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“Step Out From the Old to the New”

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“The Right to Information, The Right to Live”

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“Knowledge is such a treasure which cannot be stolen”

“Invent a New India Using Knowledge”

है”ह”ह

IS 10297 (1982): Code of practice for design andconstruction of floors and roofs using precastreinforced/prestressed concrete ribbed or cored slab unit[CED 51: Planning, Housing and pre-fabricated construction]

IS : 10297-1982

Indian Standard Reaffirmed 2008

CODE OFPRACTICE FOR DESIGN AND CONSTRUCTION

OF FLOORS AND ROOFS USING PRECASTREINFORCED/PRESTRESSED CONCRETE

RIBBED OR CORED SLAB UNITS

( First Reprint APRIL 2000 )

UDC 69.024/025: 691.327/.328-412 : 69.001.3

Copyright 1982

BUREAU OF INDIAN STANDARDSMANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG

NEW DELHI 110001

Gr 4

©

1982

IS I 10297· 1982

Indian StandardCODE OF

PRACTICE FOR DESIGN AND CONSTRUCTIONOF FLOORS AND ROOFS USING PRECAST

REINFORCED PRESTRESSED CONCRETERIBBED OR CORED SLAB UNITS

Prefabricated and Composite Construction Sectional Committee, BDe 32

Repr,s,,,tingEngineering Construction Corporation, Madras

DB P. RAY CHAUDHRY

ChairmanSURI A. RAIIAKRISUANA

M""b,r,SUR) S. SUBRAMANIAN ( .,4lt,rnat, to

Shri A. Ramakrishana )ADDliJON.4L DIRECTClR (STAND- Railway Doard ( Ministry of Railways)

ARD) RDSa, LUCXNOWSaRI ASHOX KllJrlAR ( ..4"""al, )

BRIO J. S. AULUW ALIA Ministry of Defence ( Engineer-in-Chief's )LT-COL A. C. MOHAN ( Alt,rnal, )

SHIU C. R ALIKCHANDANJ STUP Consultants Ltd, BombayDR V. N. Gt1N AJ l ( Alt""al,)

DBN. S. BBAL Structural Engineering Research Centre, RoorkeeSHRI K. C. NAITlIANI ( Alternal, )

SHAI AJYA BBARDW A~ In personal capacit y ( 207 Golf Links, New Delh, )SJU\J DAKSDA BBARDWAJ (.141'''''01')

SUBI S. C. CBAKBABARTI CEntral Building Research Insritute (CSIR),Roorkce

Housing &. Urban Development Corporation, NewDelhi

Central Road Research Institute (CS1R») NewDelhi

SBBIB.K.CBAKBADORTY

SHllJ A. K. GABO ( AII,rna',)CBIEF AROHITBC'I' Central Public Works Department, Nt:w Delhi

S, NIOR ARC HlTFCT ( M & TP) ( Alt,rratJt, )DJBFeTOR ( C & MOD) Central "'ater Commission, New Dt'lhi

DJoPUTY DntECTOU ( C & MDD) (Alt,rnate)SHRI A. GB08BAL In pr rsonal capacity (C/o Stup ConsultlllZt.s Ltd, 12

Darga" RODd, Calcutta )DR A. G. MADHAVA RAO Structural Engineering Research Centre, Madra!'

SHRI G. ANNAKAL.AI (..4lt""al,)

( Contirw,J onP(J.~' 2 )

~ ~oR'" ar/" l ~ti2BUREAU OF INDIAN STANDARDS

Thil publication ia protected under the Ind,a" COfl.1';gh' .-4t' (XIV or 1957) andreproduction iD whole or iD part by any me-ana except with writtt·n permission of thepublisher shall b. deemed to be an Infrinlemflot of copyrilht und.r th~ said Act.

