RCC Substructures

8/13/2019 RCC Substructures

http://slidepdf.com/reader/full/rcc-substructures 1/22

RCC SUBSTRUCTURES

BUILDING MANAGEMENT

APPENDIX A MORTARSList of Mandatory Tests for Sand

MaterialClause

Test ield!La"oratory

test

TestPro#edure

Mini$u$%uantity of

Materialor #arryin&Out t'e test

re(uen#yOf

testin&

Sand Bulking of

Sand

Siltcontent

Particlesizedistribution

Field

Field

Field orLaboratoryas decided

by theengineerin-charge

Appendix C

Appendix B

Appendix A

2 cu!

2 cu!

" cu!

#$ery 2 cu!

%r part there%f or !oreFre&uently as'ecided by#ngineer-in-charge(

'o

)*+#$ery "cu!of fineaggregate,sand

re&uired in CC.ork %nly)2+ #$ery / cu!of fine aggregate,sand re&uired forother ite!s(

Appendix A

Test or Parti#le Si)e *Sie+e Analysis,

Apparatus0 Perforated plate sie$es of designation 1( !!3 "(4 !! and fine !esh sie$e of designation 2(56 !!3

*(*/ !!3 6 !icron and * !icron should be used( 7he balance or scale shall be such that it is readable and accurate to (* percent of the .eight of the test sa!ple( Sa!ple0 7he .eight of sa!ple a$ailable shall no be less than the .eight gi$en in the table belo.( 7he sa!ple ofsie$ing shall be prepared fro! the larger sa!ple either by &uartering or by !eans of a sa!ple di$ider( Test Procedure

7he sa!ple shall be brought to an air-dry condition before .eighting and sie$ing ( 7his !ay be achie$ed either bydrying at roo! te!perature or by heating at a te!perature of * degree to ** degree centigrade( 7he air drysa!ple shall be .eighed and sie$ed successi$ely on the appropriate sie$es starting .ith the largest( Care shallbe taken to ensure that the sie$es are clean before use(



#ach sie$e shall be shaken separately o$er a clean tray until not !ore than a trace passes3 but in any case for aperiod of not less than t.o !inutes( 7he shaking shall be done .ith a $aried !otion3 back-.ards and for.ards3 leftno right3 circular clock.ise and anti-clock.ise3 and .ith fre&uent 8arring3 so that the !aterial is kept !o$ing o$erthe sie$e surface in fre&uently changing directions( 9aterials shall not be forced through the sie$e by handpressure3 but on sie$es coarser than 2 !!3 placing of particles is per!itted( Lu!ps of fine !aterial3 if present !aybe broken by gentle pressure .ith fingers against the side of the sie$e( Light brushing of under side of the sie$e

.ith a soft brush !ay be used to clear the sie$e openings( Light brushing .ith a line ca!el hair brush !ay be used on the * !icrons :S sie$e to pre$ent segregation ofpo.der and blinding of apertures( Stiff or .orn out brushes shall not be used to this sie$e to force particles throughthe !esh( %n co!pletion of sie$ing the !aterial retained on each sie$e3 together .ith any !aterial fro! the !esh3 shall be.eithed( Re-ortin& of Results

7he results shall be calculated and reported as0

a+ 7he cu!ulati$e percentage by .eight of the total sa!ple passing each of the sie$es3 to the nearest .hole nu!ber0 b+ 7he percentage by .eight of the total sa!ple passing one sie$e and retained on the next s!aller sie$e3 to the nearest (* percent(

A--endi. CBul/in& of ine A&&re&ates!sand *ield Met'ods,

7.o !ethods are suggested for deter!ining the bulking of sand,fine aggregate( 7he procedure !ay be suitably$aried3 if necessary( Both depend on the fact that the $olu!e of inundated sand,fine aggregate is the sa!e if thesand,line aggregate .ere dry( 9ethod *0 Put sufficient &uantity of sand loosely into a container until it is about t.o-third full( Le$el off the top ofthe sand and push a steel rule $ertically do.n through the sand at the !iddle to botto!3 !easure the height(Suppose this is ;<= c!( #!pty the sand out of the container into another container .here none of it is lost( >alf fill the first container .ith.ater( Put back about half the sand and rod it .ith a steel rod3 about 6 !! in dia!eter3 so that its $olu!e isreduced to a !ini!u!( 7hen add the re!ainder3 so that its $olu!e is reduced to a !ini!u!( 7hen add there!ainder and le$el the top surface of the inundated sand( 9easure its depth at the !iddle .ith the steel rule(

Suppose this is ;? =c!( 7he percentage of bulking of the sand due to !oisture shall be calculated fro! the for!ula0 Percentage bulking @ )<,?-*+ x * 9ethod 20 :n a 2 !l !easuring cylinder3 pour the da!p sand3 consolidate it by staking until it reaches the 2 !l!ark( 7hen fill the cylinder .ith the .ater and stir the sand .ell )the .ater shall be sufficient to sub!erge the sandco!pletely+( :t .ill be seen that the sand surface is no. belo. its original le$el( Suppose the surface is at the !arkof ? !l( 7he percentage of bulking of sand due to !oisture shall be calculated fro! the for!ula(

Percentage bulking = (200/Y-1)x 100



A--endi. E

Deter$ination of Parti#le Si)e

7he apparatus3 sa!ple size and test procedure shall be sa!e as specified in sub-head ;9ortars= :n order that the sie$es shall not be o$erloaded3 care !ust be taken no ensure that the !axi!u! sie$e loads

sho.n in table belo. are not exceeded at the co!pletion of sie$ing(

01 CONCRETE 2OR3List of Mandatory Tests for Con#rete 2or/

MaterialClause

Testield!La"oratoryTest

Test Pro#edure

Mini$u$%uantity ofMaterial!2or/ forCarryin& out t'etest

re(uen#y ofTestin&

Stone Aggregate

a+ Percentage of soft or deleterious !aterials

eneral isual:nspection3Laboratory 7est.here #ngineer-:n-charge or asspecified

:S 0 25/6 Pt(::*165

As re&uired#ngineer-:n-charge

For all &uantities

b+ Particle size distribution

Field of Lab ase&uired by#ngineer-:n-charge

Appendix # " c!

For e$ery "cu! or partthereof asdecided byengineer-in-charge

7en percentFine $alue

Laboratory Appendix F " c!

:nitial test subse&uent7est as .henre&uired byengineer -in-Charge

Ce!entConcrete%r rein-ForcedCe!entConcrete

)not leaner than*0506

Slu!p test Field Appendix * c!

* cu!,partthereof or !ore fre&uently asre&uired byengineer-in-charge



Ta"le 04

I1S Ma.i$u$ 5ei&'t for

67 #$ dia sie+e /& 89 #$ dia sie+e /&

" !!54( !!5*( !! or 22(* !!*1 !!*6 !! or **(2 !!1( !!(6 !!"(4 !!5(56!!

