS 455 IS 661 IS 702 IS 1124

8. 9. 10.

IS 1130 IS 1141 IS 1200-(Part XI )

11. 12.

IS 1237- Edition 2.3 IS 1322

13.

IS 1443

14.

IS 1489 (Part-I)

15.

IS 1489-(Part II)

16.

IS 1580

17. 18. 19. 20. 21. 22.

IS 2114 IS 2571 IS 3622 IS 3670 IS 4457 IS 5318

23. 24. 25. 26. 27. 28. 29. 30.

IS 5766 IS 8041 IS 8042 IS 8043 IS 8112 IS 12330 IS: 13630 (Part-1 to 15) IS 13712

31.

IS 15622

CPWD SPECIFICATIONS 2009

Subject Specification for 33 grade ordinary portland Cement Code of practice for preservation of timber Technical supply conditions for wood screws Specification for portland slag cement Code of practice for thermal insulation of cold storages Specification for industrial bitumen Method of test for determination of water absortion, apparent specific gravity and porosity of natural building stones Specification for marble (blocks, slabs and tiles) Code of practice for Seasoning of timber Method of measurement of Building and Civil Engineering work (Part 11) paving, floor finishes, dado and skirting Specification for cement concrete flooring tiles Specification for bitumen felts for water proofing and dampproofing Code of practice for laying and finishing of cement concrete flooring tiles Specification for portland pozzolana cement (Part-I) flyash based Specification for Portland pozzolana cement (Part II) calcined clay based Specification for bituminous compounds for water proofing and caulking purpose Code of practice for laying in-situ terrazzo floor finish Code of practice for laying in-situ cement concrete flooring Specification for sand stone (Slab & Tiles) Code of practice for construction of timber floors Acid and/or alkali Resistant tiles. Code of practice for laying of hard wood parquet and wood block floors Code of practice for laying of burnt clay brick floor Specification for rapid hardening portland cement Specification for white portland cement Specification for hydrophobic portland cement Specification for 43 grade ordinary portland cement Specification for sulphate resisting portland cement. Methods of Testing of ceramic tiles Specification for ceramic tiles; definition, classification characteristic and marking Specification for pressed ceramic tile

448

11.0 FLOORING 11.1 BRICK ON EDGE FLOORING 11.1.1 Bricks Bricks of Specified class designations shall be used. These shall conform to the specifications described in Subhead 6.0. Broken bricks shall not be used in flooring except for closing the line. The bricks shall be laid on edge. 11.1.2 Mortar The mortar used shall be as specified (in case of dry bricks flooring fine sand shall be filled in the joints). 11.1.3 Base Concrete 11.1.3.1 Flooring shall be laid on base concrete where so provided. The base concrete shall be provided with the slope required for the flooring. Floors in verandah, courtyard kitchens, baths shall have slope ranging from 1 : 36 to 1 : 48 depending upon locations as decided by the Engineer-in-Charge. Floors in water closet portion shall have slope of 1 : 30 or as decided by the Engineer-in-Charge to drain off washing water. Plinth masonry off-set shall be depressed so as to allow the base concrete to rest on it. 11.1.3.2 If the base is of lean cement concrete, the flooring shall commence within 48 hours of the laying of base, failing which, the surface of base shall be roughened with steel wire brushes without disturbing the concrete. Before laying the flooring the base shall be wetted and smeared with a coat of cement slurry at 2 kg of cement spread over an area of one sqm so as to get a good bond between sub-grade and flooring. 11.1.3.3 Where base concrete is not provided, the earth below shall be properly sloped, watered, rammed and consolidated. Before laying the flooring, it shall be moistened. 11.1.4 Soaking of Bricks Bricks required for flooring shall be perfectly soaked in stacks before use, by profusely spraying clean water at regular intervals for a period of not less than six hours so as to keep them wet to the satisfaction of the Engineer-in-Charge. (In case the joints are to be filled with sand, the bricks need not be soaked). 11.1.5 Laying 11.1.5.1 The bricks shall be laid on the edge, diagonal herring bone bond, or other pattern as specified or directed by the Engineer-in-Charge. 11.1.5.2 Bricks shall be laid on edge on 12 mm thick mortar of specified ratio bed and each brick shall be properly bedded and set home by gentle tapping with trowel handle or wooden mallet. Its inside face shall be buttered with mortar, before the next brick is laid and pressed against it. 11.1.5.3 On completion of a portion of flooring, the vertical joints shall be fully filled from the top with mortar. During laying, the surface of the flooring shall be frequently checked with a straight edge of length at least 2 m, so as to obtain a true plain surface with the required slope. 11.1.6 Joints Bricks shall be so laid that all joints are full of mortar. The thickness of joints shall not exceed 1.0 cm for brick work with bricks of any class designation. All face joints shall be raked to a minimum depth of 15 mm by raking tool during the progress of work when the mortar is still green so as to provide proper key for the plaster or pointing to be done. Where plastering or pointing is not required to be done, the joints shall be struck flush and finished at the time of laying. The face of brick work shall be cleaned on the same day on which brick work is done and all mortar droppings removed promptly. 449