18 I 10297 • 1982

( CMtUaud frtJmpa" 1 )

M""HrI R'/Jr,satu.,SRBI G. K. MAJUMDAR Hindustan Prefab Limited, New Delhi

Ssal M. KUNDU ( .41",,,.,. )SJlRJ J S. M\TKt7B Hindustan Steel Works Oon1truction Ltd. CalcuttaSSBI Y. K. MiI-I'l'A The Concrete Association of India, Bombay

SaRI E. T. A!rru. ( ..41''''''', )SRBI P. V. N \I1C Hindustan Construction Co Ltd, Bombay

SHRIA.C.NARWAXl(A.I",uu)SRBJ B. C. PATEL MIs M. N. Dastur at Co Pvt Ltd, CalcuttaSRRI C. M. P ATaL Bihar Prestreeing PVt Ltd, Bbalalpur ( Bihar)SaBI SUllnsa B. PATBL Shirish Patel &. Associates, Bomoay

SURI P. H. SRlNlYA.8A.OBAB ( .tf.lt"nal, )DR V. PABAIIA81VAII Indian Institute of Technologv, MadrasDR N. R \QR \ Y_DBA Cement Research Institute of India, New DelhiPRO.. c. K. RAJI~B Indian Institute of rechnology, BombaySHBI P. V. SHAH Sh:tb Construction Co Ltd, Bombay

SaBT S. R. SlYASW AllY Gammon India Ltd, BombayS 'fBI A. K. CtI.~'l'TBB"BB ( AlIn1l41, )

SHRI K. S. SIi,IJlIVASAJI National Buildings Organization, New DelhiSRRI S UlfIL BRay ( AI,,,,,,,,, )

DR R. C. SONPAL The Instirurion of Engineen ( India ), Calcutta81181 K. VSBRt\BO\GHAVA.OBA.B1 Dbarat Heavy Electricall Ltd, VelloreSHBI G. V IUf'IC ~TIISULU Ministry of Shipping and Transport, Naw Delhi

S ilBl S. S8IDT HABAX A:JI ( Alllrnal, )LT-COL R. G. W \8TBAD Ministry or Defence ( R &. D )

SHBI D. K. MURTHY ( A.l,maau )SRBI G. R AMAR, Director General, lSI ( E¥-oJieio Mmab" )

Director ( Civ EDB' )

S~

SRBI A. K. AVA8TRYAaiatant Director ( Civ Eoa ), lSI

PrefabJ9ication Systems Subcommittee, BDC 32 : 1

CO'IItJItWSBBI G. K. MAJt1IIDAB Hind".tan Prefab Limited, New Delhi

MIrIIHrISBBI M. Ktnmt1 ( .41tmlllll to

Shri G. K. Majumdar)SBBI P. S. AlIs(J[. City and Induttri1,l D~velopment CorporatioD 01

Mabarashtra Ltd, BombaySH'RI P. M. DMU-dD. ( .41,.",.,,)

SHBt E. T. A1fl'IA The Concrete Auociation or India, BombaySKRt N. C. DUGGAL ( AI,,,.,,.,, )

SKBI A. BK,aADWAJ In penonat capacity ( 201Golf Liw. He D11h1)SSRI S. N. CJlA.1fDA Metatlurgfeal & Engineerilll Comultantl (India)

Ltd, RanchiSHBI PASWA'1'BY ( Jflm,"*)

( CMliauMl. /M,' If )2

AMENDMENT NO. 1 DECEMBER 2006TO

IS 10297 : 1981 CODE OF PRACTICE FOR DESIGNAND CONSTRUCTION OF FLOORS AND ROOFSUSING PRECAST REINFORCEDIPRESTRESSEDCONCRETE RIBBED OR CORED SLAB UNITS

(Page 3, clause 0.4) - Insert the following clause at the end:

'o.s All standards, whether given herein above or cross-referred to in the maintext of this standard, are subject to revision. The parties to agreement based onthis standard are encouraged to investigate the possibility of applying the mostrecent editions of the standards. '

(Page 4, clause 2.1, Note) - Substitute the following for the existing note:

'NOTESI The units with nominal width of minimum 300 rom may al80 be used in residentialbuildinp.2 A:I the aize ofthe alab panel units depends on the handling equipment and the design methodnotwithstandingthe size Bivenin 2.1, any other size may be used. '

(Page 6, clause 4.4.3) - Insertthe following note after first para:

'NOTE - For non-circular core sections, the top thickness d1 should be checked for localbendins·'

[Page 7, clause 6.1(a)] - Substitute 'IS nun' for ·12 mm' and '20 mm' for'1' mm'.