*/6"52

*(*(

"(5(2(2

*(*((4((5

A--endi. I2or/ Test or Con#rete : Mandatory La" Test

0;9 %ne sa!ple )consisting of six cubes * < * < *c! shall be taken for e$ery 2 cu! or part these ofconcrete .ork ignoring any part less than cu! or as often as considered necessary by the engineer-in-charge(7he test of concrete cubes shall be carried out in accordance .ith the procedure as described belo.( A register ofcubes shall be !aintained at the site of .ork( 7he casting of cubes3 concrete used for cubes and all otherincidental charges3 such as curing3 carriage to the testing laboratory shall be borne by the contractors( 7he testingfee for the cubes3 if any shall be borne by the depart!ent( 0;0 Test Pro#edure

*-*(* 9ould 7he !ould shall be of size * c! < * c! for the !axi!u! no!inal size of aggregate not exceeding

" !!( For concrete .ith aggregate size !ore than " !!3 size or !ould shall be specified by the engineer-in-charge3 keeping in $ie. the fact that the length of size of !ould be about four lines the size of aggregate( 7he !ould for test speci!ens shall be !ade of non-absorbent !aterial and shall be substantially strong enough tohold their for! during the !oulding of test speci!ens( 7hey shall not e$ery fro! the standard di!ensions by !orethan one percent( 7he !oulds shall be constructed that there is no leakage of .ater fro! the test speci!en during!oulding( All the cube !oulds for particular site should3 prior to use3 checked for accuracy in di!ensions andgeo!etric for! and such test should at least be !ade once a year( #ach !ould shall be pro$ided .ith a base plate ha$ing a place surface and !ade of non-absorbent !aterial( 7hisplate shall be large enough in dia!eter to support the !oulds property .ithout leakage( lass plates not less than6( !! thick or plain !etal not less than *2 !! thick shall be used for this purpose( A si!ilar plate shall bepro$ided for co$ering the top surface of the test speci!en .hen !oulded( Dote0 Satisfactory !oulds can be !ade fro! !achine or steel castings3 rolled !etal plates or gal$anized iron( 0101< Sa$-le of Con#rete

Sa!ples of concrete for test speci!en shall be taken at the !ixer or in the case of ready !ixed concrete fro! thetransportation $ehicle discharge or as directed by engineer-in-charge( Such sa!ple shall be obtained by repeatedlypassing a scoop or pail through the discharge strea! of concrete( 7he sa!pling operation should be spread o$ere$enly to the entire discharging operation( 7he sa!ples thus obtained shall be transported to the place of!oulding of the speci!en( 7he counteract segregation3 the concrete shall be !ixed .ith a sho$el until it is unifor!in appearance( 7he location in the .ork of the batch of concrete thus sa!pled shall be noted for furtherreference( :n case of pa$ing concrete3 sa!ples shall be taken fro! the batch i!!ediately after deposition of thesubgrade( At least fi$e sa!ples shall be taken fro! different portion of the pile and these sa!ples shall be



thoroughly !ixed before being used to fro! the test speci!en( 7he sa!pling shall be spread as e$enly aspossible through out the day( Ehen side changes occur during concreting3 additional sa!ples shall be taken if sodesired by the engineer-in-charge(

1.1.3 Preparation of e!t "peci#en!

7he interior surfaces of the !ould and base plate shall be lightly oiled before the concrete the concrete is placed in

the !ould( 7he sa!ples of concrete obtained as described under the test speci!en shall be i!!ediately !ouldedby one of the follo.ing !ethods as indicated belo.0 Ehen the 8ob concrete is co!pacted by !anual !ethods3 the test speci!en shall be !oulded by placing the freshconcrete in the !ould in three layers3 each approxi!ately one-third of the $olu!e of the !ould( :n placing eachscoopful of concrete the scoop shall be !o$ed around the top edge of the !ould as the concrete there sides fro!it3 in order to ensure a unifor! distribution of concrete .ithin the !ould( #ach layer shall be rodded 5 ti!es .ith *6!! rod3 6 c! in length3 bullet pointed at the lo.er end( 7he strokes shall be distributed in unifor! !anner o$erthe cross section of the !ould and shall penetrate into underlying layer( 7he botto! layer shall be rolled throughoutits depth( After the top layer has been rodded3 the surface of the concrete shall be struck off .ith a tro.el andco$ered .ith a glass plate at least 6( !! thick or a !achined plate( 7he .hole process of !oulding shall becarried out in such a !anner as to preclude the change of the .ater ce!ent ratio of the concrete3 by loss of .atereither by leakage fro! the botto! or o$er flo. fro! the top of the !ould(

Ehen the 8ob concreted is placed by $ibration and the consistency of the concrete is such that the test speci!enscannot be properly !oulded by hand rodding as described abo$e3 the speci!ens shall be $ibrated to gi$e aco!paction corresponding to that to the 8ob concrete( 7he fresh concrete shall be placed in !ould in t.o layers3each approxi!ately half the $olu!e of the !ould( :n placing each scoopful of concrete the scoop shall be !o$edaround the top edge of the !ould as the concrete there sides fro! it3 in order to ensure a sy!!etrical distributionof concrete .ithin the !ould( #ither internal or external $ibrators !ay be used( 7he $ibration of each layer shall notbe continued longer than is necessary to secure the re&uired density( :nternal $ibrators shall be of appropriate sizeand shall penetrate only the layer to be co!pacted( :n co!pacting the first layer3 the $ibrators shall not be allo.edto rest on the botto! of the !ould( :n placing the concrete for the top layer3 the !ould shall be filled to the extentthat there .ill be no !ortar loss during $ibration( After $ibrating the second layer enough concrete shall be added tobring le$el abo$e the top of the !ould( 7he surface of the concrete shall then be struck off .ith a tro.el andco$ered .ith a glass or steel plate as specified abo$e( 7he .hole process of !oulding shall be carried out in such

a !anner as to preclude the alteration of .ater-ce!ent ratio of the concrete by loss of .ater3 either by leakagefro! the botto! or o$er flo. fro! the top of the !ould( 1.1.$ %uring and "torage of e!t "peci#en

:n order to ensure reasonably unifor! te!perature and !oisture conditions during the first 2" hours for curing thespeci!en and to protect the! fro! da!age3 !oulds shall be co$ered .ith .et stra. or gunny sacking and placedin a storage box so constructed and kept on the .ork site that its air te!perature .hen containing concretespeci!ens shall re!ain 22 degree C to 55 degree C( %ther suitable !eans .hich pro$ide such a te!perature and!oisture conditions !ay be used( &ote :t is suggested that the storage box be !ade of 2 !! dressed tongued and groo$ed ti!ber3 .ell braced.ith battens to a$oid .arping( 7he box should be .ell painted inside and outside and should be pro$ided .ith a

hinged co$er and padlock( 7he test speci!en shall be re!o$ed fro! the !oulds at the end of 2" hours and stored in a !oist condition at ate!perature .ithin 2" degree C to 5 degree C until the ti!e of test( :f storage in .ater is desired3 a saturated ti!esolution shall be used( 0=017 Testin&

