7 Technical Specification Civil

8/13/2019 7 Technical Specification Civil

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Page 1 of 97,Technical Specifications CivilTender No.10000002-HD-11120,HPCL, NCZ

TECHNICAL SPECIFICATIONS

TECHNICAL SPECIFICATIONS-MATERIALSGENERAL:

(a)All materials to be used in the execution of C ivil & structural worksshall be governed by the requirements of this specification.

(b)Whenever any reference to IS codes is made, the same shall betaken as the latest revision (with all amendments issued thereto) ason the date of submission of the bid.

(c)Apart from the IS codes mentioned in particular in various clauses ofthis specification, for a specific work under consideration all otherrelevant codes regarding quality, testing and/or inspectionprocedures shall be applicable. Reference to some of the codes inthe various clauses of this specification does not limit or restrict thescope of applicability of other referred or relevant codes.

(d)In case of any variation/contradiction in provisions between IScodes and this spec ification, the provisions given in thisspecification shall be followed with the approval of the Engg.-In-Charge (EIC) / Consultant/ Architect.

(e)All materials shall be of standard quality and shall be procured fromrenowned sources/manufac turers approved by the EIC/Architec t/Consultant. It shall be the responsibility of the contractor,to get all materials approved prior to procurement and placementof order.

(f) Quality and acceptability of materials not covered under thisspecification shall be governed by the relevant IS codes. In case IScode is not available for the particular material, other codes e.g. BS

or ASTM shall be considered. The dec ision of the Engg.-In-Charge/consultant/ architect in this regard shall be final and binding on thecontractor.

(g)Whenever asked for, the contractor shall submit representativesamples of materials to the client for inspection and approval.Approval of any sample does not necessarily exempt the


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contractor from submitting necessary test reports for the approvedmaterial, as per the spec ification / relevant IS codes.

(h)The contrac tor shall submit manufac turers test reports on qualityand suitability of any material procured from them and theirrecommendation on storage, application, workmanship etc. for theintended use. Submission of manufacturers test reports does notrestrict the client/consultant from asking for fresh test results from anapproved laboratory of the actual material supplied from anyapproved manufac turer/source at any stage of execution of work.

(i) All costs relating to or arising out of carrying out the tests andsubmission of test reports and or samples to the client/consultant forapproval during the entire tenure of the work shall be borne by thecontrac tor and included in the quoted rates.

(j) Materials for approval shall be separately stored and marked, asdirected by the client/consultant and shall not be used in the workstill these are approved. The c ontrac tor at his own cost shallimmediately remove all rejected materials from the site.

(k)In the event that state, city or other Government bodies haverequirements more stringent than those set forth in this specification,such requirements shall be considered part of this specification andshall supersede this specification wherever applicable.

(l)The quality of materials, method and control of manufac ture andtransportation of all concrete works irrespective of the mix , whetherreinforced or otherwise, shall conform to the applicable portion ofthis specification.

(m) Engineer shall have the right to inspect the source/s of material/s,the layout of operations of procurement and storage of materials.

Such an inspection shall be arranged and approval of Engg.-In-Charge shall be obtained prior to starting of concrete work.

(n) Concrete shall be mixed by mechanical mixer only and no handmixing shall be allowed for CC works.


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NOTE : In case of any contradiction between description of item given inthe bill of quantities(BOQ)/Job Schedule and that given in the

technical specifications, the former i.e. BOQ/Job Schedule shall befollowed.

EARTHWORK:

1. SETTING OUT AND MAKING PROFILE:

Masonry pillars will be erected at suitable points. These bench marks shallbe c onnected to standard bench mark. In addition to these pillars,center line pillars shall also be erec ted by the Contrac tor and footingpositions shall be marked with the help of these pillars. The necessary

profile shall be set out. The level shall be taken at an interval as direc tedby EIC.The levels shall be recorded in field books and plotted on plan beforestarting the excavation.

2. EXCAVATION FOR FOUNDATION:

The cutting shall be done to minimum depths as per drawings and asadvised by EIC. Any excess excavation carried out by the Contractorwithout proper permission from EIC shall not be paid and the excess depthshall be made good by the Contractor by PCC 1:4:8 at contractors own

cost.

BACKFILLING:In case water is encountered during the excavation for foundation, orflooding of pits due to any other reasons the contractor shall arrange fordewatering the same at his own cost.

2.1 EXCAVATION IN HARD ROCK:

CUTTING

Where hard rock is met, generally excavation by chiselling and wedging

shall be carried out. Excavation by blasting shall be done only after takingall safety precautions and approvals as required and after obtainingwritten approvals from Engg.-In-Charge/Architects. In case of excavationby blasting all the provisions of explosive rules 1940 (Correc ted upto date)shall be complied with storing, transportation and handling of explosivematerials. The blasting operation shall be carried out under the supervisionof a responsible authorised agent of the contractor. Blasting work shall not


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be carried out within 200 metres of an existing structure unless otherwisepermitted by the Engg.-In-Charge / Architects.

3.0.0 MATERIALS FOR FILLING

3.1.0 SAND

Sand used for filling shall be clean river sand hard, gritty, dry and coarse,free from earth, silt organic matter, clay and other deleterious materials.

3.2.0 MOORUM or MURRUM:

3.2.1 QUALITY OF MOORUM or MURRUM:

The moorum shall be naturally occurring material formed by disintegrationof rock. It shall be free from vegetation, rubbish or materials of organicorigin and scales deleterious to concrete and reinforced concrete.

Pieces of hard rock which do not get crushed under the roller shall notexceed 50mm size.

3.2.2 FILLING:

Filling shall be done in 15 cm thick layers and every layer shall be powerrolled with 8/10 ton roller so as to achieve maximum compaction and tillsuch time that no further movement is observed under the wheels of theroller. Hand rolling is permissible in case filling is done inside sales building.

After filling is completed the modified Proctor Density shall be 92% withOMC.

Before start of work the contractor shall supply the samples of murrumfrom each quarry to cover the variations expec ted in the supply. Thesamples shall be tested for the following in a recognised laboratory inaccordance with IS:2720 for the following.

Silt and clay content.Moisture-content and dry density relationship at modified Proc ter density.


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Moisture Control: Water shall be always sprayed and not poured.Ponding shall never be allowed. In wet weather the work may have to be

carried out by using suitable safeguards without any extra cost. Care shallbe taken to see that moisture is uniformly spread throughout the layer andwhere necessary mixing with harrows and rakes shall be done.

Measurements: Measurements shall be of the cubic contents of thecompleted filing and shall be determined by taking level of testing groundand after final layer for each type of filing. All dimensions are forcompacted thickness.

4.0.0 CEMENT

Unless otherwise specified ordinary Portland cement of 43 gradeconforming to IS:8112 shall be used for all concrete works. However, OPCgrade 53/ Portland Pozzolana Cement (PPC) may be used after approvalof EIC.

4.1.0 SUPPLY:Cement used shall be one of the following with prior approval of theEngg.-In-Charge/ consultant / architect.

a. Grade 33 Ordinary Portland cement conforming to IS:269b. Grade 43 Ordinary Portland Cement conforming to IS:8112.c. Grade 53 Ordinary Portland Cement conforming to IS:12269.Portland Slag Cement conforming to IS:455.

Portland Pozzolana Cement conforming to IS:1489.

Cement to be used shall be of the best quality from reputed brands likeAC C/ Birla/Gujrat Ambuja/L&T /Lafarge /Grasim or any other equivalentas approved by the C lient / consultant.

Where specified, special cement like Sulphate resisting Portland cement(conforming to IS:8042-E), Coloured cement shall be used.

Rapid hardening cement shall have strength in one day equal to that ofOPC in 3 days. It shall be used for products like Hume pipe, tiles, sleepers,


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poles, pre stressed and prec ast members. It shall also be used forfoundation, bridges, culverts, causeways, etc. where quick construction

activity is required however with prior permission of theconsultant/architect. Test certificates showing that the cement complieswith the specifications must be submitted to the EIC /consultant.

Sulphate resistant cement should possess low heat of hydration, morecompressive strength at 3, 7 and 28 days than OPC. It should be capableof withstanding attack of aggressive substances like sulphate of sodium,magnesium, calcium, etc. which damage concrete structures. It shall beused with prior approval for structures in or near sea water, where the soilconditions are aggressive, where repeated cycles of drying and wettingoccur and also for structures exposed to sulphate attack like industrial

drains, sewage pipes, foundations, bridges, dams, tunnels. Test certificatesshowing that the cement complies with the specifications must besubmitted to the EIC/consultant.

