REINFORCED CEMENT CONCRETE WORK.

SPE-CIFICATIONS 91 a> 92

CONTENTSLIST OF MANDA TORY TESTS / LIST OF BIS CODES

68

5.0

Reinforced Cement Concrete Work 71

5.1.0

Materials 71

5.1.1

Water, Cement, fine and Coarse aggregate 71-

Steef for reillforcement5.1.2 71

5.1.3

Stacking & Storage 73

5.2

Form work (Centring & Shuttering) 74

5.2.1

Form work 74

5.2.2

Design & Tolerance in construction ·74

5.2.3

General Requirement 74

5.2.4

Surface Treatment -76

'5.2.5

Inspection of Form work 76

5.2.6

Measurements 77

5.2.7

Rate 78

5.3

Reinforcement 78

5.3.1

General requirement 78

5.3.2

Placing in position 80

5.3.3.

M~asurements 80

5.3.4

Rate 81

-S.4 Concreting /81

5.4.1

Consistency 81

5.4.2

Placing of concrete 82

5.4.3

Compaction 82

5.4.4

Construction joints 83

5A.5

Expansion joints 83

5.4.6

Curing 83

5.4.7

Finishing 83

5.4.8

Strength of concrete 85

5.4.9

Testing of concrete 85

5.4.10 Standard of acceptance

-85

65

5.4.11 Measurements 89

5.4.12 Tolerances

90

5.4.13 Rate

90

5.5

Encasing Rolled Steel Sections 91

5.5.11

Wrapping 91

5.5.2

Form work 91-.....•

.5.5.3Concreting 91

5.5.4

Measurements 91

5.5.5

Rate 92

5.6

Precast Reinforced Concrete 92

5.6.1

General Requirements 92to 5.6.4

5.6.5

Curing 92to 5.6.6

5.6.7

Marking 92to 5.6.8

5.7 -

Precast Cement Concrete Jali 92

5.7.1

Fixing 93..J

5.7.2

Measurements . 93

5.7.3

Rate 93

5.8

Design Mix Concrete 93

5.8.0

Definition 93

5.8.1

Materials 93

5.8.2

Scope 93

5.8.3

Data for Mix design 93

5.8.4

Production of Concrete 97

5.8.5

Batching 98

5.8.6

Mixing 99

5.8.7

Laying 99

5.8.8

Curing 99

66

5.9

5.8.9 Approval of design mix

5.8.10 Work strength Test5.8.11

Standard of Acceptance

5.8.12 Example for mix design5.8.13 Measurements5.8.14 Tolerances5.8.15 Rate

Precast Reinforced ConcreteDoor &. Window frames

5.9.2 Shape & dimensions ­

5.9.3 Materials

5.9.4 Castings

5.9.5 Mould

5.9.6 Protections & Curing

5.9.7 Hinges

.5.9.8 Arrangements for-door & window fixtures

5.9.9 Fastners

5.9.10 Erection

99

99

99

100

103

103

103

103

103

103

103

104

104

104

104

104

104

Fig. ],2 & 3

Fig. 4 & 5

Fig. 6 & 7

Fig. 8

Fig. 9

Fig. 10 to 23

Fig. 24 & 25

Fig. 26

Fig. 27 & 28

Fig. 29 & 30

Appendix A - Work test for concrete_ (Mandatory lab test)

Appendix B - Rebound Hammer test

Appendix C - Additional tests for concrete

Appendix D - Register of work Test of concrete

Typical set up of steel wall form work & ties

Typical standard units & Components of form work.

Typical arrangements of column form work.

Typical details of Beam Head and Stiffener

Typical details of multi-stage shuttering

Details of expansion joints

Seismic separation joints, details at floor and roof level

. Construction joints

Encasing rolling steel sections

R.C.C. door & window frames

67

105

107

108

110

113 to 1I5

116 &117

118 & 119

120

121

122 to 126

127

128

129

130 to 13 1

'.

Chapter - 5LIST OF MANDATORY TESTS:

Meterial Clause Test Field/Laboratorytest

Test Procedure Minimum

quantity ofmaterial/work

for carryingout the test.