7he speci!ens shall be tested in accordance .ith procedure as described belo.0 a+ 7he tests shall be !ade at an age of concrete corresponding to that for .hich the strength are specified(

b+ Co!pression tests shall be !ade i!!ediately upon re!o$al of the concrete test speci!en



fro! the curing roo! i(e( the test speci!en shall be loaded in da!p condition( 7he di!ensions of the test speci!ens shall be !easured in !! accurate to ( !!( c+ 7he !etal bearing plates of the testing !achine shall be placed in contact .ith the ends of the test speci!ens( Cushoning !aterials shall not be used( :n the case of cubes3 the test speci!en shall be placed in the !achine in such a !anner that the load is applied to sides of the speci!ens at cast( An ad8ustable bearing block shall be used to trans!it the load to the test speci!en( 7he size of the bearing block shall be the sa!e or slightly larger than that of

test speci!en( 7he upper or lo.er section of the bearing block shall be kept in !otion as the head of the testing !achine is brought to a bearing on the test speci!en( d+ 7he load shall be applied axially .ithout shock at the rate of approxi!ately *" kg( S& c! per !inute( 7he total load indicated by the testing !achine at failure of test speci!en shall be

recorded and the unit co!pressi$e strength is calculated in kg per s&(c! using the area co!puted fro! the !easured di!ensions of the test speci!en( 7he type of failure and

appearance of the concrete shall be noted(

A--endi. 3Re&ister of 2or/ Test of Con#rete

Con#rete $i.*"y +olu$e,

Co$-ressi+e stren&t'In /&!#$8 on 4 days

a+ Da!e of .orkb+ Da!e of contractor c+ Agree!ent Do(d+ Sa!ple Do(e+ :dentification !arkf+ Portion of .ork and &uantity represented by sa!ple

g+ 'ate and ti!e of casting cubeh+ Proportion of !ix

*0*02

*0* 05

*020"

2*

*4

*"

4 days 7est----------------

Cube Do

*( 'ue 'ate of 7est2( Actual date of test

5(a+ 9ini!u! strengthb+9axi!u! strengthc+A$erage strength of three cubes

d+'ifference bet.een 5 )a+ 5 )b+e+'ifference in percentage in ter!s of a$erage strength

5b-5a

i(e( -------- < * @ 5c

"( Specified co!pressi$e strength of concrete !ix used Sa!ple is not acceptable3 then 2/ days=strength test shall be



( a+ :f 5 )e+ is !ore than 5G carried out(b+ :f 5 )e+ is e&ual to or less that 5G than proceed as belo.0

i+ 'ifference bet.een colu!n "3 i(e( specified co!p( Strength and colu!n 5 H3 i(e( actual a$erageis higher3 it .ill be denoted )I+ and )-+ if it is less(

ii+ 'ifference in colu!n )b+ )i+ in 5)c+-)"+ < *G

"ter!s of Gage of specified strength

iii+ :f the different in col( )b+ )i+ is I $e and Acceptable and strength is considered in order the sa!e in ter!s of Gage of specifiedstrength )"+3 i(e( $alue of col( )b+ )ii+ is .ithin)I *G range+

J# A#,A## A##a+ Da!e of .ork Concrete 9ix Co!pressi$e strength

)by $olu!e in Kg,c! on 2/ daysb+ Da!e of contractor *0*02

5*c+ Agree!ent Do(d+ Sa!ple Do( *0* 05 26e+ :dentification .ork

f+ Portion of .ork and &uantity representedby sa!ple *020" 2*

a+ 'ate and ti!e of casting cube

b+ Proportion of !ix 2/ 'ays= 7est ----------------- Cube Do

*( 'ue date of test2( Actual date of test5( Actual co!p( Strength of cubes)9in Do( of cubes to be tested-three+a+ 9ini!u! strengthb+ 9axi!u! strengthc+ A$erage strength of three cubesd+ Specified co!pressi$e strength of concrete !ix usede+ 4G of specified strength i(e( 4G of 5 )d+f+ *5G of specified strength( :(e(*5G of 5)d+ "( :f 5 )b+ @ 5 )f+ and 5 )a) 5 )e+ alue of 5 )c+ shall be co!pressi$e strength of sa!ple

( :f 5 H is !ore than 5 )f+ ## !ay order further in$estigation6( :f any test $alue exceeds 5 )f+ :t should be restricted 5)f+ for co!putation of strength4( :f 5 H 5 )d+ but )f+ Strength is in order and concrete accepted at full rates(/ :f 5 H 5 )d+ and )e+ Concrete !ay be accepted at reduced rates1( :f 5 H 5 )e+ Eork representated by this sa!ple shall be re8ected Action taken as prescribed(



CONCRETING*( 7he concrete shall be as specified( 7he proportion by $olu!e of ingredients shall be as specified( 2( Consistency0 7he concrete .hich .ill flo. sluggishly into the for!s and around the reinforce!ent .ithout any segregation of coarse aggregate fro! the !ortar3 shall be used( 7he consistency shall

depend on .hether the concrete is $ibrated on or hand ta!ped( :t shall be deter!ined by slu!p test as prescribed(

Ehere considered necessary3 the .orkability of the concrete !ay also be ascertained by co!pacting factor test and ## B## consisto!eter !ethod specified in :S 0 **11-*11( For suggested ranges of $alues of .orkability of concrete by the abo$e t.o !ethods3 reference !ay be !ade to :S "6-*14/( 5( Placing of concrete

5(* Concreting shall be co!!enced only after engineer-in-charge has inspected3 shuttering and reinforce!ent as placed and passed the sa!e3 shuttering shall be clean and free fro! all

sha$ings3 sa. dust3 pieces of .ood3 or other foreign !aterial and surfaces shall be treated as

prescribed in ' )6+( 5(2 :n case of concreting of slabs and bea!s3 .ooden plank or cat .alks of che&uerred 9S plates or ba!boo chalies or any other suitable !aterial supported directly on the centring by !eans of .ooden blocks or lugs shall be pro$ided to con$ey the concrete to the place of deposition .ithout

disturbing the reinforce!ent in any .ay( Labour shall not be allo.ed to .alk o$er the reinforce!ent( 5(5 :n case of colu!ns and .alls3 it is desirable to place concrete .ithout construction 8oints( 7he progress of concreting in the $ertical direction3 shall be restricted to one !etre per hour( 5(" 7he concrete shall be deposited in its final position in a !anner to preclude segregation of ingredients( :n deep trenches and footings concrete shall be placed through chutes or as directed by the engineer-in-charge( :n case of colu!ns and .alls3 the shuttering shall be so ad8usted that the $ertical drop of concrete is not !ore than *( !etres at a ti!e( 5( 'uring cold .eather3 concreting shall not be done .hen the te!perature falls belo. "( degree C( 7he concrete placed shall be protected against frost by suitable co$ering( Concrete da!aged by forst shall be re!o$ed and .ork redone( 5(6 'uring hot .eather precaution shall be taken to see that the te!perature of .et concrete does not

exceed 5/ degree C( Do concrete shall be laid .ithin half an hour of the closing ti!e of the day unless per!itted by the engineer-in-charge( 5(4 :t is necessary that the ti!e bet.een !ixing and placing of concrete shall not exceed 5 !inutes so that the initial setting process is not interfered .ith( "( Compaction

"(* Concrete shall be co!pacted into dense !ass i!!ediately after placing by !eans of !echanical $ibrators designed for continuous operations( 7he engineer-in-charge !ay3 ho.e$er3 relax this conditions at his discretion for certain ite!s depending on the thickness of the !e!bers and feasibility of $ibrating the sa!e and per!it hand co!paction instead( >and co!paction shall be done .ith the help of ta!ping rods so that concrete is thoroughly co!pacted and co!pletely