Coloured cement shall be white or grey Portland cement mixed withpigment as specified in the item of work. It shall comply with physicalrequirements of IS:269/8112 and pigments shall be inorganic oxidepigments either natural or synthetic in origin complying with therequirements of B.S.:1014. The pigments used for coloured cements shallbe of approved quality and its quantity shall not exceed 10% of cement

used in the mix. The mixture of pigment and cement shall be properlyground to have a uniform colour and shade. The pigments shall have suchproperties as to provide durability under exposure to sunlight andweather. The pigment shall have the property such that it is neitheraffec ted by the cement nor detrimental to it.

In case more than one type of cement is used in any work, a record shallbe kept showing the location and type of cement used. Each type ofcement shall preferably be obtained from one constant sourcethroughout the contract. Cement of different types shall not be mixedwith one another. Different brands of cement or the same brand ofcement from different sources shall not be used without prior notificationor approval by client.

The cement shall be supplied to the site in original sealed bags, whichshall be labeled with the weight, name of manufacturer, date ofmanufacture, brand and type. Cement received in torn bags shall not be


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used. Bags of cement that vary in weight by more than 3% shall not beaccepted.

The contractor shall maintain a daily record of cement received andconsumed in an approved form and a copy shall be submitted to theEngg.-In-Charge once a week.

4.2.0 Storage:

4.2.1 Cement bags shall be stored dry, leak proof, moisture proof andwell-ventilated godowns built at the cost of the contractor. Cement ofdifferent types shall be stored in separate godowns or separatecompartments of a godown.

The floor of the godown shall be raised and shall consist of wooden planksresting on the base prepared with dry bricks laid on edges. Stacking ofcement bags shall have a c learance 150 to 200 mm above the floor and450 mm from the wall.

Cement shall be stored in stacks, which are not higher than 10 bags toavoid lumping due to pressure and in such a manner as to permit easyaccess for inspection and identification.

The bags shall be kept close together in rows of two bags to reducecirculation of air as much as possible. The bags shall be arranged inheader and stretcher fashion so as to lessen the danger of topping.

4.2.2 First in, First out rules shall be applied while removing the bags foruse.

4.2.3 Cement stored during monsoons or for an unusually long period,shall be completely enclosed in polythene sheet which shall cover the topof the stack. The contractor shall ensure that the polythene sheet is notdamaged at any time during use. Storage under tarpaulins shall not bepermitted.

4.2.4 No stored cement bag shall be used after three months from thedate of manufacture. Generally, stacking and storing of cement shall bein accordance with Clause 3.2 of IS:4082.


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4.3.0 Quality of cement.

4.3.1 The manufacturer shall satisfy himself that the cement conforms tothe relevant Indian standards and if required, shall furnish a certificate tothis effec t to the purchaser or his representative within ten days of thedespatch of the cement.

4.3.2 The contractor shall be fully responsible for the quality of cementbrought to work site. In case the contractor has any doubt regarding thequality of cement brought to work site, it is upto him to have it tested at hisown expense and make sure that the cement is of acceptable quality.

4.4.0 Testing:

4.4.1 The contractor shall submit test certificates furnished by themanufacturer to client/consult. Where the client/consultant is notconvinced about the quality of cement, he can ask the contractor tohave the cement tested or he can take samples in the presence ofcontractor from cement bags stored at work site and forward them togovernment approved laboratory for testing. Expenses towards such testsshall be borne by the contractor.

4.5.0 Sampling:

4.5.1 For one lot of 50 ton of cement, 2% of bags shall be picked out atrandom, from which one sample of 15 kg shall be taken.

4.5.2 Samples for testing may be taken by the purchaser or hisrepresentative within one week of delivery and all tests shall becommenced within one week of sampling.

4.5.3 When it is not possible to test the samples within one week, thesamples shall be backed and stored in airtight containers till testing.

4.6.0 Causes for rejection:

4.6.1 Cement not conforming to relevant specification shall be rejec tedby the client/consultant. The contractor, at his own expense shallimmediately remove rejected cement from the work site.


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4.6.2 Damaged or reclaimed or partly set cement will not be permitted to

be used and shall be removed from the site.

4.6.3 The minimum requirements for any type of cement to beconsidered as acceptable are tabulated in Table-A.

TABLE A : PHYSICAL REQUIREMENTS FOR CEMENT.

Type of cement OPC33

Grade

OPC 43Grade

OPC 53Grade

PPC PSC

Code NO. IS:269 IS:8112 IS

12269IS 1489 IS

455

Fineness by Blainesmethod (sq.m/kg),min.

225 225 225 300 225

Setting time (mins)Initial(More than)Final (Less than)

30600

30600

30600

30600

30600

Loss on ignition (Max %) 5 5 4 5 4

Insoluble Residue (Max %) 4 2 2 0.96X+4}X=% ofPozzolana

2.5

Soundness (Max)Lechatelier (mm)Autoclave (%)

100.8

100.8

100.8

100.8

100.8

Compressive Strength*(Min) (N/sq.mm)7 days28 days

2233

3343

3753

2231

22--

Compressive strength test shall be carried out on 70.70x70.70x70.70mm mortar cubes made from cement and sand (conforming to IS

650) mixed in the proportion of 1:3.0

4.7 WORKMASNSHIP

The use of bulk cement will be permitted only with the approval of EIC.Changing of brands or type of cement within the same structure will notbe permitted.


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CONTRACTOR will have to make his own arrangements for the storage of

adequate quantity of cement. Cement bags shall be stored in a dryenclosed shed (storage under tarpaulin will not be permitted), well awayfrom the outer walls and insulated from the floor to avoid c ontact withmoisture from ground and so arranged as to provide ready access.Damaged or reclaimed or partly set cement will not be permitted to beused and shall be removed from the site. Not more than 12 bags shall bestacked in any tier. The storage arrangement shall be approved byengineer. Consignment of cement shall be stored as received and shallbe consumed in the order of their receipt at site.

Cement held in storage for a period of Ninety (90) days or longer shall be

tested. Should at any time Engineer have reasons to consider that anycement is defec tive, then irrespective of its origin, date of manufac tureand/or manufac turers test certificate, such cement shall be testedimmediately at Contractors cost. It shall not be used in any work unlessconfirmed by approved lab after testing. Contrac tor shall not be entitledto any claim of any nature on this account.

5.0.0 AGGREGATES

Aggregates for concrete shall be procured from approved sources

conforming to the spec ifications of IS:383 and shall be chemically inert,clean, strong, durable, with limited porosity and free from deleteriousmaterials which cause corrosion of reinforcement or may impair thestrength and durability of concrete. Aggregates shall not contain water-soluble sulphur trioxide in excess of 0.1%. The chloride ion content of fineand coarse aggregate shall not exceed .06% and 0.02% respectively bymass of dry aggregate. If either aggregate exceeds these limits thematerial may still be considered acceptable by the engineer providedthat the total chloride ion concentration derived from the aggregate isnot grater than 0.35% by mass of the cement in the mix.

All aggregates shall comply with IS:2386 and IS:383 in respect of impuritiesand additionally with the following :

(a) Absorption6% maximum by weight for ordinary construction and 2% maximum forwater proof construction.


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(b) Salt

1% maximum (equivalent anhydrous calcium percentage by weight ofcement)

(c) Carbonates10% maximum by weight.

Unless otherwise specified, fine aggregate shall imply natural river sand forthe purpose of reinforced concrete work. However, stone dust confirmingto IS 2386 may be allowed by EIC to be used under exceptional cases.

5.1.0 FINE AGGREGATE:

5.1.1 GENERAL REQUIREMENTS:

a. The maximum size of the sand particles shall be 4.75 mm and downgraded.

b. The sand shall be free from adherent coatings and shall not containharmful materials such as iron pyrites, coal, mica, slit, clay, alkali, seashell, organic impurities, loam, etc ..

c. The maximum quantity of deleterious materials shall not exceed 5percent and the limits specified in table 1 of IS:383 when tested in

accordance with IS:2386 (Part-2).d. Aggregates, which are chemically reactive with alkalis of cement, shall

not be used, as it will induce c racking of concrete.e. Silt and dust present in natural sand shall be limited to 8% by weight. In

case it is more than 8%, it shall be washed at site with clean water.Presence of mica shall not be more than 1% by weight.

5.1.2 Grading:

Fine aggregate with a fineness modulus value less than 2 shall not beused for reinforced concrete work. The natural sand used for RCC workshall have a grading conforming to one of the three grading zones givenin the following table (Table B). Fine aggregate conforming to grade IV asper IS:383 shall not be used for RCC works.


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For coarse sand the grading of sand as determined by the methodprescribed in IS : 2386 Part I shall be within the limits of grading III given in

Table B.

Stone dust shall be obtained by crushing hard stone and the grading shallbe as determined by the method prescribed in IS:2386 Part I & II. It shall bewithin the limits of grading zone III. The fineness modulus of stone dust shallnot be less than 1.8. It shall not contain more than 8% of silt as determinedby field test with measured cylinder. The silt content is found out bykeeping a sample of stone dust without drying in 200 mm measuringcylinder. The quantity of the sample shall be such that it fills the cylinderupto 10mm mark. Then clean water shall be added upto 150 mm mark.The mixture shall be stirred vigorously and the contents allowed to settle

for 3 hours. The height of slit visible as settled layer above the stone dustshall be expressed as percentage of the height of the stone dust below.The stone dust containing more than 8% of silt shall be washed so as tobring down the content within the allowable limit.