(Page 9, clause 7.1) - Substitute the following for the existing firstsentence:

"The concrete mix used shall be minimum of M20 gmde in accordance withIS 456 : 2000 'Code of practice for plain and reinforced concrete (fourthrevision)'. However for prestressed concrete units, higher sttength grade ofconcrete is required in accordance with IS 1343 : 1980 'Code of practice forprestressed concrete(first revlslon)'.1t

1

Amead No. 1 to IS 10297 : 1982

(Page 11,clause 11.5) - Insert the followingat theend:

"However the provisions of IS 1893 (part 1) : 2002 'Criteria for earthquakeresistant design of stnletures: Part 1 General provisions and buildings C/iflhrevision) , and IS 4326 : 1993 'Code of practice for earthquake resistant designand construction of buildings (second revtsiont' for earthquake resistance shallberequired to be taken careor."

(CED 51)

Repro....pby Unit,81S, New Delhi, India

2

IS : 10297 • 1982

Indian StandardCODE OF

PRACTICE FOR DESIGN AND CONSTRUCTIONOF FLOORS AND ROOFS USING PRECAST

REINFORCEDJPRESTRESSED CONCRETERIBBED OR CORED SLAB UNITS

o. F 0 I~ E W 0 R D0.1 This Indian Standard was adopted by the Irulian Standard" Institutionon 30 September 1982, after the draft finalized by the Prclabricated andComposite Construction Sectional Committee had been approved by theCivil Eng.neering Division Council.

0.2 Precast ribbed slab units generally have a thin flange stiffened bylongitudinal and/or transverse ribs. Cored slab units are those precastpanels in which voids are created in manufacturing process to reducethe crass section without appreciably decreasing the stiffness or strength.These ribbed slabs as well as cored slabs are generally lighter than thenormal cast in situ solio slabs or beam and slab. Structurally advant-ageous sections like channels, double tees, hollow core cross sections canbe used, effectinR consic'erably decrease in dead load and resultant savingin material. These units can be used for floors, roofs as well as for wallpanels, in general building construction including residential, public andindustrial buildings. These units can be advantageously used for spansup to 9 metres in caseof reinforced concrete units and up to 30 metresin case of prestressed concrete units.

0.3 In the formulation of this standard due weightage has been given tointernational coordination among the standards and practices prevailingin different countries in addition to relating it to the practices in the fieldin this country.

0.4 For the purpose of deciding whether a particular requirement of thisItandard is complied with, the final value, observed or calculated, ex-pressing the result of a test or ana ysis, shall be rounded off in accordancewith IS : 2·1~ 60•. The number of~ignificant places retained in roundedoft'value should be the lame as that of the specified value in this standard.---._--

·R.ul•• Cor roundiDg off numerical valuft ( ,.",uftl).

3

18 I 10297 • 1982

I. SCOPE

1.1 This standard covers the details of design and construction of floorsan i roofs using precast reinforced and prestressed concrete ribbed/coredslab units. This standard is intended to supplement the requirementsfor design and construction already covered by IS: 456·1978. andIS : 1343·1980f and other relevant codes for reinforced/prestressedconcrete structures.