.orked around the reinforce!ent e!bedded fixtures3 and into corners of the for!( 7he layers of concrete shall be so placed that the botto! layer does not finally set before the top layer is placed( 7he $ibrators shall !aintain the .hole of concrete under treat!ent in an ade&uate state of

agitation3 such that deaeration and effecti$e co!paction is attained at a rate co!!ensurate .ith the supply of concrete fro! the !ixers( 7he $ibration shall continue during the .hole period occupied by placing of concrete3 the $ibrators3 being ad8usted so that the center of $ibrations

approxi!ates to the center of the $ibrations approxi!ates to the center of the !ass being



co!pacted at the ti!e of placing( "(2 Concrete shall be 8udged to be properly co!pacted3 .hen the !ortar fills the spaces bet.een the coarse aggregate and begins to crea! up to for! an e$en surface( Ehen this condition has been attained3 the $ibrator shall be stopped in case of $ibrating tables and external $ibrators( :n case both internal and external $ibrators are being used3 the internal $ibrators shall be stopped so that no loose pocket is left in the body of the concrete( 7he specific instructions of the !akers of the particular type of $ibrator used shall be strictly co!plied .ith( Shaking of reinforce!ent for the

purpose of co!paction should be a$oided( Co!paction shall be co!pleted before the initial setting starts3 i(e( .ithin 5 !inutes of addition of .ater to the dry !ixture( 5. Construction Joints

(*( Concreting shall be carried out continuously upto the construction 8oints3 the position and details of .hich shall be as sho.n in structural dra.ing or as directed by engineer-in-charge( Du!ber of such 8oints shall be kept to !ini!u!( 7he 8oints shall be kept at places .here the shear force is the !ini!u!( 7hese shall be straight and shall be at right angles to the direction of !ain reinforce!ent( (2 :n case of colu!ns the 8oints shall be horizontal and * to * c! belo. the botto! of the bea! running into the colu!n head( 7he portion of the colu!n bet.een the stepping off le$el and the top of

the slab shall be concreted .ith the bea!( (5 Ehen stopping the concrete on a $ertical plane in slabs and bea!s3 and appro$ed stop-board shall be placed .ith necessary slots for reinforce!ent bars or any other obstruction to pass the bars freely .ithout bending( 7he construction 8oints shall be keyed by pro$iding a triangular or

trapezoidal fillet nailed on the stop-board( :nclined or feather 8oints shall not be per!itted( Any concrete flo.ing through the 8oints of stop-board shall be re!o$ed soon after the initial set( Ehen concrete is stopped on a horizontal plane3 the surface shall be roughened and cleaned after the initial set( (" Ehen the .ork has to be resu!ed3 the 8oint shall be thoroughly cleaned .ith .ire brush and loose particles re!o$ed( A coat of neat ce!ent slurry at the rate of 2(4 kg of ce!ent per s&uare !eter shall then be applied on the roughened surface before fresh concrete is laid(

( Expansion Joints #xpansion 8oints shall be pro$ided as sho.n in the structural dra.ings or as directed by engineer-in-charge3 for the purpose of general guidance( >o.e$er it is reco!!ended that structures exceeding " ! in length shall be di$ided by one or !ore expansions 8oints( 7he filling of these 8oints .ith bitu!en filler3 bitu!en felt or any such !aterial and pro$ision of copper plate3 etc( shall be taken upto t.o places of deci!al stating the depth and .idth of 8oint( (6 Curing After the concrete has begun to harden3 i(e( about * to 2 hours after it laying3 it shall be protected fro! &uick drying by co$ering .ith !oist gunny bags and can$as M hessian or any other !aterial appro$ed by the engineer-in-charge( After 2" hours of laying of concrete3 the surface shall be cured of ponding .ith .ater for a !ini!u! period of 4 days fro! the date of placing of concrete( 5.7. Finishing

(4(* :n case of roof slabs the top surface shall be finished e$en and s!ooth .ith .ooden tro.el before the concrete begins to set( (4(2 :!!ediately on re!o$al of for!s3 the CC .ork shall be exa!ined by the engineer-in-charge3 before any defects are !ade good(

a+ 7he .ork that has sagged or contains honey co!bing to an extent detri!ental to structural safety or architectural concept shall be re8ected by $isual inspection test(

b+ Surface defects of a !inor nature !ay be accepted( %n acceptance of such a .ork by the engineer-in-charge3 the sa!e shall be rectified as follo.s0-



*( Surface defects .hich re&uire repair .hen for!s are re!o$ed3 usually consist of bulges due to !o$e!ent of for!s3 ridges at for! 8oints3 hone-co!bed areas3 da!age resulting fro! the stripping of for!s and bolt holes3 bulges and ridges are re!o$ed by careful chipping or tooling and the surface is then rubbed .ith a grinding stone( >oney-co!bed and other defecti$e areas !ust be chipped out3 the edges being cut as straight as possible and perpendicularly to the surface3 or preferably slightly undercut to pro$ide a key at the edge of the patch(

2( Shallo. patches are first treated .ith a coat of thin grout co!posed of one part of ce!ent and one part of fine sand and than filled .ith !ortar si!ilar to that used in the concrete( 7he !ortar is placed in layers not !ore than * !! thick and each layer is gi$en scratch finish to secure bond .ith the succeeding layer( 7he last layer is finished to !atch the surrounding concrete by floating3 rubbing or tooling on for!ed surfaces by pressing the for! !aterial against the patch .hile the !ortar is still plastic( 5( Large and deep patches re&uire tilling up .ith concrete held in place by for!s( Such patches are reinforced and carefully do.elled to the hardened concrete( "( >oles left by bolts are filled .ith !ortar carefully packed into places in s!all a!ounts( 7he !ortar is !ixed as dry as possible3 .ith 8ust enough .ater so that it .ill be tightly co!pacted .hen forced into place(

( 7iered holes extending right through the concrete !ay be filled .ith !ortar .ith a pressure gun si!ilar to the gun used for greasing !otor cars( 6( Dor!ally3 patches appear darker than the surrounding concrete3 possibly o.ing to the presence on their surface of less ce!ent laitance( Ehere unifor! surface colour is i!portant3 this defect shall be re!edied by adding * to 2 percent of .hile Portland ce!ent to the patching !ortar3 the exact

&uantity being deter!ined by trial( 4( 7he sa!e a!ount of cure the !aterial in the patches should be taken as .ith the .hole structure( Curing !ust be started as soon as possible after the patch is finished to pre$ent early drying( 'a!p hessian !ay be used but in so!e locations it !ay be difficult to hold it in place( A !e!brane curing co!pound in these cases .ill be !ost con$enient(

c+ 7he exposed surface of CC .ork shall be plastered .ith ce!ent !ortar *05 )* ce!ent 0 5 fine sand+ of thickness not exceeding 6 !! to gi$e s!ooth and e$en surface true to line and for!( Any CC surface .hich re!ains per!anently exposed to $ie. in the co!pleted structure3 shall be considered exposed surface for the purpose of this specification3

Ehere such exposed surface exceeding ( s& ! in each location is not plastered .ith ce!ent!ortar *05 )* ce!ent 0 5 fine sand+ 6 !! thick3 necessary deduction shall be !ade for plastering

not done( d+ 7he surface .hich is to recei$e plaster or .here it is to be 8oined .ith brick !asonry .all3 shall be properly roughened i!!ediately after the shuttering is re!o$ed3 taking care to re!o$e the laitance co!pletely .ithout disturbing the concrete( 7he roughening shall be done by hacking(

Before the surface is plastered( :t shall be cleaned and .etted so as to gi$e bond bet.een concrete and plaster(

CC .ork shall be done carefully so that the thickness of plaster re&uired for finishing the surfaceis not !ore then 6 !!(

e+ 7he surface of CC slab on .hich the ce!ent concrete of !osaic floor is to be laid shall be

roughened .ith brushes .hile the concrete is green( 7his shall be done .ithout disturbing the concrete(