When grading falls outside the limits of any particular grading zone ofsieves, other than 600 micron IS sieve, by a total amount not exceeding5%, it shall be regarded as falling within that grading zone.

TABLE B: GRADING OF FINE AGGREGATE (AS PER IS :383)

IS SieveDesignation

Pecentageby wightpassing ISSieve

Grading ZoneI

Grading ZoneII

Grading ZoneII

Grading zoneIV

10 mm 100 100 100 100

4.75 mm 90-100 90-100 90-100 95-100

2.36 mm 60-95 75-100 85-100 95-100

1.18 mm 30-70 55-90 75-100 90-100600 micron 15-34 35-59 60-79 80-100

300 micron 5-20 8-30 12-40 15-50

150 micron 0-10 0-10 0-10 0-15


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5.1.3 Sampling and testing:

a.

Fine aggregate shall be subjected to inspection and testing.b. The method of sampling for test shall be in accordance with IS:2430.c. Samples of fine aggregates for testing shall be collected from

transportation units or stack or stockpiles. Each sample shall be packedseparately and despatched to the testing laboratory.

d. Packing and marking of samples shall be done in accordance withclause 6.0 of IS:2430.

e. The contractor shall furnish test results of samples as may be requiredby the client/consultant.

f. Testing shall be carried out in accordance with IS:2386 (Parts-1 to 8).5.1.4 Storage:

a. Aggregate shall be stored on a hard surface or a well designedplatform of concrete, timber, metal or any other approved material soas to prevent the mixture of clay, dust, vegetable and other foreignmatter.

b. Storing and stacking of fine aggregate shall be done in accordancewith clause 3.5 of IS:4082.

c. While stacking, the aggregate shall not form pyramids resulting insegregation of different size particles. The stacks shall be regular.

d. Unless otherwise specified or necessitated by site conditions, stackingof fine aggregate shall be suffic iently away from that of coarseaggregate.

Coarse aggregate shall mean aggregate of which not less than 95% byweight is retained on 4.75 mm mesh IS test sieve of IS:2430 and shallconform to IS:383.

5.2.0 COARSE AGGREGATE:

5.2.1 General Requirements:

Coarse aggregates shall be machine-crushed stone of black trap orequivalent black hard stone and shall be hard, strong, dense, durable,clean or procured from quarries approved by the client/consultant.


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Generally coarse aggregate shall be cubical in shape and not flake orelongated.

Aggregates shall be free from injurious amounts of disintegrated pieces,reactive silica, alkali, harmful salt, organic matters and other deleteriousmaterials. Coarse aggregates to be used for reinforced c ement concretework shall not contain any material liable to attack the steelreinforcement.

The maximum quantity of deleterious materials shall not exceed 5 percentof the weight of coarse aggregate and the limits specified in Table I ofIS:383 when tested in accordance with IS:2386 (Part-2).

The amount of fine partic les occurring in the free state or as looseadherent shall not exceed 1% when determined by laboratorysedimentation tests as per IS:2386.

In selec ting the aggregates the Contrac tor shall satisfy and ensure thatthe source is suitable for regular supply and a watch shall be maintainedthat the particle shape and grading remain reasonably uniformthroughout the progress of work.

The contractor shall arrange to supply coarse aggregates in single size, for

each nominal size, conforming to the grading given in Table 2 of IS:383.The single sizes shall be combined in suitable proportion to get desiredoverall grading of aggregates. The c lient/consultant at his discretion, mayallow the use of Graded Aggregate of nominal size, to conform to thegrading spec ified in Table 2 of IS:383.

5.2.2 Maximum Size:

The maximum size of aggregates shall not be great than one quarter ofthe maximum thickness of the member so as to surround all reinforcement.For heavily reinforced concrete members, the nominal size of aggregateshall be 5 mm less than the minimum clear distance between thereinforcement main bar or 5 mm less than the minimum cover to thereinforcement whichever is smaller.

In reinforced concrete work, unless otherwise specified, nominal maximumsize of coarse aggregate shall be 20 mm and down.


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5.2.3 Storage:

a. Generally, storage of coarse aggregate shall conform to clause 3.5 ofIS:4082. Aggregates shall be stored at site on a hard and dry patch ofground, preferably leveled and rolled.

b. Aggregates of various sizes shall be stored in separate stockpiles withheight not exceeding 1m to prevent coning or segregation. A bottomlayer of coarse aggregate 100 mm deep shall be undisturbed whileremoving the material for use.

c. If the aggregates are stored at site for a long time, it shall be sievedbefore use, to remove dust, if direc ted by the consultant.

6 . CONCRETE WORK

MATERIALS FOR STANDARD CONCRETE:The ingredients to be used in the manufac ture of standard concrete shallconsist solely of a standard type portland cement, clean sand, naturalcoarse aggregate, clean water and admixtures.

CONSISTENCY:

The consistency of the concrete shall be such that it flows sluggish into theforms and around the reinforcement without any segregation coarseaggregate from mortar. The slump tests are mandatory and shall becarried out at regular intervals so that the consistency concrete can bemonitored.

PLACING OF CONCRETE:Concreting shall commence only after inspection and approval by EIC.Shuttering shall be clean and free from deposits of foreign materials andproper de-shuttering agent shall be applied to the surface. Properarrangements shall be provided for conveying the concrete at the placeof deposition without disturbing the reinforcement.


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COMPACTION:Concrete shall be compac ted immediately after placing by means of

mechanical vibrators. All RCC works shall be cured for a minimum periodof 14 days or more as advised by EIC.

INSPECTION AND RECTIFICATION OF DEFECTS:

Immediately on removal of forms, the RCC works shall be examined by

the Engg.-In-Charge / Architects before any defects are made good.

The work that has sagged or contains honey combing to an extent

detrimental to the structural safety or architec tural concept shall be

rejected.

Surface defects on a minor nature may be accepted and the same shall

be rec tified as follows:

(a) Bulges due to movement of forms, ridges at forms, ridges at form joints

shall be carefully chipped and then rubbed with a grinding stone.

(b) Honeycombed and other defective areas must be chipped out, the

edges being out as straight as possible and perpendicular to the

surface. Shallow patches are first treated with a c oat of thin grout (1

cement : 1 sand) and then filled with mortar similar to that used inconcrete. Large and deep patches shall be filled up with concrete

held in place by forms and shall be reinforced.

(c) Holes left by bolts shall be filled carefully with mortar. Holes extending

right through the concrete shall be filled with mortar with a pressure

gun.

(d) The same amount of care to cure the material in patches should be

taken as with the whole structure.


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POST TREATMENT OF SURFACE:

The surface which has to receive plaster or where it has to be joined with

brick masonry walls shall be properly roughened immediately after the

shuttering is removed.

ACCEPTANCE CRITERIA OF CONCRETE WORK:

Minimum of six sample cubes shall be taken for all concreting work

(periodicity a. Once for minimum 5 cum or part thereof, b. Minimum 15

cum or part thereon) and three cubes shall be tested after 7 days curing

and balance after 28 days curing.

7 Days Test:

The average strength of the three spec imens shall be accepted as thecompressive strength of the concrete provided that the difference

between maximum and minimum strength of the three cubes does not

exceed 15% of average strength

In case the 7 days strength is not satisfactory all further work structurally

interlinked with the concrete represented by the samples shall be stopped

till the remaining three cubes are tested for 28 days strength and are

found satisfac tory.

28 Days Test :

The tests should generally be carried out on 28th day, but in no case,

should be delayed beyond 35 days. The strength of the cubes shall be as

specified in table above if they are tested on the 28th day. In case, the

cubes are tested after 28 days, the minimum acceptable compressive

strength shall be increased by 1.5 kg/cm2 for each day beyond 28th day.

The acceptance criteria of 28 days test shall be as follows:

(a) If the average compressive strength of three cubes is more or equal tothe comp. Strength shown in table above, the concrete shall be

accepted at full rates.

(b) If the average comp. Strength of the three cubes is less than specified

but not less than 75% of the specified strength, the concrete shall be

accepted at reduced rates at the discretion of EIC. The reduced rate


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shall be calculated on proportionate basis, i.e. for every percent

decrease in the specified strength the rate shall be reduced by the

same percentage.