Frequency of testing

5.4.1b) Slump testField Appendix'D'

0\-

of chapter

00

04, concrete

Reinforced

5.4.9c) Cube testLab .Appendix t A'Cement

Page 105Concrete

a) 20 cumin slab, beams&..ronnectedColumns

b) 5 cum in .Columns

Note: For all other small items and where RCC done in a day is less than 5 cum;testmay be carried out as required by Engineer-in-Charge. '

"

Water for const

mction purposes5.1.1 a) Chemical & Lab

physicalproperties

IS 8025~1964 water fromeach source

Before comme , .-cement of work

and thereafter every threemonths till .

completion of work

Once in a day

a) Every 20 cumof a day'sCorcreing

b) ~very 5 cum

5.4.10.5. d) Hammer(A) Test

Field Appendix 'B'page ... 107

,

Once in every three months or asdirected by the :i

Engineer- in-charge

R.c.c. Work

List of Bureau oflndian Standard Codes.

I. IS 226-1975 Structural Ste'el

2.

IS 432-1982 (Pt.I) Specification for mild steel and medium tensile steel barsand hard drawn steel wire for concrete reinforcement Part'I mild steel and medium tens~le steel bars.

3.

IS 432-1982 (Pt. II) Specification for mild steel and medium tensile steel barsand hard drawn steel wire for concrete reinforcement - PartII Hard drawn steel wire.

4.

IS 456 - 1978 Code of Practices for Plain and Reinforced concrete

5.

IS 516 -1959 Method of test for strength of concrete.

6.

IS 716-1987 Specification for Pentachlorophenol

7.

IS 1199 -1959 Method of sampling and analysis of Concrete

8.

IS 1200-1974 Method of measurement of building and(part II)

civil engineering work-concrete work

9.

IS 1200-1982 Method of measurement of building and civil(part V)

engineering (part5-Form work)

10.

IS 1566-1985 Specification for hard-drawn steel wire fabric for Concreterequirement.

II.

IS 1599-' 1985 Method for bend test

.12.

IS 1343-1980 Code of Practice for Prestressed Concrete

13.

IS 1608-1972 .Method for tensile testing of steel products

14.

IS 1786-1985 Specification forhigh strength deformed steel and wires forconcrete reinforcement

15.

IS 1791-1985 Specification for batch type concrete mixes

16.

IS 2502 - 1963 Code of practice for bending and fixin[ of bars for concretereinforcement

17.

IS 2751 - 1979 Recommended practice for welding of mild steel plain anddeformed bars for reinforced construction

18.

IS 4925 - 1968 Batching PlantsSpecification for concrete batching and mixing plant

69

19. IS 6523 - 1983

20. IS -10262-1982

21. IS 13311 (Pt. 1)1992

22. IS 13311 (Pt. II) -1992

Specification for precast reinforced concrete door, windowframes

Recommended guidelines for concrete mix Design

Indian Standard for non destructive testing of concrete.Method of test for ultrasonic Pulse velocity

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

70

, c) Concreting: 1) Cast-in-situ 2) Precast

5.1 Materials

5.0 General: Reinforced cement concrete

work may be cast-in-situ or Precast as may bedirected by Engineer-in-charge according tothe nature of work.Reinforced cement con­

crete work shall comprise of the followingwhich may be p~jd separately or collectively asper the description of the item of work.

a) Form work (Centring and shuttering)

b) Remforcement

b)5. REINFORCEDCONCRETE

CEMENTWORK

Hard drawn steel wire conforming to IS432 (Pt, II) 1982

c) High strength deformed steel bars con­forming to IS 1786-1985

d) Hard diawn~teel wire fabric conformingto IS 1566-1982

e) Structural steel section conforming to IS226-1975

5.1.2.2 Types and Grades

_ Reinforcement supplied in accordance withthis standard shall be classified into the follow­

ing types.

a) Mild steel bars: It shall be supplid in thefollowing two grades

5.1.1' Water, cement, fine and coarse aggre­gate shilll be as specified under respectiveclauses of chapter 03-mortars and chapter 04-concrete work as applicable. -

5.1.2 Steel for reinforcement

5.1.2.1 The steel used for reinforcement shall

be any of the following types

. a) Mild steel and medium tensile bars con-.forming to IS 432 (Pt.I) .1982

i) Mild steel bars grade I designated asFe 41O-S

ii) Mild steerbars grade II designatedas Fe 410-0

b) Medium tensile steel bars, grade II desig­nated as Fe 540-W-HT.