5.8 Strength of Concrete

7he co!pressi$e strength on .ork tests for different !ixes shall be as gi$en in 7able 22(

Ta"le <<

Concrete 9ix )nor!al

9ix%n olu!e basis+

Co!pressi$e strength in

)Kg,s& c!+

4 days 2/ days

*0*02*0* 05*020"

2**4*"

5*262*

5.9 Testing of Concrete

010 egular !andatory tests on the consistency and .orkability of the fresh concrete shall be done achie$e the specified co!pressi$e strength of concrete( 7hese .ill be of t.o types(

a+ 9andatory lab test

b+ 9andatory field test esults of 9andatory Field 7est .ill pre$ail o$er !andatory lab( 7est( 71>101 a+ Eork test-!andatory lab( 7est shall be carried out as prescribed in Appendix : b+ 9andatory field test )ha!!er test+3 shall be carried out as prescribed in Appendix J (1(2 dditional Test 0 Additional test3 if re&uired3 shall be carried out as prescribed in Appendix L (1(5 Slump Test 0 7his test shall be carried out as prescribed in Appendix ( (1(" !isual "nspection Test 0 7he concrete .ill be inspected after re!o$al of the for! .ork( 7he &uestion of carrying out !andatory test or other tests described in Appendix L .ill be arise only

after satisfactory report of $isual inspection( 7he concrete is liable to be re8ected if

i+ :t is porous or honeyco!bed ii + :ts placing has been interrupted .ithout pro$iding a proper construction 8oint( iii+ the reinforce!ent has been displaced beyond tolerance specifiedN or construction tolerances

ha$e not been !et(

>o.e$er3 the hardened concrete !ay be accepted after carrying out suitable re!edial !easures to be satisfactionof the engineer-in-charge at the risk and cost of the contractor(

5.#$ "tandard of Acceptance

(*(# %andator& 'a(orator& test 0 For concrete sa!pled and tested as prescribed in Appendix the follo.ing re&uire!ent shall apply( 0*02 %ut of six sa!ple cubes3 three cubes shall be tested at 4 days and re!aining three cubes at 2/ days3 if found necessary( (*(5(4 days tests( Sampling) 7he a$erage of the strength of three speci!en shall be accepted as the co!pressi$e strength of theconcrete pro$ided the $ariation in strength of indi$idual speci!en is not !ore than I *G of the a$erage( 'ifferencebet.een the !axi!u! and !ini!u! strength should not exceed 5G of a$erage strength of three speci!en( :fthe difference bet.een !axi!u! and !ini!u! strength exceeds 5G of the a$erage strength3 then 2/ days ;testshall ha$e to be carried out(



Strength) :f the actual a$erage strength of sa!ple accepted in para ;sa!pling= abo$e is e&ual to or higher thanspecified strength upto *G then strength of the concrete shall be considered in order( :n case the actual a$erage strength of sa!ple accepted in the abo$e para is lo.er than the specified or higher by!ore than *G then 2/ days test shall ha$e to be carried out to deter!ine the co!pressi$e strength of concretecubes(

5.#$.* +8 da&s test

a+ 7he a$erage of the strength of three speci!en be accepted as the co!pressi$e strength of the concrete pro$ided the strength of any indi$idual cube shall neither be less than 4G nor higher than *5G of the specified strength( b+ :f the actual a$erage strength of accepted sa!ple exceeds specified strength by !ore than 5G3 the engineer-in-charge3 if he so desires3 !ay further in$estigate the !atter( >o.e$er3 if the strength

of any indi$idual cube exceeds !ore than 5G of specified strength3 it .ill be restricted to *5G only for co!putation of strength( c+ :f the actual a$erage strength of accepted sa!ple is e&ual to or higher than specified strength upto 5G then strength of the concrete shall be considered in order and the concrete shall be

considered in order and the concrete shall be accepted at full rates( d+ :f the actual a$erage strength of accepted sa!ple is less than specified strength but not less than 4G of the specified strength3 the concrete !ay be accepted at reduced rate at the discretion of engineer-in-charge( e+ :f the actual a$erage strength of accepted sa!ple is less then 4G of specified strength3 the engineer-in-charge shall re8ect the defecti$e portion of .ork represented by sa!ple and nothing shall be paid for the re8ected .ork( e!edial !easures necessary to retain the structure shall be taken at the risk and cost of contractor( :f ho.e$er3 the engineer-in-charge so desires3 he !ay order additional tests )see Appendix L+ to be carried out to ascertain if the structure can be retained( All the charges in connection .ith these additional tests shall be borne by the contractor(

5.##. %easurement

(**(* 'i!ensions shall be !easured nearest to a c! except for the thickness of slab .hich shall be !easured correct to ( c!( 7he areas shall be .orked out nearest to (* s&( !t( 7he cubical

contents shall be .orked out to nearest (* cubic !etre( (**(2 einforced ce!ent concrete .hether cast-in-situ or present shallbe classified and !easured separately as follo.s( a+ aft3 footing3 bases of colu!ns3 etc( and !ass concrete( b+ Ealls )any thickness+ including attached pilasters3 buttresses3 plinth and string course3 fillets3 etc( c+ Suspended floors3 roofs3 landings and balconies d+ Shel$es

e+ Cha88as f+ Lintel bea!s and bressu!!ers( g+ Colu!ns3 pillars3 piers3 abut!ents3 posts and struts( h+ Staircases including .aist or .aist less slab but excluding landing except in )i+ belo.( i+ Spiral staircases )including landing+ 8+ Arches3 arch ribs3 do!es and $aults k+ Chi!neys and shafts l+ Eell steining !+ ertical and horizontal fins indi$idually or for!ing box3 lou$ers and facias( n+ Kerbs3 steps and the like( o+ String course3 bands3 coping3 bed plates3 anchor blocks3 plain .indo. sills and the like( p+ 9ouldings as in cornices .indo. sills3 etc( &+ Shell3 do!e and folded plates(

r+ #xtra for shuttering in circular .ork in plan(



(**(5 Eork under the follo.ing categories shall be !easured separately(

a+ afts3 footings3 basis of colu!ns3 etc( and !ass concrete( b+ All other ite!s upto floor t.o le$el( c+ Fro! floor t.o le$el to floor three le$el and so on( d+ CC abo$e roof le$el shall be !easured along .ith CC .ork in floor 8ust belo.(

(**(" Do deduction shall be !ade for the follo.ing0 a+ #nds of dissi!ilar !aterials3 e(g( 8oists3 bea!s3 post girders3 rafters3 purlins3 trusses3 corbles steps3 etc( upto s&( c! in cross Msection( b+ %pening upto (*( s&(!( c+ 7he $olu!e occupied by reinforce!ent d+ 7he $olu!e occupied by .ater pipes3 conduits3 etc( not exceeding 2 s& c! each in cross

sectional area( Dothing extra shall be paid for lea$ing and finishing such ca$ities and holes( (**( 9easure!ent shall be taken before any rendering is done in concrete !e!bers( 9easure!ent .ill not include rendering( 7he !easure!ent of CC .ork bet.een $arious units shall be regulated as belo.0

a+ Slabs shall be taken as running continuously through except .hen slab is !onolithic .ith

the bea!( :n that case it .ill be fro! the face to face of the bea!( b+ Bea!s shall be !easured fro! face to face of colu!ns and shall include baunches3 if any3

bet.een colu!ns and bea!( 7he depth of the bea! if bea! and slab are not !onolithic( :n case of !onolithic construction .here slabs are integrally connected .ith bea!3 the depth of bea! shall be for! the top of the slab to the botto! of bea!(

c+ 7he colu!ns !easure!ent shall be taken through(

d+ Cha88as along.ith its bearing on .all shall be !easured in cubic !etre nearest to t.o places of deci!al( Ehen cha88a is co!bined .ith intel3 slab or bea!3 the pro8ecting

portion shall be !easured as cha88as3 built in bearing shall be !easured as per ite! oflintel3 slab or bea! in .hich cha88a bears(

e+ Ehere the band and lintels are of the sa!e height and the band ser$es as lintel3 the portion of the band to be !easured as lintel shall be for clear length of opening plus t.ice the o$er all depth of band(