SUB HEAD 11.0 : FLOORING

11.1.7 Curing Brick work shall be protected from rain by suitable covering when the mortar is green. Brick work in cement mortar, shall be kept constantly moist on all faces for a minimum period of seven days. Brick work carried out shall be suitably marked indicating the date on which the work is done so as to keep a watch on the curing period. 11.1.8 Measurements Length and breadth of the flooring shall be measured correct to a cm and area shall be calculated in square metres correct to two places of decimal. Length and breadth shall be measured before laying skirting, dado or wall plaster. No deduction shall be made nor extra paid for voids not exceeding 0.20 sqm. Deduction for ends of dissimilar materials or other articles embedded shall not be made for areas not exceeding 0.10 sqm. Brick flooring when laid in diagonal herring bone bond or other pattern as specified or directed by the Engineer-in-Charge shall be measured separately. 11.1.9 Rate The rate shall include the cost of all materials and labour involved in all the operations described above, including application of cement slurry on base concrete or RCC slab and cleaning of base. Base concrete shall be paid for separately. 11.1.10 Dry Brick Flooring All provisions of para’s 11.1.1 to 11.1.8 will be applicable except that bricks need not be soaked. Bricks will be laid on a bed of 12 mm thick mud mortar laid to required slope. The joints shall be as thin as possible and not exceeding 5 mm which will be filled with fine sand. No curing is to be done. 11.1.10.1 Rate: The rate shall include the cost of all materials and labour involved in all the operations described above. 11.2 CEMENT CONCRETE FLOORING 11.2.1 Cement Concrete Cement concrete of specified mix grade shall be used and it shall generally conform to the specifications described under sub head 4.0 . 11.2.2 Base Concrete 11.2.2.1 Flooring shall be laid on base concrete where so provided. The base concrete shall be provided with the slopes required for the flooring. Flooring in verandah, Courtyard, kitchens & baths shall have slope ranging from 1 : 48 to 1 : 60 depending upon location and as decided by the Engineer-in-Charge. Floors in water closet portion shall have slope of 1:30 or as decided by the Engineer-in-Charge to drain off washing water. Further, necessary drop in flooring in bath, WC, kitchen near floor traps ranging from 6 mm to 10 mm will also be provided to avoid spread of water. Necessary margin to accommodate this drop shall be made in base concrete. Plinth masonry off set shall be depressed so as to allow the base concrete to rest on it. 11.2.2.2 The flooring shall be commenced preferably within 48 hours of the laying of base concrete. The surface of the base shall be roughened with steel wire brushes without disturbing the concrete. Immediately before laying the flooring, the base shall be wetted and a coat of cement slurry @ 2 kg of cement spread over an area of one sqm so as to get a good bond between the base and concrete floor. 11.2.2.3 If the cement concrete flooring is to be laid directly on the RCC slab, the top surface of RCC slab shall be cleaned and the laitance shall be removed and a coat of cement slurry @ 2 kg of cement spread over an area of one sqm so as to get a good bond between the base and concrete floor.