(c) If the average compressive strength of the three cubes is less than 75%

of the spec ified strength, EIC shall either rejec t the defective portion or

get it dismantled along with the structurally connected work as

considered necessary at the risk and cost of the contrac tor. EIC may

also desire to carry out additional tests on the defective work and if on

the basis of these additional tests, EIC is satisfied about the structural

adequacy of the concrete the concrete work may be accepted at

the reduced rate as specified in b) above except, for the reducedstrength below 75% for which the reduction shall be 1.5 times for every

percent decrease below 75%

Example: Average compressive strength is 70% of specified strength. The

rate payable shall be 75 1.5x(75-70) = 67.5% of tendered rate.

MEASUREMENT

All measurements shall be as per IS:1200.

7.0.0 STEEL REINFORCEMENT:

7.1.0 Supply:

Steel reinforcement for concrete shall be round/ribbed bars, unlessotherwise spec ified and shall comply with the following grades.

(i)High strength deformed steel bars (ii) TMT bars conforming to IS:1786. Ifspec ified, tested quality high yield strength deformed corrosion resistantsteel (CRS) bars from TATA (TISCON-50CRS), SAIL (HCR-REBARS Gr.M) orequivalent conforming to IS:1786 for mechanical properties with improved

corrosion resistance and bond strength shall be used.

Only new steel shall be delivered to the site and shall be free of mill scale,loose rust, grease oil, paint or any other deleterious materials whichreduce or destroys bond.


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The chemistry of CRS should be as given below:

Carbon -0.15% maxSulphur (S) -0.05% maxPhosphorus (P) -0.12% maxS+P -0.17 % maxSilicon -0.45 % maxCorrosionResistant elements -1.5 % max

7.5.0 Binding Wire:

The reinforcement shall be securely bound wherever bars intersect or

wherever required with 18 gauge (1.22 mm) annealed steel wireconforming to IS:280.

7.6.0 Chairs:

Adequate no. of chairs shall be provided to prevent sagging ofreinforcement during conc reting.

7.7.0 Mechanical splices:

Mechanical connections for splic ing reinforcement bars in congestedlocations shall be used only with the approval of consultant/Engg.-In-Charge. Patented couplers as manufactured by Usha Martin IndustriesLtd. (CCL bar grips) and BBR India Ltd. (BBR SWIF) shall be used wherevermentioned in the drawings. The couplers shall be attached to thereinforcement bars by forging, hydraulic pressing or screw couplers inspec ial c ircumstances may be permitted. All operations relating toreinforcement coupling shall be done using suppliers patented machine /equipment and in the presence of the suppliers representative. Thecontractor shall submit relevant trade literature, mil certificates, certificateof origin and letters of approval for each proposed application. A sampleof each type of mechanical coupler shall be submitted for testing andapproval prior to the use of any coupler in the works.


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7.8.0 Welding electrodes:

Electrodes used for welding of steel bars shall be ordinary mild steel grade2 electrodes conforming to IS:814 and shall be the best quality andapproved by the Engg.-In-Charge. The work shall be carried out strictly asper IS:2751 and IS:9417.

7.9.0 Causes of Rejection:

Steel reinforcement, not conforming to relevant specification, shall berejected by the c lient/consultant. Every bar shall be inspected beforeassembling on the work and defective, brittle or burnt bar shall berejected. Cracked ends of bars shall be discarded. The contractor at his

own expense shall immediately remove rejected steel from the work site.

7.10.0 Storage:

Steel reinforcement shall be handled and stored in a manner thatbending or distortion of the bars is avoided and corrosion of steel isprevented. They shall be stored in such a manner that they are not indirect contac t with the ground (at least 150 mm clear above ground). Incase of long storage, a coat of cement wash shall be given to thereinforcing steel to prevent any scaling or rusting. Any reinforcement,

which is certified as corroded by the Engg.-In-Charge, shall either beimmediately withdrawn from site or stand blasted and coated withcement slurry. No extra payment shall be made for sand blasting andcement coating. Bars of d ifferent c lassifications and size shall be storedseparately. Generally, storage of reinforcements shall be in accordancewith clause 3.7 of IS:4032.

8.0.0 WATER :

Water used for various works shall conform to IS:456.


Water used for both mixing and curing of concrete/brickwork/plaster aswell as for washing aggregate shall be potable and free from injuriousamounts of deleterious materials like alkalis, acids, oils salts, sugar, organicmaterials, vegetable growth or other substances which are likely to affect


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the strength or durability of concrete and other construction materials.Before starting any conc reting/brickwork/ plaster work and wherever the

source of water changes, the water shall be tested for its acceptability foruse in concrete etc. by the methods given in IS:3025. No water shall beused until tested and found satisfac tory and cost of all such tests shall beborne by the contrac tor.

Hard and bitter water shall generally be found unsuitable for curing mortarand concrete.

Water for use in mixing with cement shall neither be hotter than 25C norcolder than 5 C at the time of mixing.

Whenever temperature controlled concrete is specified, the contractormay establish an ice making plant of required capac ity at site.

Water used for curing shall not produce any objectionable stain orunsightly deposit on the surface. It shall be free of elements thatsignificantly affect the hydration reaction. Presence of tannic acid or ironcompounds in water is objec tionable.

Acceptance Criteria:

Water to be used, shall satisfy the following:

8.2.1 To neutralise 100 ml sample of water, using phenolphthalein as anindicator, it should not require more than 5 ml of 0.02 normal NaOH.

To neutralise 100 ml sample of water, using mixed indicator, it should notrequire more than 25 ml of 0.02 normal H2SO4

8.2.3 It should not contain solids by weight in excess of the following:

Organic 200 mg/ litreInorganic 3000 mg/litreSulphates 400 mg/litreChlorides 500 mg/ litre for reinforced concrete work and

2000 mg/litre for other worksSuspended 2000 mg/litreMatter


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The pH value of water shall be between 6 and 8.

If required by the Engg.-In-Charge it shall be tested by comparison withdistilled water. Comparison shall be made by means of standard cementtests for soundness, time of setting and mortar strength as spec ified inIS:269. Any indication of change in time of setting by 30 minutes or more ordecrease of more than 10% in strength of mortar prepared with watersample when compared with the results obtained with mortar preparedwith distilled water shall be sufficient cause for rejection of water undertest.

8.3.0 Sample for Testing:

The sample of water taken for testing shall represent the water proposedto be used, with due account being paid to seasonal variation. Thesamples shall not receive any treatment before testing other than thatenvisaged in the regular supply of water proposed for use. The sampleshall be stored in a clean container. Test shall be carried out only once forone particular source.

Testing shall be done as per IS:3025 (Relevant parts).

8.4.0 Storage:

Storage of water shall generally conform to IS:4082, whenever water is tobe stored for construction purposes. Water storage tanks shall be coveredto the satisfaction of the Engg.-In-Charge to prevent contamination.

9.0.0 ADMIXTURES

Admixtures shall be used in concrete, mortar plaster etc. as specified inthe schedule of items and/or drawing only after the product is approvedby the client/consultant. The contractor is bound to furnish all suchinformation like dosage, method of application, chloride content, etc.required to dec ide on the suitability of the admixture. All required testsshould be carried out at the instructions of the c lient at no extra cost.

Use of admixture being a specialised job, shall be carried out strictly as permanufacturers recommendations.


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Admixtures used shall conform to the following relevant BIS codes andshall be purchased from reputed manufac turers as approved byclient/consultant. In reinforced concrete, the chloride ion of anyadmixture used shall not exceed 2% by weight of the admixture asdetermined in accordance with IS:6925 and the total chloride ion in alladmixtures used in concrete mi shall not exceed 0.83% by weight ofcement. The addition of calcium chloride to concrete containingembedded metal will not be permitted under any circumstance.

Accelerating Admixtures conforming to IS:9103 & 2645. It shall be in liquid

state with a spec ific gravity of 1.3 and complying with ASTM C-494 type E.It shall accelerate the setting and hardening of the concrete mix therebyachieving high early ago strength. It shall be from C ICO or equivalent andused at the rate instructed by the manufacturer. It should be compatiblewith all types of cement.

Retarding Admixtures conforming to IS:9103. It shall be in liquid state with aspec ific gravity of 1.22 and complying with ASTM C-494 type B&D, CRD-C87 type B & D, BS:5075 part 1. It shall be added to the concrete mixduring the mixing process along with water and aggregates. No extension

of normal mixing time is necessary. It shall delay the initial and final settingtime. It shall help to spread the heat of hydration over a longer period oftime. It shall give a highly workable concrete with a low W/C ratio. It shallbe from C ICO, Feb Roffe or equivalent and be used at the rate instructedby the manufacturer, with cement, depending on the amount ofacceleration of hardening required. It should be compatible with all typesof cement.

Air-entraining Admixtures conforming to IS:9103.

Water-reducing admixtures conforming to IS:9103. Only naphthalenebased water-reducing admixture/plastic izers shall be permitted.