REINORCEMENT*( ,eneral -euirements Steel for reinforce!ent shall be clear and free fro! loose !ilscales3 dust3 loose rust3 coats of paints3 oil or othercoatings .hich !ay destroy or reduce bond( :t shall be stored in such a .ay as to a$oid distortion and to pre$entdeterioration and corrosion( Prior to asse!bly of reinforce!ent on no account any oil substance shall be used forre!o$ing the rust(

*(* ssem(l& of -einforcement 00 Bars shall be bent correctly and accurately to the size and shape as sho.nin the detailed dra.ing or as directed by engineer-in-charge( Preferably bars of full length shall be used( Decessarycutting and straightening is also included( %$er lapping of bars3 .here necessary shall be done as directed by theengineer-in-charge( 7he o$erlapping bars shall not touch each other and these shall be kept apart .ith concretebet.een the! by 2 !! or * O ti!es the !axi!u! size of the coarse aggregate .hiche$er is greater( But .herethis is not possible3 the o$erlapping bars shall be bound together at inter$als not exceeding t.ice the dia of suchbars .ith t.o strands annealed steel .ire of (1 !! to *(6 !! t.isted tight( 7he o$erlaps,splices shall bestaggered as per directions of the engineer-in-charge( But in no case the o$er lapping shall be pro$ided in !orethan G of cross sectional area at one section( *(2 /ands and 0oo1s Forming End nchorages0 einforce!ent shall be bent and fixed in accordance .ithprocedure specified in :S 22-*1653 code of practice for bending and fixing of bars for concrete reinforce!ent(

7he details of bends and hooks are sho.n belo. for guidance(

a+ -7?P# >%%K :n case of !ild steel plain bars standard type hook shall be pro$ided by bending ends of rod into se!icircular hooks ha$ing clear dia!eter e&ual to four ti!es the dia!eter of the bar( 2ote0 :n case of .ork in seis!ic zone3 the size of hooks at the end of the rod shall be eight ti!es the dia!eter ofbar or as gi$en in the structural dra.ing(

b+ B#D'S Bend for!ing anchorage to a 9S plain bar shall be bent .ith an internal radius e&ual to t.o ti!es the dia!eter of the bar .ith a !ini!u! length beyond the bend e&ual to four ti!es the dia!eter of the bar(

*(5 nchoring /ars in Tension0 'efor!ed bars !ay be used .ithout end anchorages pro$ided3 de$elop!entlength re&uire!ent is satisfied( >ooks should nor!ally be pro$ided for plain bars in tension( *(" nchoring /ars in Compression0 7he anchorage length of straight bar in co!pression shall be e&ual tothe ;de$elop!ent length of bars in co!pression( 7he pro8ected length of hooks3 bends and straight lengths beyondbend3 if pro$ided for a bar in co!pression3 shall be considered for de$elop!ent length( *( /inders3 stirrups3 lin1s and the li1e0 :n case of binders3 stirrups3 links etc( the straight portion beyond thecur$e at the end shall be not less than eight ti!es and no!inal size of bar( *(6 4elding of /ars0 Ehere$er facility for electric are .elding is a$ailable3 .elding of bars shall be done inlieu of o$erlap( 7he location and type of .elding shall be got appro$ed by the engineer-in-charge(

+. Placing in Position

2(* Fabricated reinforce!ent bars shall be placed in position as sho.n in the dra.ings or as directed bythe engineer-in-charge( 7he bars crossing one another shall be tied together at e$ery intersection .ith t.o strandsof annealed steel .ire (1 to *(6 !! thickness t.isted tight to !ake the skeleton of the steel .ork rigid so that thereinforce!ent does not get displaced during deposition of concrete( 7rack .elding in crossing bars shall also be per!itted in lieu of binding .ith steel .ire if appro$ed by engineer-in-charge(



2(2 7he bars shall be kept in correct position by the follo.ing !ethods0

a+ :n case of bea! and slab construction precast co$er blocks in ce!ent !ortar *02 )* ce!ent 0 2 coarse sand+ about " < " c! section and of thickness e&ual to the specified co$er shall be placed bet.een the bars and shuttering3 so as to secure !aintain the re&uisite co$er of concrete o$er reinforce!ent(

b+ :n case of cantile$ered and doubly reinforced bea!s or slabs3 the $ertical distance bet.een the

horizontal bars shall be !aintained by introducing chairs3 spacers or support bars of steel at *( !etre or at shorter spacing to a$oid sagging(

c+ :n case of colu!ns and .alls3 the $ertical bars shall be kept in position by !eans of ti!ber te!plates .ith slots accurately cut in the!N or .ith block of ce!ent !ortar *02 )ce!ent 0 2 coarse sand+ or re&uired size suitably ties to the reinforce!ent to ensure that they are in correct position during concreting(

d+ :n case of other CC structure such as arches3 do!es3 shells3 storage tanks3 etc( a co!bination of co$er blocks spacers and te!plates shall be used as directed by engineer-in-charge( 2(5 Tolerance on Placing of -einforcement 0 nless other.ise specified by the engineer-in-charge3

reinforce!ent shall be placed .ith the follo.ing tolerances0

7olerance in spacing

a+ For effecti$e depth3 2 !! or lessb+ For effecti$e depth3 !ore 7han 2 !!

I * !!I * !!

7he co$er shall in no case be reduced by !ore than one third of specified co$er or !! .hich e$er is less( 2(" /ending at Construction Joints0 Ehere reinforce!ent bars are bent aside at construction 8oints and

after.ards bent back into their original position( Care should be taken to ensure that at no ti!e the radius of thebend is less than " bar dia!eters for plain !ild steel or 6 bar dia!eters for defor!ed bars( Care shall also be taken.hen bending back bars to ensure that the concrete around the bar is not da!aged( . %easurement

einforce!ent including authorized spacer bars and lappages shall be !easured in length of different dia!eters3as actually )not !ore than as specified in the drgs+ used in the .ork nearest to a centi!eter and their .eightcalculated on the basis of standard .eight gi$en in 7able 2*( Eastage and unauthorized o$erlaps shall not bepaid for( Annealed steel .ire re&uired for binding or tack .elding shall not be !easured3 its cost being included inthe rate of reinforce!ent( Ehere$er tack .elding is used in lieu of binding3 such .elds shall not be !easured( Chairs separators3 etc( shall

be pro$ided as directed by the engineer-in-charge and !easured separately and paid for(



Ta"le <0 Cross Se#tional Area and Mass of Steel Bar

Do!inal size !! Cross sectional areaS&(!!