CPWD SPECIFICATIONS 2009

450

11.2.3 Thickness The thickness of floor shall be as specified in the description of the item. 11.2.4 Laying 11.2.4.1 Panels : Flooring of specified thickness shall be laid in the pattern including the border as given in the drawings or as directed by the Engineer-in-Charge. The border panels shall not exceed 450 mm in width and the joints in the border shall be in line with panel joints. The panels shall be of uniform size and no dimension of a panel shall exceed 2 m and the area of a panel shall not be more than 2 sqm. The joints of borders at corners shall be mitred for provision of strips. 11.2.4.2 Laying of Flooring with Strips : Normally cement concrete flooring shall be laid in one operation using glass/aluminium/PVC/brass strips/stainless steel strips or any other strips as required as per drawing or instructions of the Engineer-in-Charge, at the junction of two panels. This method ensures uniformity in colour of all the panels and straightness at the junction of the panels. 4 mm thick glass strips or 2 mm PVC strips or 2 mm aluminium or brass strips shall be fixed with their tops at proper level, giving required slopes. Use of glass and metallic strips shall be avoided in areas exposed to sun. Cost of providing and fixing strips shall be paid for separately. Concreting : Cement concrete shall be placed in the panels and be levelled with the help of straight edge and trowel and beaten with thapy or mason’s trowel. The blows shall be fairly heavy in the beginning but as consolidation takes place, light rapid strokes shall be given. Beating shall cease as soon as the surface is found covered with a thin layer of cream of mortar. The evenness of the surface shall be tested with straight edge. Surface of flooring be true to required slopes. While laying concrete, care shall be taken to see that the strips are not damaged/disturbed by the labourers. The tops of strips shall be visible clearly after finishing with cement slurry. 11.2.4.3 Laying of Flooring without Strips : Laying of cement concrete flooring in alternate panels may be allowed by the Engineer-in-Charge in case strips are not to be provided. Shuttering : The panels shall be bounded by angle iron or flats. The angle iron/flat shall have the same depth as the concrete flooring. These shall be fixed in position, with their top at proper level giving required slopes. The surface of the angle iron or flats, to come in contact with concrete shall be smeared with soap solution or non-sticking oil (Form oil or raw linseed oil) before concreting. The flooring shall butt against the unplastered masonry wall. Concreting : The concreting shall be done in the manner described under 11.2.4.2. The angle iron/ flats used for shuttering, shall be removed on the next day of the laying of cement concrete. The ends thus exposed shall be repaired, if damaged with cement mortar 1 : 2 (1 cement : 2 coarse sand) and allowed to set for minimum period of 24 hours. The alternate panels shall then be cleaned of dust, mortar, droppings etc. and concrete laid. While laying concrete, care shall be taken to see that the edges of the previously laid panels are not damaged and fresh mortar is not splashed over them. The joints between the panels should come out as fine straight lines. 11.2.5 Finishing 11.2.5.1 The finishing of the surface shall follow immediately after the cessation of beating. The surface shall be left for some time, till moisture disappears from it or surplus water can be mopped up. Use of dry cement or cement and sand mixture stiffening the concrete to absorb excessive moisture shall not be permitted. Excessive trowelling shall be avoided. 11.2.5.2 Fresh cement shall be mixed with water to form a thick slurry and spreaded @ 2 kg of cement over an area of one sqm of flooring while the flooring concrete is still green. The cement slurry shall then be properly processed and finished smooth. 451