Integral waterproofing admixtures conforming to IS:2645. It shall be fromFeb Roffes Roff Hyseal, Roff Hyproof, Algiproof or equivalent. It shall beused as an excellent cement admixture in all types of concrete/ plastermortars, pointing mortars, masonry works, guniting works and pressure


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grouting works. It shall improve resistance of the surface to weatheringand chemical attacks. It shall be no-toxic so as to use for waterproofing in

water tanks, reservoirs, tanks, etc.

9.2.0 Product information:

9.2.1 The contractor shall further provide the following informationconcerning each admixture to the c lient/consultant.

a. Optimum dosage and detrimental effects of under-dosage and over-dosage.

b. Chemical names of the main ingredients in the admixture.c. The chloride ion content expressed as percentage by weight of

admixture.d. Whether or not the admixture leads to entrapment of air when used in

the manufac turers recommended dosage and if so, to what extent.

Where two or more admixtures are proposed to be used in any one mix,the manufacturers written confirmation of their compatibility shall beprovided.

There would be no increase in risk of corrosion of the reinforcement orother embodiments as a result of using the admixture.

9.3.0 Sampling:

9.3.1 Sampling for testing shall be done in accordance with clause 4.1 ofIS:9103 for liquid admixtures and clause 4.2 of IS:9103 for non-liquidadmixtures.

9.3.2 Samples shall be packed in moisture-proof airtight containers.

9.3.3 Sampling of integral waterproofing compound shall be done asgiven in IS:2645.

9.4.0 Testing:

For chec king the physical properties of any admixture, tests shall becarried out as detailed in clause 3 of IS:9103. Results shall conform to therequirements given in Table 1 of IS:9103.


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For air entraining admixture, tests shall be carried out as agreed tobetween the client/consultant andthe manufacturer. Except where

resistance to freezing and thawing and to disruptive action of de-icingsalts is necessary, the air content of freshly mixed concrete in accordancewith the pressure method given in IS:1199 shall not be more than 2% higherthan that of the c orresponding control mix and in any case not more than3% of the test mix.For integral waterproofing compound, tests shall be carried out as permethods given in IS:2645.

Uniformity tests on the admixture are essential to compare qualitativelythe composition of different samples taken from batch to batch or fromthe same batch at different times.

All tests relating to concrete and admixture shall be conductedperiodically at an independent laboratory and compared with the datagiven by the manufac turer.

9.5.0 Storage:

9.5.1 Admixtures shall be stored in moisture-proof, airtight containers.

9.5.2 Storage shall in general conform to IS:4082.

10.0.0 FORMWORK

10.1 General requirements:

10.1.1 Shuttering for conc rete work below ground level shall be of wroughtformwork and that for concrete work in superstructure shall be of fineformwork.

10.1.2 Formwork shall be of Marine Plywood of minimum 12 mm thicknessor steel capable of resisting damage to the contact faces under normalconditions of erecting forms, fixing steel and plac ing concrete. Fordesignated areas prominently in public view the choice of material shallbe decided by the Engg.-In-Charge.

Where plywood is used, it shall be of best quality, resin bonded andwaterproof. Formwork shall be minimum 12mm thick shuttering quality


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(d)They shall give a clear metallic ringing sound when struck by a malletand shall not break when dropped on the ground on their flat face in a

saturated condition from a height of 600 mm.

(e)They shall show a fine-grained, uniform, homogeneous and densetexture on fracture and shall be free from lumps of lime, lamination,cracks, air holes, soluble salts causing efflorescence or any otherdefec t which may impair their strength, durability, appearance andusefulness for the purpose intended. They shall not have any partunder-burnt.

(f)The size of the conventional bricks shall be 225 x 110 x 75 mm. Onlybricks of one standard size shall be used in one work unless specially

permitted by the Client / Consultant. The following tolerances arepermitted in the standard conventional size adopted on the particularwork.

Length plus or minus 3.0 mmBreadth plus or minus 1.5 mmDepth plus or minus 1.5 mm

The size of the modular bricks shall be 190 x 90 x 90 mm or 190 x 40mm.

(g) The crushing strength of the brick to be used in all types of worksshall not be less than 75kg/sq.cm unless otherwise specified whentested according to IS:3495 (Part-1).

(h) After immersion in cold water for 24 hours, absorption by weightshall not exceed 15 percent of the dry weight of the brick whentested according to IS:3495 (Part-2).

(i) Efflorescence in bricks shall be within limits prescribed in (Not morethan 10% of the exposed area of the brick shall be covered with athin deposit of salts) IS:3495 (Part-3).

NOTE: PAYMENT TO BE MADE ON ACTUAL EXECUTED VOLUME OF BRICK

WORK AT SITE.

11.1.2 First Class Bricks for Exposed Brick Work:


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First class bricks are those, which strictly conform to the standard sizeof modular bricks and such that ten layers of brick laid in mortar

shall form masonry of 1 m height. These bricks shall bemanufactured from good quality plastic earth, which is free fromsaline deposits. They shall have straight edges and even surfaces.When immersed in water for an hour they shall not absorb watermore than 1/6thof their weight. On drying they shall not show anysign of efflorescence.

11.1.3 Storage of Bricks:

A) Brick shall not be dumped at site. They shall be stacked in regulartiers of height not exceeding 1.5m.

B) Bricks of different types and classifications shall be stackedseparately. Generally, stacking of bricks shall conform to IS:4082.

11.1.4 Handling:

Bricks shall be unloaded by hand and carefully stacked. These shallnot be thrown to the ground to avoid any damage.

11.1.5 Sampling and Inspection:

Representative samples shall be submitted by the Contrac tor andapproved samples shall be retained by the Client / Consultant forcomparison and future reference.

All bricks shall be inspected at site and shall be subjected to theapproval of the Consultant who may rejec t such consignments asare c onsidered by him to be inferior to the quality specified.

The contrac tor shall provide all labour and plant required for theinspec tion and conduct of such tests as shall be required by theConsultant without additional charges.

Efflorescence test shall be carried out for a sample of 20 bricks froma stock of 20,000 bricks. Water absorption test shall be done for 32bricks out of a stock of 35,000 bricks. Compressive strength test shallbe done on 50 bricks from a stock of 1,00,000 bricks.


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11.1.6 Storage:

Same as that of C oarse aggregate.

12.0.0 SAND

12.1.0 SAND FOR MASONRY MORTAR & OTHER WORKS:


(A) All the requirements, except partic le size grading stated in thesec tion Fine aggregates shall apply to this sand also. The sand

shall consist of natural sand, c rushed stone sand or crushed gravelsand or a combination of any of these.

(B) The partic le size grading of sand in mortar for unreinforced masonrywork shall be within limits specified below, as per IS:2116.

I.S Sieve

Designation IS:460

(Part-1)

Percentage by

weight Passing I.S

Sieve

4.75 mm 1002.36 mm 90-100

1.18 mm 70-100

600 micron 40-100

300 micron 5-70

150 micron 0-15

(C) Clay, fine silt & fine dust in natural sand, crushed gravel or stonesand shall not be exceed 5% by mass when determined inaccordance with IS:2386 (Part-2).

12.1.2 Sampling and Testing:

(A) The method of sampling shall be in accordance with IS:2430.

Any test which the Client / C onsultant finds it necessary to be doneon sand shall be carried out in accordance with relevant parts of


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IS:2386. If further confirmation as to the satisfactory nature of thematerial is required, compressive strength test on cement mortar

cube (1:6) shall be carried out in accordance with IS:2250 using thesupplied material in place of standard sand and the strength valueso obtained shall be compared with that of another mortar cubemade with a sand of acceptable and comparable quality.

Storage:

Same as that of Fine Aggregate.

12.2.0 SAND FOR PLASTER:


(A) Sand used for external, internal wall surfaces and ceiling plastershall conform to IS:1542 and shall be proc ured from approvedsources.

(B) Unless otherwise specified, sand for plaster shall imply natural riversand.

(C) The sand shall be hard, strong, dense, durable, clean and free from

veins, adherent coatings and shall not contain deleterious materialssuch as iron pyrites, coal, lignite, mica, silt, clay, alkali, sea shell,organic impurities, loam or any other harmful materials in suchquantities so as to adversely affect the strength or durability ofplaster.

(D) Presence of clay, fine silt and fine dust in sand shall not be morethan 4$ by weight as stated in clause 3.0 or IS:1542. Organicimpurities shall also be within limits as per Table 1.0 or IS:383.

12.2.2 Grading

(A)The grading of sand for internal wall and ceiling plaster shall bewithin limits specified in the following Table of IS:1542.


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REQUIREMENTS OF GRADING FOR SANDS FOR INTERNAL WALL ANDCEILING PLASTER

Percentage By Weight Passing IS SieveIS Sieve

Designation (Asper IS:460)

Class-A Class-B

240

120

603015

{98-100 for undercoats{ 100 for finishingcoats{80-95 for under coats{95-100 for finishingcoats

30-855-500-10

98-100 for undercoats100 for finishingcoats80-100 for undercoats95-100 for finishingcoats30-955-650-15

(B) The grading of sand for external plaster coat and renderings shallbe within the limits specified in Table B.