9ass per !etreun Kg(

64/*

*2*6*/22222/5256""

2/(55/((54/(6

**5(*2*(22"(65*"(55/(5"1*(*6*6(/"(6*(*/(5*24(2*1*(**16"(5

(22(52(51(6*4

(///*(/2(2("42(1/5(/"(/56(5*4(111(/*2(*("2

Dote0 7hese are as per clause (2 of :S *4/6-*1/

ate0 7he rate for reinforce!ent shall include the cost of labour and !aterials re&uired for all operations describedabo$e such as cleaning of reinforce!ent bars3 straightening3 cutting3 hooking3 bending3 binding3 placing in position3etc( as re&uired or directed including tack .elding on crossing of bars in lieu of binding .ith .ires openings



REINORCED CEMENT CONCRETE#. ,eneral

einforced ce!ent concrete .ork !ay be cast-in-situ or precast as !ay be directed by engineer-in-chargeaccording to the nature of .ork einforced ce!ent concrete .ork shall co!prise of the follo.ing .hich !ay besaid separately or collecti$ely as per the description of the ite! of .ork(

a+ For! .ork )centering and shuttering+ b+ einforce!ent c+ Concreting0 )*+ Cast-in-situ )2 Precast +. %aterials

Eater ce!ent3 fine and coarse aggregate shall be as specified under respecti$e clauses of chapter 5-!ortas andchapter "-concrete .ork as applicable(

5( Form 6or1 )centring and Shuttering+ 5(* Form 6or1 0 For! .ork shall include all te!porary or per!anent for!s or !oulds re&uired for for!ing

the concrete .hich is cast-in-situ3 together .ith all te!porary construction re&uired for their support( 5(2 esign and Tolerance in Construction0 For! .ork shall be designed and constructed to the shapes3 lines and di!ensions sho.n on the dra.ings .ith the tolerance gi$en belo.(

a+ 'e$iation fro! specified 'i!ension of cross section %f colu!ns and bea!s I *2 !!

b+ 'e$iation fro! di!ensions of footing I*2!!

i+ 'i!ension in plan I !! ii+ #ccentricity in plan (2 ti!es the .idth of the

footing in the direction of de$iation but not !ore than !!(

iii+ 7hickness I ( ti!es the specified thickness(

)Dote0 7olerance apply to concrete di!ensions only3 and not to positioning of $ertical steel or do.els+( 5(5 ,eneral -euirement 0 :t shall be strong enough to .ithstand the dead and li$e loads and forces caused by re!!ing the $ibration of concrete and other incidental loads3 i!posed upon it during and after casting of concrete( :t shall be !ade sufficiently rigid by using ade&uate nu!ber of ties and braces3 scre. 8acks or hard board .edges .here re&uired shall be pro$ided to !ake up any settle!ent in the for! .ork either before or during the placing of concrete(

For!s shall be constructed as to be re!o$able in sections in the desired se&uence .ithout da!aging the surface of concrete or disturbing other sections( Care shall be taken to see that no piece is keyed into the concrete(



.* %aterial for Form 4or1

a+ P%PP:D AD' C#D7:D0 All propping and centring should be either of steel tubes .ith extension pieces or built up sections or rolled steel(

b+ C#D7:D,S7A:D0 Staging should be designed .ith re&uired extension pieces as appro$ed by engineer-in-charge to ensure proper slopes3 as per design for slabs,bea!s3 etc( and as per

le$els as sho.n in dra.ings( All the staging to be either to tubular steel structure .ith ade&uate bracings as appro$ed or !ade of built up structural sections !ade fro! rolledstructural steel section(

c+ :n case of structures .ith t.o or !ore floors3 the .eight of concrete3 centring and shuttering

of any upper floors being cast shall be suitable supported on one floor being belo. the top !ost floor already cast(

d+ For! .ork and concreting of upper floor shall not be done until concrete of lo.er floor has set atleast for *" days( 5( Shuttering) Shuttering used shall be of sufficient stiffness to a$oid excessi$e deflection and 8oints

shall be tightly butted to a$oid leakage of slurry( :f re&uired3 rubberized lining of !aterial as

appro$ed by the engineer-in-charge shall be pro$ided in the 8oints( Steel shuttering used for concreting should be sufficiently stiffened( 7he steel shuttering should also be properly repaired before use and properly cleaned to a$oid stains3 honey co!bing3 seepage of slurry through 8oins3 etc(

)a+ -unner oistsSJ3 9S channel or any other suitable section of the re&uired size shall be used as runners(

)b+ Asse!bly of bea! head o$er props( Bea! head is an adopter that fits snugly on the head

plates of props to pro$ide .ider support under bea! botto!s(

5(6 Form) Eork shall be properly designed for self-.eight3 .eight of reinforce!ent3 .eight of fresh

concrete3 and in addition3 the $arious life loads likely to be i!posed during the construction process )such as .ork!en3 !aterials and e&uip!ent+( :n case the height of centring exceeds 5( !etres3 the prop !ay be pro$ided in !ulti-stages(

.7 Cham(er 0 Suitable ca!ber shall be pro$ided in horizontal !e!bers of structure3 especially in cantile$er spans to counteract the effect of deflection( 7he for! .ork shall be so asse!bled as to pro$ide for cha!ber( 7he cha!ber for bea!s and slabs shall be " !! per !etre )* to 2+ or a s directed by the #ngineer-in-charge3 so as to offset the subse&uent deflection( For cantile$ers the ca!ber at free end shall be *,th of the pro8ected length or as directed by the engineer-in-charge(

*. 4alls

7he for! faces ha$e to be kept at fixed distance apart and an arrange!ent of .all ties .ith spacer tubes or bolts is considered best( 7he t.o shutters of the .all are to be kept in place by appropriate ties3 braces and studs(



-emoal of Form 6or1 :Stripping time;

:n nor!al circu!stances and .here ordinary Portland ce!ent is used3 for!s !ay generally be re!o$ed after the expiry of the follo.ing periods(

a+ Ealls3 colu!ns and 2" to "/ hours as !ay $ertical faces of all be decided by the

structural !e!bers engineer-in-charge b+ Sla(i+ Spanning upto "( 9 4 days

ii+ Spanning o$er "( 9 *" days

c+ /eams and archesi+ Spanning upto 6 9 *" days ii+ Spanning o$er 6 9 2* days

upto 1 9iii+ Spanning o$er 1 9 2/ days

Dote *0 For other types of ce!ent3 the stripping ti!e reco!!ended for ordinary portland ce!ent !ay be suitably!odified( :f Portland pozzolana or lo. heat ce!ent has been used for concrete3 the stripping ti!e .ill be *,4 of theperiod stated abo$e( 2ote + 0 7he nu!ber of props left under3 their sizes and disposition shall be such as to be able to safely carry thefull dead load of the slabs3 bea! or arch as the case !ay be together .ith any li$e load likely to occur during orfurther construction( 2ote 0 For rapid hardening ce!ent3 5,4 of abo$e periods .ill be sufficient in all cases except for $ertical side ofslabs3 bea!s and colu!ns .hich should be retained for atleast 2" hours( 2ote *) :n case of cantile$er slabs and bea!s3 the centring shall re!ain till structures for counter acting or bearingdo.n ha$e been erected and ha$e attained sufficient strength(