2. DETAILS OF PRECAST UNITS

2.1 De.I,D Dlme••loa. - The width of the ribbed units may be amaximum of 3000 mm with ClOSS ribs and 2 100 mal for units withoutcross ribs. For residential buildings the nominal width of the unit maybe from 600 mm to I 200 mm in increments of 300 mm chosen as perrelevant standards ani modular coordination. For industrial and otherbuildings, however, the preferred nominal width is 1 500 mm for channelunits and 2 100 mm for double tee units. For the cored slab units thewidth shall be chosen taking into consideration the aspects of modularcoordination as per relevant codes up to a maximum width of 2 100 mm,The actual width of the precast unit will however be slightly less to takeinto consideration the tolerance in casting the units and also to provideCor cast in sitll grouting at the joints.

NOT. - The unit! with nominal width or minimum .300 mm may also be wed inrelidential buildin... .

2.2 The overall depth of the longitudinal ribs shall not be less than 1/25of span for reinforced concrete units and 1/30 of span in the case ofprestressed concrete units. It is, however, recommended that deflectioncalculations in accordance with the relevant Indian Standard code aremade to ensure that these serviceability conditions are met ( s" IS : 456-J978· and IS : 1343-1980t ).

2.3 The minimum width of the rib shall not be less than 50 mm forspans up to 5 m and 70 mm in the case of larger spans, The cross sectionof the rib shall, however, have adequate slopes to facilitate demouldingduring manufacture. Normally, the internal slopes may be in the rangeof 1'15 to 1/8.

2.4 The minimum thickness of flange shall be 35 mm provided the con-creting is done with proper mechanical vibration or by other methods toachieve equivalent compaction assuming that the maximum size ofaggregate shall be 12 mm. It is essential that the reinforcement in theflange shall be provided in the form of a mesh with spacing of bars/wiresnot exceeding those stipulated for slabs in IS : 456-1978* subject to the

*Code or practice for plain and ...,inforced concret. ( thi,d ,,,,isiM).fCode of pracdce Cor pr.tr-.d concrete (fir" ,1ViSiM ).

4

IS I 10297 • 1982

condition that the maximum unreinforced concrete area does not exceed15,2 where t is the thickness of tile f'ange, In the thin units ( of 35 mmthickness ot flange) the spacing may be a maximum of 150 mm bothways.

3. MATERIALS

3.1 The materials used for the construction shall conform to IS : 456-1978· and IS : 1343-1980t.

4. STRUCTURAL DESIGN

4.1 The precast units shall have adequate strength and stability in accor-dance with the relevant code of practice ( IS : 456-1~78· or IS : 1343-1~80t ) during the following stages:

a) Demoulding;b) Handling, stacking, transporting and placing; andc) With all design loads together with dead load of in sit" concrete

placed for connection purposes.

In situations where in situ concrete brings in monolithic connectionand continuity it shall be designed according to IS : 3~35·1£66:.

NOT. - Where Portland pozzolana cement is wed delayed Itrenlth developmeDtat the early .,es shall be considered.

4.2 Loads shall be in accordance with IS : 875-1S64§.

4.3 For calculating the limit state of collapse at the critical cross sections,at Itage of demoulding and handling, a load factor of at lealt 1 5 shallbe applied for calculating the design limit state of collapse load.

The actual strength of the cross section at this stage can either becalculated or proved through necessary tests.

4... meetlve I'IaDle Wldtb

4.4.1 &in.!or"tl Ctme,," Ribbed Slab Units - When the thickness of flangei. more than 1/10 of overall depth of the rib, the overall width of theflange i. effective in the compressive zone and can be taken into constdera-tion in calculations for moment of resistance of the cross sections In casethe thickness of flange is less than 1/10 of the overall depth of the rib, theeffective RanKe width can be taken as in T-~ectjon in accordance withIS : 456-1978*. Typical sketch of the channel unit and double tee unitis shown in Fig. 1.

-Cod. or practice tor plaiD and reinforced concrete ( '/lirtl ,airit" ).tCode of practice ror prrltreaed concrete (first rmsi." ).*Code or practic.. for compoaitp conatructit D.ICode or practice Cor Itructural sarety of buildinls: LoadiD. standards.