REQUIREMENTS FOR GRADING FOR SAND FOR

EXTERNAL PLASTERING AND RENDERINGS.Percentage By Weight Passing IS Sieve

IS Sieve

Designation(As per IS:460)

Class-A Class-B

480 100 100

240 90-100 90-100

120 70-100 70-100

60 40-85 40-95

30 5-50 10-65

15 0-10 0-15

Class A sand shall be used generally for plaster work but where theyare not available, Class B sand may be used after getting theapproval from C lient / Consultant.


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Deviation of about 5% from the spec ified limits in the grading for

fractions passing IS Sieve 120 and 60 only may be allowed subjectto agreement between the Client / Consultant and the supplier.Any other deviation shall be left to the discretion of the Client /Consultant.

12.2.3 Sampling and Testing:

Same as that for masonry mortar.

12.2.4 Storage:

Same as that of Fine aggregate.

13.0.0 STONES

13.1.0 STONES FOR MASONRY:

13.1.1 General requirements:

Generally, the stone to be used shall conform to the requirements ofIS:1597 (Part-1) and shall be of specified variety such as Granite, Trap

stone, Quartz, sandstone or any other type loc ally available good hardstones.

Stones used shall be strong, sound durable, dense, compact, c losegrained, homogeneous, fire resistant and fee from cracks, flaws ordefects, segregation, seams, weathered portions and other structuraldefects or imperfections tending to affect their soundness and strengthand shall be procured from quarries approved by the consultant.

Stones used shall be small enough to be lifted and placed by hand. Thelength of stone shall not exceed three times the height and the breadthon the base shall not be grater than 3/4 of the thickness of wall not lessthan 150mm. The height of stone may be upto 300mm.

Stones shall be free from rounded, worn or weathered surfaces or skin orcoating which prevents the adherence of mortars.


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Stones to be used as headers, quoins, copings, etc . shall comply with therequirements of facing and hearting as may be relevant.

Stones shall be non-porous and when tested in accordance with IS:1124shall show less than 5% water absorption of its dry weight when soaked inwater for 24 hours.

Dressed and worked stones shall strictly follow the recommendeddimensions given in Table 1 of : IS:1127 depending on the purpose of work.

For specific use (e.g. exposure to chemical fume, fire hazard etc.) type ofstone shall strictly conform to the recommendations of Table 2 of IS:1597(Part 1) or as direc ted by the Client/Consultant.

13.1.2 Quoin Stone or Corner Stone:

For random rubble masonry (uncoursed and brought to course), quoinstone shall not be less than 0.03 m3in volume.

For squared rubble (coursed) masonry, the height of the quoin shall besame as the course height and shall not be less than 450mm in anydirection.

13.1.3 Hearting and Backing Stone :

For random rubble masonry (uncoursed and brought to course) thehearting or interior filling of a wall face shall consist of rubble stones notless than 150 mm in any direc tion, carefully laid, hammered down toproper position.

For squared rubble (coursed) masonry the hearting or the interior filling ofthe wall shall consist of flat bedded stone, carefully laid on their properbeds in mortar.

13.1.4 Through stone or Bond Stone:

One through stone shall be provided for every half a square metre offacing, evenly distributed in a staggered pattern.


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They shall have 0.03 sqm in face area and shall have a tailing for the fullwidth of the masonry when the width of masonry is 600 mm or less.

If the masonry wall is over 600 mm thick, a line of headers overlappingeach other by atleast 150mm shall be laid right through the wall from theface to the back.

The length of the interior headers shall not be less than 450mm and theiraverage c ross sectional area shall not be less than 0.025 sqm.

Bond stone shall be distinctly marked on its face during construction forsubsequent verification.

13.1.5 Sampling:

Sampling of stones including quoins and headers to be used in the workshall be got approved by the Client/Consultant before the work is startedand such samples shall be maintained in the site engineers office for anysubsequent inspection.

13.1.6 Testing:

For compressive strength, test pieces shall be made from selec ted

samples in cubical or cylindrical shape. The diameter or lateral dimensionof a test sample shall not be less than 50mm and the ratio of height todiameter or height to lateral dimension shall be 1:2. Compressive strengthand transverse strength test (if required) on stone samples shall be carriedout in the manner specified in IS:1121.

Water absorption test shall be carried out, if direc ted by the consultant, asper IS:1124.

Tests for durability and weathering shall be done, if direc ted by theconsultant, as per IS:1126 and IS:1125 respectively.

The working of stones to the required sizes and their dressing shall becarried out as per IS:1127 and IS:1129.


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14. PLASTERING

14.1 PREPARATION OF SURFACE:

The following surface preparation shall be made for both single anddouble coat plasters. The surface shall then be thoroughly washed withwater, cleaned and kept wet before plastering is commenced.

In case of concrete the surface shall be chipped by chiseling and wirebrushing, cleaning the surface and erecting scaffolding it required.

14.2 CEMENT PLASTER (SINGLE COAT)

APPLICATION:

Plastering in cement mortar (1:4) shall be started from the top and workeddown towards the floor. All holes shall be properly filled in advance of theplastering as the scaffolding is being taken down. To ensure eventhickness and a true surfac e, plaster of about 15 x 15cm shall be firstapplied horizontally and vertically, at 3 metre intervals over the entiresurface to serve as gauges. The surfaces of these gauged areas shall betruly in the plane of the finished plaster surface. The mortar shall then belaid on the wall, between the gauges with trowel. The mortar shall be

applied in a uniform manner slightly more than the specified thickness andbrought to true surface by working a wooden straight edge reachingacross the gauges with small upward and sideways movements at a time.

All corners, arises, angles and junctions shall be truly vertical or horizontalas the case may be and shall be carefully finished. Rounding orchamfering corners, arises, junctions, etc. where required shall be donewithout any extra payment. Such rounding or chamfering shall be carriedout with proper templates to the sizes required.

Horizontal joints in plaster shall not occur on parapet tops and copings asthese invariably lead to leakages. Good quality lime neroo shall beapplied to plastered surface with steel trowel to a thickness slightly morethan specified and rubbed down to give overall thickness of 12mm andpolished to a perfectly smooth and even finish working from top tobottom.


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Curing shall be commenced as soon as the plaster has hardenedsuffic iently. This shall be done by spraying water at regular intervals.

14.3 CEMENT PLASTER (TWO COAT WORK):

The plaster shall be applied in two coats as detailed below:

Apply 12 mm thick coat of CM 1:4 mixed with CICO / ACCO Proof waterproofing compound mixed as per manufacturers specifications as 1stcostleaving the surface rough.

When the plaster has been brought to true surface with a wooden straightedge the surface shall be left rough with 2mm deep furrows shall be

made with a scratching tool to form key for the finishing coat. The surfaceshall be kept wet till the finishing coat is applied.

Apply 2nd coat of 8mm thick of CM 1:4 and finishing the surface byrubbing with sponge till uniform texture is obtained.

The finishing c oat shall be applied after the undercoat has sufficiently setbut not dried and in any case within 48 hours of laying the first coat.

15.0.0 STRUCTURAL STEEL:

All material shall be new and shall conform to their respectivespecifications. The use of equivalent or higher grade or alternativematerials will be considered only in very special cases subject to theapproval of Client/Consultant.


All structural steel sections shall conform to IS:2062 unless otherwisespecified and shall be clearly rolled to proper dimensions and weightsubject to permissible tolerances as per IS:1852.

The finished materials shall be free from cracks, surface flaws, laminationsrough or imperfect edges and all other harmful defects and shall have asmooth finish. The material shall be free from loose mill scale, rust pits orother defects affecting the strength and durability.


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Structural steel work shall be painted by applying two coats of red oxideprimer conforming to relevant IS code and 2 coats of synthetic enamel

paint (Conforming to IS:2933) or aluminium paint (conforming to IS:2339).However, steel shall be galvanised, if so required by the C lient/Consultant.Normal hexagonal nuts and bolts shall conform to IS:3138-1966. Highstrength structural bolts shall conform to IS:3757. Countersunk bolts shallconform to either IS:8352 or IS:8353 depending on the type of bolt. Blackbolts, nuts and screws shall be in accordance with IS:1363 for Blackhexagonal with nuts of 6 to 39mm and black hexagon screw of 6 to 24mmand IS:1364 and IS:1367 for other sizes.

Hot rolled rivet bars shall conform to IS:1148 and high tensile steel rivet barsfor structural purposes shall conform to IS:1149.

Welding electrodes shall conform to IS:814 and approval of weldingprocedure shall be as per IS:823.

Node connectors for space frame shall be Octagonal or Spherical inshape. It shall a minimum tensile strength as specified in the Bills ofQuantities. Minimum elongation shall be 7% and hardness 170-240 BHN.The nodes machined out of solid bars shall conform to IS:2062 and thecasing shall be as per IS:1030.