2ote 5) Proper precautions should be taken to allo. for the decrease in the rate of hardening that occurs .ith alltypes of ce!ent in cold .eather and accordingly stripping ti!e shall be increased( Dote 60 Eork da!aged through pre!ature or careless re!o$al of for!s shall be reconstructed( 6( Surface Treatment 6(* %iling the surface0 Shuttering gi$es !uch longer ser$ice life in the surfaces are coated .ith suitable !ould oil .hich acts both as a parting agent and also gi$es surfaces protections( A typical !ould oil is hea$y !ineral oil or purified cylinder oil containing not less than G pentachlorophenol confor!ing to :S 4*6-*1/4 .ell !ixed to a $iscosity of 4-/ centipoise(

After 5-" uses and also in cases .hen shuttering has been stored for a long ti!e3 it should

be recoated .ith !ould oil before the next use( 6(2 7he design of for! .ork shall confor! to sound engineering practices and rele$ant :S codes( 4( "nspection of Form 4or1

7he co!pleted for! .ork shall be inspected and appro$ed by the engineer-in-charge before the reinforce!ent bars are placed in position( Proper for! .ork should be adopted for concreting so as to a$oid honey co!bing3 blo. holes3 grout loss3 stains or discolouration of concrete etc( Proper and accurate align!ent and profile of finished concrete surface .ill be ensured by proper designing and erection of for! .ork .hich .ill be appro$ed by engineer-in-charge(

Shuttering surface before concreting should be free fro! any defect,deposits and fully

cleaned so as to gi$e perfectly straight s!ooth concrete surface( Shuttering surface should be



therefore checked for any da!age to its surface and excessi$e roughness before use(

4(* Erection of From 4or1 )centring and shuttering+( Follo.ing points shall be borne in !ind .hile checking during erection(

a+ Any !e!ber .hich is to re!ain in position after the general dis!antling is done3 should be clearly !arked(

b+ 9aterial used should be checked to ensure that3 .rong tie!s,re8ects are not used( c+ :f there are any exca$ations nearby .hich !ay influence the safety or for! .orks3 correcti$e

and strengthening action !ust be taken(

d+ i+ 7he bearing soil !ust be sound and .ell prepared and the sole plates shall bear .ell on the ground(

ii+ Sole plates shall be properly seated on their bearing pads or sleepers( iii+ 7he bearing plates of steel props shall not be distorted( i$+ 7he steel parts on the bearing !e!bers shall ha$e ade&uate bearing areas(

e+ Safety !easures pre$ent i!pact of traffic3 scour due to .ater3 etc( should be taken( Ade&uate

precautionary !easures shall be taken to pre$ent accident i!pacts3 etc( f+ Bracing3 struts and ties shall be installed along .ith the progress of for! .ork to ensure

strength and stability of for! .ork at inter!ediate stage( Steel sections )especially deep sections+ shall be ade&uately restrained against tilting3 o$er turning and for! .ork should be restrained against horizontal loads( All the securing de$ices and bracing shall be tightened(

g+ 7he stacked !aterials shall be placed as catered for3 in the design(

h+ Ehen ad8ustable steel props are used3 they should0

*+ be unda!aged and not $isibly bent( 2+ ha$e the steel pins pro$ided the !anufacturers for use(

5+ be restrained laterally near each end( "+ ha$e !eans for centralizing bea!s placed in the forkheads(

i+ Scre. ad8ust!ent of ad8ustable props shall not be o$er extended(

8+ 'ouble .edges shall be pro$ided for ad8ust!ent of the fro! to the re&uired position .here$er any settle!ent,elastic shortening of props occurs( Eedges should be used only at the botto! end of single prop( Eedges should not be too steep and one of the pair should be tight-ended,cla!ped do.n after ad8ust!ent to pre$ent their shifting(

k+ Do !e!ber shall be eccentric upon $ertical !e!ber(

l+ 7he nu!ber of nuts and bolts shall be ade&uate(

!+ All pro$isions of the design and,or dra.ings shall be co!piled .ith(

n+ Cantile$er supports shall be ade&uate(

o+ Props shall be directly under one another in !ultistage constructions as far as possible(

p+ uy ropes or stays shall be tensioned properly(

&+ 7here shall be ade&uate pro$ision for the !o$e!ent and operation of $ibrators and other construction plant and e&uip!ent(

r+ e&uired ca!ber shall be pro$ided o$er long spans(

s+ Supports shall be ade&uate3 and in plu!b .ithin the specified tolerances(



/( %easurements *(* ,eneral 0 7he for! .ork shall include the follo.ing(

a+ Splayed edges3 nothings3 allo.ance for o$erlaps and passing at angle3 sheathing battens3 strutting3 bolting3 nailing .edging3 easing3 striking and re!o$al(

b+ All supports3 struts3 braces3 .edges as .ell as !ud sills3 piles or other suitable arrange!ent to support the for! .ork(

c+ Bolts3 .ire ties3 cla!ps spreaders3 nails or any other ite!s to hold the sheathing together(

d+ Eorking scaffolds3 ladders3 gang.ays3 and si!ilar ite!s(

e+ Filleting to for! stop cha!fered edges of splayed external angles not exceeding 2 !! .ide to bea!s3 colu!ns and the like(

f+ Ehere re&uired3 the te!porary openings pro$ided in the for!s for pouring concrete3 inserting $ibrators3 and cleaning hotels for re!o$ing rubbish fro! the interior of the sheathing before pouring concrete(

g+ 'ressing .ith oil to pre$ent adhesion and

h+ aking or circular cutting(

8.# Classification of %easurements

Ehere it is stipulated that the for! .ork shall be paid for separately3 !easure!ents shall be taken of the area of shuttering in contact .ith the concrete surface( 'i!ensions of the for! .ork shall be !easured correct to a c!( 7he !easure!ents shall be taken separately for the follo.ing(

a+ Foundations3 footings3 bases of colu!ns3 etc( and for !ass concrete and precast shel$es(

b+ Ealls )any thickness+ including attached plaster3 plaster3 butteresses3 plinth and string courses3 etc(

c+ Suspended floors3 roofs3 landings3 shel$es and their supports and balconies(

d+ Lintels bea!s3 girders3 bressu!!ers and cantile$ers

e+ Colu!ns3 pillars3 posts and struts(

f+ Stairs )excluding landings+ except spiral staircase

g+ Spiral staircases )including landings+

h+ Arches

i+ 'o!es3 $aults3 shells roofs3 archribs and folded plates

8+ Chi!neys and shafts

k+ Eell steining

l+ ertical and horizontal fins indi$idually or for!ing box3 lou$ers and bands(

!+ Eaffle or ribbed slabs

n+ #dges of slabs and breaks in floors and .alls )to be !easured in running !etres .here belo.



2 !! in .idth or thickness+

o+ Cornices and !ouldings

p+ S!all surfaces3 such as cantile$ers ends3 brackets and ends of steps3 caps and boxes to pilasters and colu!ns and the like(

&+ Chullah hoods3 .eather shades3 cha88as3 corbels3 et( :ncluding edges and

r+ #le$ated .ater reser$oirs( /(5 Centring3 and shuttering .here exceeding 5( !etre height in one floors shall be !easured and paid for separately( /(" Ehere it is not specifically stated in the description of the ite! that for! .ork shall be paid for separately3 the rate of the CC ite! shall be dee!ed to include the cost of for! .ork( /( Do deductions fro! the shuttering due to the openings,obstructions shall be !ade if the area of such openings, obstructions does not exceed (* s&uare !etre( Dothing extra shall be paid for for!ing such openings(

Documents

RCC Substructures