5

IS I 10297 • 1982

11. CHANNEL SLAB UNT

'8 DOUBLE TEE aAS UtlT

FlO. 1 RIBBED SLAB UNITS

t.4.2 P"'3"',lItl Coner,', Ribb,dSltJb U"itr - In the design of prestressedribbed slabs, However, the entire flange should be taken as effective for allcases and the T-beam formula should not be applied as this may leadto underestimation of the prestressing force required, if a lesser crosssection is assumed to be effective.

4.4.3 RiinjiJrcid or P"slr,ss,tl Co"d Slab Units - The thickness 'tl' ofcored slab units shan be in accordance with 2.2. The dimension 'tlltshan be at least I tl and 'tIs' shall be at least 1 d ( SI' Fig. 2) subject tominimum of 20 mm.

TOP

1d

------------I-----....IJBOTTOMFlO. 2 CORED SLAB UNIT

The smallest cross-section width excluding the hollow space,

bo ... b - ItJ, .haH be at lealt '1.:' unless a greater width i. required forcontemplated shear stress.

6

IS I 1.7 • 1982

4.4.3.1 R~inforc,d or prestressed cored slab "nils - The effective crosssection for design can be modified by adopting equivalent rectangularlsquare instead of circular or elliptical openings as given in Fig. 3.

5. MOULD

5.1 The mould used for manufacturing ribbed slabs normally consist oftwo parts, (a) bottom mould, ani (b) side moulds. 'I he bottom mouldcan be made out of timber, masonry, concrete, steel, FRP, plastic 0" anyother material acceptable to engineer-in-charge. The side mouldssimilarly can be of timber, steel, FRP, or plastic. When using masonryor concrete moulds, the top surface shall be finished to the requiredaccuracy ( se« Table 1 ) and made smooth.

In case of masonry moulds, the use of chicken mesh or fibrereinforcement in the top surface will help in making the mould lastlonger for higher efficiency.

5.2 In the case of cored slabs, the voids can be created either by anextrusion process, by inflated tubes, mild steel tubes, timber, cardboardjhard paper or any other material.

5.3 The castellationsfdepressionsfroughening of required depth shall beprovided in the sides of the precast units. Suitable provisions in theside shutters of the DaU111d may create better keying between in situconcrete and precast concrete units at the joints.

6. REINFORCEMENT COVER

6.1 Minimum cover for the reinforcement for precast units shall be as£0110\\'5:

a) For reinforcement in the flange, 12 mm clear in all directions.This shall be increased to 15 mm when surfaces of precastmembers are exposed to corrosive atmosphere; and

b) For main reinforcement in the rib, 20 mm or diameter of barwhichever is greater. In case of corrosive atmosphere, thisshall be increased to 25 mm, or diameter of bar, whichever isgreater.

6.2 It shall be ensured that the reinforcement cages are not in any waydistorted during storage, handling, placement and casting. In the caseof mass production in large precasting factories, the use of reinforcementladders and mesh made by usin~ a resistant-welding machine will beadvantageous for improving production.

7

II I 10217 • 1982

_-1-

1-:.1o

8

18 I 10297 • 1982

7. CONCRETE

7.1 The concrete mix used shall be minimum of M-15 grade in accor-dance with IS: 456·1978· but M-20 and above grade of concrete iapreferred for reinforced concrete units and in accordance with IS: 1343-1980t in the case of prestressed concrete units. The maximum size oraggregate used shall be restricted to 12 mm in the case of ribbed slabsand cored slabs with flange thickness less than 50 mm,

8. CASTING AND CURING OP UNITS

8.1 Mechanical vibration either through mould/table vibrators or screedvibrators is essential to ensure good compaction. Needle vibrators canbe used for compacting concrete in the ribs and screed vibrators forcompacting concrete in the flange. For larger factories, concrete placingmachine which level, vibrate and finish the concrete units cain beadvantageously utilized for this purpose.

8.2 Curing shall be done as per IS: 456..1978*. If necessary, lowpressure steam curing may be provided to get early stripping/releasestrength.

t. TOLERANCES

t.1 Tolerances of units shall be as follows.