The following variety of steel shall be used for structural purpose:

ST-42S: It shall be used for all types of structures (riveted and bolted)including those subjected to dynamic loading and where fatigue, widefluctuations of stresses, reversal of stresses and great restraint are involved.It shall be suitable for welded structures provided that the thickness of thematerial does not exceed 20mm.

ST-42W: Fusion welding quality steel, conforming to IS:2062 shall be usedfor structures subject to dynamic loading where welding is employed forfabrication and where fatigue, wide fluctuation of stresses, reversal ofstresses and great restraints are involved.

Structural steel tubes (ERW) used for building construction shall be hotfinished tubes conforming to IS:1161/IS:1239/IS:806. Tubes shall bedesignated by their nominal bore and shall be classified as light, medium


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and heavy as per IS:1161. Tubes of thickness lower than light tubes shallnot be permitted.

Unless mentioned otherwise, fusion welding quality steel ST-42w shall beused for all the structural steel works and tubes shall be YST 21 conformingto IS:806.

The chemical and mechanical properties for structural steel shall be asstated below:

CHEMICAL COMPOSITION OF STEEL

Steel designation Maximum percentage

Corbon Sulphar Phosphorous

S -42W 0.23 0.06 0.06

S -42S 0.25/0.28 0.06 0.06

ST-42O 0.07

MECHANICAL PROPERTIES OF STEEL

SteelType

Class of SteelProduct

Nominalthickness/ dia

mm

Tensilestrength

kg/mm2

Yield stress

min. kg/mm2% elongation

ST-42-W

(Fusionweldingquality&

ST-42-S(Standar

d quality)

Plate sections (For

example, angles,tees, beams,channels etc.) Andflats

Below 6 mm only

bend test shallbe required.6 mm and upto20 mm Over 20

upto 40 mm

Over 40 mm

42 to 54

42 to 54

42 to 54

26

24

23

23

23

23

Bars (round,square andHexagonal)

Below 10 onlybend test shallbe required.Over 10 mmupto 20 mmOver 20 mm

42 to 54

42 to 54

26

24

23

23


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ST-42-O(Ordinar

yquality)

Plate sec tions (forexample angles,

tees, beams,channels, etc.)and flats

Below 6 onlybend test shall

be required.

6mm andabove

42 to 54 26 23

Bars (round,square andHexagonal)

Below 10mmonly bend testshall berequired.10 mm andabove

42 to 54 26 23

15.2.0 Test certificate:

7.2.1 When the steel is supplied by the Contrac tor, test certificate of themanufacturer shall be obtained according to IS:2062 and other relevantIndian Standards. Notwithstanding the manufacturers certificates, theConsultant/architect may ask for testing of material in approved testlaboratory. The test results shall satisfy the requirements of the relevantIndian Standards. Whenever quality certificates are missing or incompleteor where material quality differs from standard specifications, the

Contrac tor shall conduct all appropriate tests as direc ted by theconsultant/architect at his own cost. Materials for which test certificatesare not available or for which test results do not comply with relevant ISstandard shall not be used.

15.3.0 Storage:

Storage of structural steel shall be as per IS:4082. Steel materials suppliedby contractor shall be marked for identification and each lot shall beaccompanied by manufacturers quality certificate, conforming to

chemical and mechanical characteristics as per relevant IS codes. Allsteel furnished by suppliers shall be checked, sorted out, straightened andarranged by grade and quantities in stores.

Welding wire and electrodes shall be stored separately by qualities andlots inside a dry and enclosed room in compliance with IS:816 and as


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The bottom surface and sides (upto 300mm) shall be treated with

chemical at the rate of 5 litre/sqm(square metre).

The portion of the column foundations and the retaining walls coming in

contact with the backfill, the structure shall be treated at the rate of 15

litres/sqm of the vertical surface. If water is used for ramming the earth fill

then treatment shall be carried out after the ramming operation is

completed by rodding the earth at 150mm c/c close to the structure

surface and spraying the required quantity of chemical. For RCC framed

structures using 1:2:4 or richer concrete the treatment shall start from a

depth of 500 mm below ground level and there is no need to start the

treatment from the bottom of excavation for columns and plinth beams.The earth from 500mm below the ground level and above shall be

treated as described in previous paragraph. However, for RCC frame

structure, there shall be no chemical treatment for column foundations.

Treatment of top Surface of Plinth Filling:

The top surface of filled earth within plinth walls shall be treated with

chemical emulsion at the rate of 5 litre/ sqm before the subgrade of floor is

laid. Holes upto 50-70mm deep at 150mm centres shall be made to

facilitate saturation of the soil with chemical emulsion.

Treatment of Junction of Wall and Floor:

To achieve continuity of vertical chemical barrier on inner wall surfaces,

small channels of 30 x 30mm shall be made at all the junctions before

laying the subgrade and rod holes shall be made upto ground level at

150mm centres and chemical emulsion shall be poured at 15 litre/ sqm of

the vertical surface.

Treatment of soil along external perimeter of Buildings:

After the building is complete, rod holes shall be made along external

perimeter at 150 mm centres and 300mm deep and these holes shall befilled with chemical emulsion at 5 litre/ running metre of perimeter.

16.6 RECORD OF CHEMICAL USED:

A detail record of quantity of chemical used for each operation shall be

kept at site duly approved by Engg.-In-Charge/Architec ts.


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16.7 GUARANTEE

The contractor shall give a guarantee of 10 years for effective anti-termite

treatment barrier.

16.8 MEASUREMENT:

The measurement shall be made in square metres on the basis of the

plinth area of the building at plinth level only for all operations described

above. Nothing extra shall be measured.

17.0.0 Tiles:

17.1.0 Terrazzo Tiles:

Terrazzo tiles shall generally conform to the standards prescribed in IS:1237in all respects.

17.1.1General requirements:(a)All tiles to be used shall be heavy duty flooring tiles only, conforming to

clause 3 of IS:1237.

(b)Tiles shall be manufac tured from cement, natural aggregate andcolouring pigment (where required) as specified in clause 4 of IS:1237,under hydraulic pressure not less than 140 kg/sqcm and shall be giventhe first grinding with machine before delivery to site.

(c)Manufac turing process of tiles shall conform to the requirement givenin clause 5 of IS;1237.

(d)Unless otherwise stated, the size of terrazzo flooring tiles shall be asfollows :

Length (mm) Breadth (mm) Thickness (mm)

200250300

200250300

202225

However, special shapes and sizes of tiles can be asked for by theclient. In such a case, the manufac turer/supplier shall ensure to supplythe tiles only in the specified shape and size.


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(e) Tolerances on length or breadth of tiles shall be +/- 1 mm. In addition,

the difference in length of side between the longest side and shorterside in the sample shall not exceed 1mm. Tolerance on thickness shallbe +/- 5 mm. In addition, the difference in thickness between thethickest and the thinnest tile in the sample shall not exceed 3 mm.

(f) The minimum thickness of wearing layer for the various classes ofterrazzo flooring tiles shall be as specified in Table 1 to IS:1237. Unlessotherwise specified, the tiles shall be supplied with initial grinding andgrouting of the wearing layer.

(g) The wearing layer of the tiles shall be free from projec tions,

depressions, cracks, holes, cavities and other blemishes.

17.1.2 Physical requirements:

The tests on tiles to check physical requirements shall not be carried outearlier than 28 days from the date of manufacture.

(a) Client can ask for any physical test to verify the acceptability of thetiles. All physical tests shall be carried out as per Appendix A to F ofIS:1237 as applicable, depending on the tests to be done.

(b) On testing, the physical requirements shall conform to theacceptability limits spec ified in clause 11 of IS:1237. Tiles, failing tomeet acceptability criteria, shall be rejec ted.

17.1.3 Sampling:

Sampling and inspection shall be carried out as per clause 14 of IS;1237.

17.1.4 Marking:

All tiles shall be legibly marked on the back with the name of themanufacturer or his trade mark. Heavy duty tiles shall be marked H

17.2.0 Ceramic Tiles :

Ceramic tiles to be used for flooring and dado shall conform to IS:13712.These shall be procured from approved manufac turers and a few


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17.2.2 Sampling & Testing :

Sampling shall be done as per IS:13711 and testing shall be done as perIS:13630. Samples of each type/design/finish/print/size/colour of tiles shallbe submitted well in advance to the Architect/consultant for approval atthe contractors cost. The consultant/architect shall retain approvedsample. Tiles shall be procured from a single approved source who canprovide products of consistent quality and physical properties.

17.2.3 Storage :

The tiles shall be delivered in original containers with seals unbroken.Adequate precaution shall be taken to prevent accidental damage totiles while unloading and these shall be stored under cover in mannerapproved by the Engg.-In-Charge.