SUB HEAD 11.0 : FLOORING

11.2.5.3 The edges of sunk floors shall be finished and rounded with cement mortar 1:2 (1 cement : 2 coarse sand) and finished with a floating coat of neat cement. 11.2.5.4 The junctions of floor with wall plaster, dado or skirting shall be rounded off where so specified. 11.2.5.5 The men engaged on finishing operations shall be provided with raised wooden platform to sit on so as to prevent damage to new work. 11.2.6 Curing The curing shall be done for a minimum period of ten days. Curing shall not be commenced until the top layer has hardened. Covering with empty gunnies bag shall be avoided as the colour of the flooring is likely to be bleached due to the remanents of cement dust from the bags. 11.2.7 Precautions Flooring in lavatories and bath room shall be laid only after fixing of water closet and squatting pans and floor traps. Traps shall be plugged while laying the floors and opened after the floors are cured and cleaned. Any damage done to W.C.’s squatting pans and floor traps during the execution of work shall be made good. During cold weather, concreting shall not be done when the temperature falls below 4°C. The concrete placed shall be protected against frost by suitable covering. Concrete damaged by frost shall be removed and work redone. During hot weather, precautions shall be taken to see that the temperature of wet concrete does not exceed 38° C. No concreting shall be laid within half an hour of the closing time of the day, unless permitted by the Engineer-in-Charge. To facilitate rounding of junction of skirting, dado and floor, the skirting/dado shall be laid along with the border or adjacent panels of floor. 11.2.8 Measurement Length and breadth shall be measured before laying skirting, dado or wall plaster. No deduction shall be made nor extra paid for voids not exceeding 0.20 sqm. Deductions for ends of dissimilar materials or other articles embedded shall not be made for areas not exceeding 0.10 sqm. The flooring done either with strips (in one operation) or without strips (in alternate panels) shall be treated as same and measured together. 11.2.9 Rate The rate shall include the cost of all materials and labour involved in all the operations described above including application of cement slurry on RCC slab or on base concrete including roughening and cleaning the surface but excluding the cost of strips which shall be paid separately under relevant item. Nosing of steps where provided shall be paid for separately in running metre. Nothing extra shall be paid for laying the floor at different levels in the same room or courtyard and rounding off edges of sunk floors. In case the flooring is laid in alternate panels, nothing extra shall be paid towards the cost of shuttering used for this purpose. 11.3 CEMENT CONCRETE FLOORING WITH METALLIC HARDENER TOPPING 11.3.0 Wherever floors are required to withstand heavy wear and tear, use of floor hardener shall be avoided as far as possible by using richer mixes of concrete, unless the use of a metallic hardner is justified on the basis of cost. Where metallic hardener topping is used, it shall be 12 mm thick. 11.3.1 Metallic Hardening Compound The compound shall be of approved quality consisting of uniformally graded iron particles, free from non-ferrous metal particles, oil, grease sand, soluble alkaline compounds. Where so directed by the Engineer-in-Charge it shall be tested as described in Appendix A.

CPWD SPECIFICATIONS 2009

452

11.3.2 Base Concrete It shall be as specified in 11.2.2. 11.3.3 Under Layer Cement concrete flooring of specified thickness and mix (mentioned in item for under layer) shall be laid as under layer (11.2.1 and 11.2.4). The top surface shall be roughened with brushes while the concrete is still green and the forms/strips shall be kept projecting up 12 mm over the concrete surface, to receive the metallic hardening compound topping. 11.3.4 Topping This shall consist of 12 mm thick layer of mix 1:2 (1 cement : 2 stone aggregate 6 mm nominal size) by volume or as otherwise specified with which metallic hardening compound is mixed in the ratio of 1 : 4 (1 metallic concrete hardener : 4 cement) by weight. Metallic hardener shall be dry mixed thoroughly with cement on a clean dry pacca platform. This dry mixture shall be mixed with stone aggregate 6 mm nominal size or as otherwise spe