9.1.1 Ungt" - ±5 mm or ±O·l percent, whichever is greater.

9.1.2 CrDss-S,etional Di",,1Uions - ±3 mm or ±O·l percent, whichever isgreater.

9.1.3 Strai,hlnul of BDW - ±5 mm or 1/750 of the length, whicheveris greater.

9.1.4 Squa"",ss - When considering the squareness of the corner. thelonger of the two adjacent sides being checked shall be taken a. the baseline. The shorter side shall not vary in length from the perpendicularby more than 5 mm,

For the purpose of this requirement any error due to lack ofstraightness shall be ignored; squareness shall be measured with respectto the str'light lines which are mostly nearly parallel with the featuresbeing checked when nominal angle is other than 90°, the included anglebetween the check line. should be varied accordingly.

·Code or practice CorplaiD and r~inrOl'Ced concrete ( ,Ai,d",isi.. ).tcode 01 practice tor pr.tresaed concrete (psI rlflisiOll ).

9

III 10297 • 1982

9.1.5 Twist - Any corner shall not be more than the tolerance givenbelow from the plane containing the other three corners:

Up to 60 cm in width and 5 mmup to 6 mm in length

Over 60 em in width and 10 mmfor any length

9.1.6 Flatness - The maximum deviation from a 1·5-m strair ht edgeplaced in any position on a nominal plane surface shall not exceed 5 mm,

9.2 Tolerances of the mould are given in Table 1.

TABLE 1 TOLERANCES OF MOULDS( Cz'us,s 5.1 IIlId 9.2 )

LengthWidthHeightDiagonalWarp/Bow

(mm)

-10-0-s-o+3-0±S-O±3'O

9.3 Suitable erection tolerances shall be taken into account while erectingthe precut unite,

10. SAMPLING AND TESTING OF UNITS

10.1 SampliD. - Sampling shall be done in accordance withAppendixA.

10.2 Load Te.t

10.2.1 Load tests shall be carried out in accordance with IS: 4~61978-.

10.2.2 All the units passing the load test can be used in the construc-tion.

10.3 After the load test, an optional test on the precast unit up todestruction can be performed as agreed to between the supplier and thepurchaser. This te!t is primarily intended to re-confirm the load-factoractually available rJu-a-rJiI the design load.

-Code or practice lor plaiD and reinforced CODcrete ( ,lirl,.,1M ).

10

IS I 10297• 1982

11. TRANSPORTATION AND ERECTION OP PRECASTELEMENTS

11.1 Llrtla.l Book. - Wherever lifting hooks/holes are used theseshall be provided at structurally advantageous points ( for example, 1/5of the length from the end of the element ) to facilitate demoulding anderection of the precast unit. The lifting hooks can be formed out ofnormal mild steel reinforcing bars with adequate carrying capacity tocarry the self weight during demoulding, handling and erection. Aftererection, the hooks can either be cut or bent down inside the screed orjoint concrete that will be laid subsequently.

11.2 StackiD. of Units - After removal Crom moulds the precastunits shall be stacked over supports placed at about 1/6 of span Cromends. Care shall be taken to see that no support is placed at the centreof span. Care also shall be taken to see that the main reinforcement isalways at the bottom oC stacked units.

11.3 Traa.portatloa - The units shan be transported always with themain reinforcement at the bottom. For transporting and erecting theunits, rope slings shall be tied near the ends at 1/5 of the length fromeither end of the unit. In case the units are transported in trolleys, theover-hang of the units from the trolley shall not be more than 1/5 of thelength. The unit shall be lifted manually or with the help of chainpulley blocks or mechanically with a hoist or a crane.

11.4 PlaciDl .ad AUpl.g - The units shall be placed and alignedside by side across the span to be covered. While placing the units, careshall be taken to see that they have the specified bearing Oil supportingwall/beam. Placing of units shall be started from one end of thebuilding.