17.2.4 Acceptance criteria :

Acceptance c riteria shall be as per IS:13711.

17.3.0 Anti-skid tiles :


The tiles shall be free from any flaw, fissure, crack or any othermanufacturing defect that may adversely affec t their utility. They shall beflat, square, true to shape and sound.

Finish shall be matt finish.

Compressive strength shall not be less than 70 N/mm2.

Maximum permissible water absorption shall be 2 percent.

Maximum permissible average wear shall be 2mm. However, for anindividual specimen this value shall be 2.5 mm.


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Tiles meant for dadoing purposes shall not be used for flooring.

17.3.2 Sampling and testing :

Same as that of C eramic tiles.

17.3.3 Acceptance criteria :

Same as that of C eramic tiles.

17.4.0 Acid Resistant tiles :


The tiles shall be of vitreous ware and shall be free form deleterious,substances. The finished tile, when fractured shall appear fine grained intexture, dense and homogeneous. The tiles shall be sound, true to shape,flat free from flaws and other manufacturing defects affecting their utility.

Size of ceramic unglazed vitreous ac id resistant tiles shall be as follows:

i. 100 x 100 (or) 98.5 x 98.5mmii. 150 x 150 (or) 148.5 x 148.5mmiii.200 x 200 (or) 198.5 x 198.5mmHalf tiles for use as full tiles, if manufactured, shall have dimensions thatshall be such as to make the half tiles, when jointed together, match withthe dimension of a full tile.

Thickness shall be 25, 20, 12 & 10mm.

Depth of the grooves on the underside of tiles shall not exceed 3mm.

Tolerance in length, width and thickness of tiles shall be +/-2.5 percent.

Half tiles for use as full tiles, if manufactured, shall have dimensions thatshall be such as to make the half tiles, when jointed together match withthe dimension of a full tile.


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Tolerances in length width and thickness of the tiles shall be +/- 2.5percent. Other requirements shall be in accordance with Table-1 of

IS:4457.

17.5 MARBLE MOSAIC TILE FLOORING:

17.5.1 SCOPE:

This covers the laying and finishing of cement concrete flooring tiles in

floors, wall, staircases, etc.

17.5.2 MATERIALS:

Cement, sand, terrazzo tiles shall conform to the specifications detailed in

the Materials Section.Mixing of mortar shall be done in accordance with the specification laid

down under Cement Mortars.

17.5.3 LAYING:

Subgrade concrete or the RCC slab on which tiles are to be laid shall be

cleaned, wetted and mopped. The bedding of the tiles shall be with

cement mortar 1:5 or as specified. The average thickness of mortar shall

be 30mm and thickness at any place shall not be less than 10mm.

Lime mortar bedding shall be spread, tamped and corrected to proper

levels and allowed to harden for a day before the tiles are laid.

Over this bedding, neat grey cement slurry of honey like consistency shall

be spread at the rate of 4.4 kg/sq.mt over such an area that would

accommodate 20 tiles.

Before laying, the tiles shall be soaked in water for at least 20 minutes and

then allowed to dry for about 10 minutes. It is necessary to have tiles

damp but not wet when they are laid. Tiles shall be fixed by gently

tapping with a wooden mallet till they are properly bedded and in level

with the adjoining tile. The joints shall be kept as thin as possible notexceeding 1.5 mm. Where full-size tiles cannot be fixed, tiles shall be cut to

the required size and their edges rubbed to ensure a straight and true

joint. Tiles which are fixed in the floor adjoining the wall shall enter not less

than 12mm under the plaster, skirting or dado. After the tiles have been


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laid, excess cement coming out through the joints upto the surface shall

be immediately wiped clean.

17.5.4 CURING, POLISHING AND FINISHING:

The day after the tiles are laid all joints shall be cleaned of the grey

cement with a wire brush. The joints shall after 24 hours be filled with

matching cement paste and allowed to set. The same cement slurry shall

be applied to the entire surface of the tiles in a thin coat with a view to

protect the surface from abrasive damage and fill the pin holes that may

exist on the surface.

The floor shall then be kept wet and protected for a minimum period of

seven days before starting the polishing. No one shall be allowed to walk

on the floor during the first 24 hours immediately after the tiles are laid.

The surface shall thereafter be grounded evenly with machine fitted

coarse grade grit block. Water shall be used profusely during grinding. It

shall then be covered with a thin coat of cement mixed with colouring

pigment to match the topping of the wearing surface of the tile sand

second grinding shall then be carried out with machine fitted with fine

grade grit blocks.

The final grinding with machine fitted with the finest grade grit blocks shall

be carried out after 24 hours of completion of second grinding or before

handing over the floor. The entire surface shall be finally washed with

weak solution of soft soap in warm water.

For small areas or where circumstances so require, hand polishing may be

permitted as in the case of skirting, treads and risers of staircase, etc. bythe Engg.-In-Charge / Architects.

MEASUREMENT:

Length and breadth dimensions shall be measured to the correct

centimetre before laying skirting, dado or wall plaster and area


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calculated in square metres correct to two decimal places. No deduction

shall be made nor extra amount paid for any opening in the floor area

upto 0.5 sq.mt. No extra shall be paid for use of cut tiles or for laying the

tiles at different levels in the same room.

17.6 TILES IN SKIRTING

17.6.1 PREPARATION OF SURFACE:

The joints of masonry shall be raked out to a depth of at least 15mm. In

case of concrete and plastered surfaces, the surface shall be roughened

by hacking. All the surfaces receiving tiles shall be c leaned thoroughly,washed with water and kept wet before the tiling is commenced.

17.6.2 LAYING:12mm thick plaster of CM 1:3 or mixed as specified shall be

applied and allowed to harden. The plaster shall be roughened with wire

brushes making grooves of at least 2mm deep before the plaster dries.

The tiles shall be soaked in water. The tiles shall be buttered with a coat of

grey cement slurry and then shall be tamped in position corrected to

proper planes and lines with a wooden mallet. The tiles shall be set in

required pattern and butt jointed with very fine joints. Top of skirting or

dado shall be truly horizontal and joints truly vertical unless specified

otherwise. The skirting or dado shall rest on the top of flooring. The

projec tion of skirting from the finished wall surface shall not be more than

12mm.

17.6.3 POINTING AND FINISHING:

J oints shall be c leaned off grey cement grout with wire brush or trowel to

the depth of 2 to 3mm and all dust and loose mortar removed. J oints shall

then be flush pointed with white cement added with colouring pigment if

required to match the colour of the tiles. The wall shall be kept wet at

least for seven days. The finished wall shall not sound hollow when tapped

with a wooden mallet.


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18.1.4 Causes for rejection:

Stone slabs not c onforming to the size, colour, texture and other criteriamentioned above shall be rejected by the C lient/Consultant.

19. Water Proofing

All water proofing works to be carried out in this scope of work shall be

through the approved agencies / any other reputed approved local

agency.

Contractor will be required to submit a guarantee in respect of

performance of waterproofing for 10 years on stamp-paper. In addition tothis, an amount equal to 10% of cost of waterproofing items shall beretained as retention money for 2 years from the date of completion,which shall be returned only after successful completion of this period.

20.0.0 Paints

20.1.0 Enamel paint:


Paint and enamel shall be of approved quality. Colour for enamels shallconform to IS:5. These shall always meet the requirements (colour andspace) of the client/consultant/architect.

These shall be purchased from reputed manufacturers only as directed bythe client/consultant.

Under no c ircumstances the paint shall be diluted with linseed oil or anyother material before application. The method of application shall be as

prescribed by the manufactures.

Paint shall not show excessive setting in freshly opened c an and shalleasily be mixed with paddle to a smooth homogeneous state.

While brushing, the paint shall be easily brushable, possess good levelingproperties with no running or sagging tendenc ies.


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The paint shall dry to a smooth uniform finish free from roughness,

unevenness and other imperfections.

20.1.2 Primer:

Primers shall be red oxide.

20.1.3 Packing and Marking:

Packing and marking of packages of paints, enamels & primers shall be inaccordance with IS:5661.

20.1.4 Sampling:

Representative samples of the material shall be drawn as prescribedunder 3 of IS: 101 whenever direc ted by the Client/C onsultant.

20.1.5 Storage:

Paints of all types shall be stored in a cool dry place, preferably in agodown spec ifically made for the purpose. In general, storage of paintsshall be in accordance with IS:4082.

20.2.0 Plastic emulsion paint:

Plastic emulsion paint for interior and exterior use shall conform to IS:5411(Parts-1 &2) respectively.


a. The emulsion paint and primers in general shall be of approved quality,colour, shade and brand as direc ted by the Client/Consultant.

b. The material shall consist of pigments with suitable extenders in suitableproportions, in a medium consisting of any stable synthetic polymeremulsion in water, with suitable other ingredients as may be

Documents

7 Technical Specification Civil