11.5 Bearlal - The precast u~itl shall have a minimum bearing of75 mm on the beams and 100 mm on the conventional masonry waU.

11.5.1 If ribbed slab units without end diaphragm are used overconventional masonry wall, concrete bed blocks shall be providedbeneath the rib••

12. CURING OP IN SITU CONCRETE IN JOINTS

12.1 The ira sil" concrete in the joint shall be cured for at least 7 days inaccordance with IS: 456·1978*. The concrete shall then be allowed todry for at least a week. A coat of cement slurry may be applied to tMjoints to fill the hairline cracks that might have developed.

·Code of practicefor plaiD and reinforced concrete ( ,lairdmisi. ).

11

IS I 10297 • 1982

13. FIXTURES

13.1 Designers shall indicate provisions for fixtures like fanhooksjinsertsjelectric conduits, etc, to be incorporated within the precast units or thein situ joints/screed concrete,

13.1.1 In case of concealed wiring, conduits may be placed within thejoints along the length or within the screed before concreting, Ifadequate thickness is available this may be concealed within the floorlroof finish.

13.1.2 Holes, openings and fixtures required to be provided within theprecast units shall be fixed accurately with adequate embeddment at theprecasting stage. Drilling of holes/cutting of edges shall not be madeunless permitted by the engineer-in-charge beforehand.

14. FLOOR FI~ISH

14.1 In case of floor slab, the floor finish shall be done as per therelevant Indian Standard Code of practice. The Indian Patent Stoneor mosaic flooring shall be layed in bays with the bay lines in thedirection of the unit coinciding with any of the joints between the units.

14.2 When the floor is made up of series of strips, mechanical con-nections/screed concrete/overlapping reinforcement may be provided toaccount for differential loading.

14.3 To provide adequate resistance against impacijacourtic treatment,the floor thickness at any place shall not be less than 75 mm.

15. ROOF TREATMENT

15.1 Adequate waterproofing and thermal insulation to suit localclimatic conditions shall be adopted in accordance with relevant Inc..ianStandard Code of practice.

APPENDIX A(Clause 10.1 )

SAMPLING PROCEDURE FOR PRI:CAST SLAB UNITS

A-I. LOT

A-I.I AJI the precast slab units of the same sise, manufactured from thesame materia) under similar conditions of production shall be groupedtogether to constitute a lot.

12

IS I 10297 • 1982

A-l.2 The number of units to be selected from each lot for dimensionalrequirements shall depend upon the size of the lot and shall be inaccordance with coli and 2 of Table 2.

TABLE 2 SAMPLE SIZE AND REJECTION NUMBER

LOT SIZE FIRST SAID'LE SECOND FIRST REJEC- SECOND REJEC-SIZE SAMPLE SIZE TION NUMBER TION NUMBER.

(1) (2) (3) (4) (5)

Up to 100 5 5 2 2101 to 300 8 8 2 2301 to 500 13 13 2 2501 and above 20 20 3 4

A-l.2.1 The units shall be selected from the lot at random. In orderto ensure the randomness of selection, procedure given in IS : 4905-1968*may be followed.

A-2. NUMBER OF TESTS AND CRITERIA FOR CONFORMITY

A-2.1 All the slab units selected at random in accordance with coli and2 of Table 2 shall be subjected to the dimensional requirements. A unitfailing to satisfy any of the dimensional requirements shall be termed asdefective. The lot shall be considered as conforming to the dimensionalrequirements if no defective is found in the sample, and shall be rejectedjf the number of defectives is greater than or equal to the first rejectionnumber. If the number of defectives is less than the first rejectionnumber the second sample of the same size as taken in the first stageshall be selected from the lot at random and subjected to the dimensionalrequirements, The number of defectives in the first sample and thesecond sample shall be combined and if the combined number ofdefectives is less than the second rejection number, the lot shall beconsidered as conforming to the dimensional requirements; otherwisenot.

A-2.2 The lot which has been found as satisfactory with respect to thedimensional requirements shall then be tested for load test. For thispurpose one unit shall be selected for every 300 units or part thereof.'fhe lot shall be considered as conforming to the requirement if all theunits meet the requirement; otherwise not.

·MpthodCl Cor random ~ampling.

13

IS I 10297· 1982

( Continued from page 2 )

Al~nhen Repus'ntmf8HBI N. K. GUPT \ Engin~ers India Ltd, NE'wDelhiSHBI P. C. JAIN Engineer·in-(~hief'sBranch, Army Headquarters

M~J V. B. ARORA ( Alt,r"ate)SHRI MAJlENDRA RAJ Engineering Consultants ( India ), NC'wDC'lhiSHRI G. M. MANDALI.\. Indian Institute of Arrhu('C't" BombavSllKI S. NAHABOY Engineering Construction Corporation Ltd, Madras

SHRI G. B. Srsnn ( Alternat, )SHRt A. NANOY Civengers Enterprise Pvt Ltd, NC',v DelhiSHRI C. M. PATEL Bihar Prestressing Pvt Ltd, BhagalpurDR N. RAGHAVENDRA Cement Research Institute of India, X(aw D

BUREAU OF INDIAN STANDARDS

,.,.---.:MMIlk Shav." g B8hadur Shah zalar Marg, NEW DELHI 110002Telephones: 323 0131, 323 3375, 323 9402Fa : 91 11 3234082, 91 11 3239390, 91 11 3238382

323 78 173378812

803843235 23 15832 9215

Telegrams : Manak.......(Common to all Offices)

Telephone8-77 00 32

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Plot No. 2018, Site I~ Sahlbabad Industrial Area, SAHIBABAD 201010

"""'Ome.:centr81 : Manak Bhavan, 9 Bahadur Shah zafar Marg, NEW DELHI 110002

r -e••rn : 1/14 CIT Scheme VII M, V.I.P. Road, Maniktola, CALCUTTA700054Northern: sea 335-336, Sector 34-A, CHANDIGARH 160022 ...Southern : C loT. campus, IV Cross Road, CHENNAI 600113tweswn : Manakalaya. E9 Behind MarolTelephone Exchange, AncIleri (East),

MUMBAI 400093

.,."." attic.:'Pushpak', Nurmohamed Shaikh M_g, Khanpur, AHMEDABAD 380001~a Indu.trial Area, 1st Stage, Bangalore -1lImkur Road,

BANGALORE 560058GMgotrl Complex, 5th Floor, Bhadbhada Road, T. 1: Nagar. BHOPAL 482003Plot No. 62-63, Unit VI, Ganga Nagar, BHUBANESHWAR 751001Kalalkathlr Buiklngs, 670 Avlnashi Road, COIMBATORE 641037Plot No. 43, Sector 16 A, Mathura Road, FARIDABAD 121001Savttrl Complex, 116 G T Road, GHAZIABAD 2010015315 Ward No. 29, R. G. Barua Road, 5th By-lane, GUWAHATI 7810035-8-58C, L. N Gupta Marg, Nampally Station Road, HYDERABAD soooorE·52, Chltaranjan Marg, C-Scheme, JAIPUR 302001117/411 B, Sarvodaya Nagar, KANPUR 208005Seth Bhawan, 2nd Floor, Behind Leela Cinema, Naval Kishor. Road,

LUCKNOW 228001Patllputra Industrial Estate, PATNA 800013

T. C. No. 14/1421, Unlv_ny P. O. Palay8m,THIRUVANANTHAP~RAM 895034

NIT Butklng, Second Floor, Gokulpat M.-ket, NAGPUA 440010lnatltulon ofE~. ( Incla ) Bulking, 1332 Shlvajl Nagar, PUNE 411005

550 13 48839'855

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54 11 3720 1083

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t8alel Ome. Ie at Novelty ChM1ber., GrMt Road, MUMBAI 400007*8aIeI Oftlce II at 'F' Block. Unity Bulclng, N••himlraja sep.e,

BANCIALORE 510002

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