5.1.2.3 Mild steel and Medium tensile steel

Physical requirement are given in the follow­ing table I

S.No. Type and nom4tal sizeof bar

TABLE I

Ultimatetensile

stress'

N/mm2minimum

Yieldstress

N/mm2minimum

Elongationpercentminimum

1.

2.

3.

Mild steel grade IFor bars upto andincluding 20mm.

41025023

For bars over 20 mm upto and including 50mm

41024023

Mild steel grade IT

For bars upto and including. 20mm

37022523

For bars over 2Omm, upto and including 50mm370;215'23

Medium tensile steelFor bars upto & including 16mni

54035020

For bars over 16mm, upt~ and including 32mm

54034020

For bars over 32mm, upto and including 50mm

51033020

71

Nomimil mass/weight The tolerance onmass/weight for round and square bars shall be

the percentage given in Table II of the mass/weight calculated on the basis that the massesof the bar/wire of nominal diameter and of

density 0.785 kg/cm3• or .00785 kg/mm3•

Elongation Percent on gauge length 5.6 5 ISOwhere so is the cross sectional area of the test

piece.

Note 1. Grade (II) Mild steel bars are not rec­ommended for the use in structures

located in earthquake zone subjectedto severe damage and for structuressubjected to dynamic loading (otherthan wind loading) such as railway andhighway bridges.

2.

-Welding of reinfocement bars coveredin this specification shall be done inaccordance with the requirements ofIS 2751 - 1979.

Table II(Tolerance on nominal mass)

Nominal size in mmTolerance on the nominal mass Percent

Batch Individual Individual

sample + sample for coil (-x-)

~) upto and including 10 ±7±8 ±8

b)

over 10', upto and including 16 +5-6 +6

c)

over 16 ±3-4 ±4

+

for individual sample plus tolerance is not'specifie~(x)

For coil batch tolerance is not appliable

Tolerance shall be determined in accordance with method given in IS 1786-1985

TESTS - Following type of lab test shall becarried out

1) Tensile Tests

This shall be d~me as per IS 1608 - 1972

2) Bend Test

1)1is shall be done as per IS 1599 - 1974

3) Re-testThis shall be done as per IS 1786 - ·1985

4.) RebendTestThis shall be done as per IS 1786 - 1985

Should anyone of the test pieces' firstselected fail to pass any of the tests speci-

72

fied above, two further samples shall beselected for testing in respect of eachfailure. Should the test pieces from boththese additional samples pass, the materi­als represented by the test samples shallbe deemed to comply with the require­ment of the particular test. Should the testpiece from either of these additionalsamples fail, the material represented bythe test samples shall be considered as nothaving complied with standard.

5.1.2.4 High strength deformed bars & wires'Shall conform to IS 1786 - 1985. The physicalproperties for all sizes of steel bars are men~tioned below in Table III.

TABLE-ill

S.No. Property Grade

Fe 415

Fe 500Fe 550

1.

0.2% proofStress / yieldstress, min.N/mm2

. 415500550

2.

Elongation, .percent min. ongauge length 5.65."jA,Where A is the -X -Sectional Areaof the test piece.

14.5128

3.

Tensile strength 10% more8% more than6% more thanthan actual

actual 0.2% .actual

0.2% proofproof stress0.2% proof

stress butbut not less thanstress but not

not less .545 N/mm2less than

than 465585 N/mm2

N/mm2

a) From cutting of bars

Tests: Selection and preparation of Test sampleAll the tests pieces shall be selected by theEngineer-in-Charge or his authorised repre­sentative either-

b)

or

Ifhe so desires, from any bar after it hasbeen cut to the required or specified sizeand the test piece taken from any part ofit.

In neither case, the test pieces shall be

detached from the bar or coil except in tljepresence of the Engineer~in-Charge orhis authorised representative.

The test pieces obtained in accordancewith as above shall be full sections of tl)e

bars as rolled arid su~sequently coldworked and shall be subjected to physical­tests without any further modifications.

N?deductions in size by machining orotherwise shall be permissible. No test

_piece shall be enacted or otherwise sub­ject to heat treatment. Any straightening

which a test piece may require shall bedone cold.

Tensile test: This shall 'be done as per IS1599:..1966

RE - test : This shall be done as per IS1786-1985,

Rebend test:' This shall be done as perlS 1786-1985. -

5.1.3 Stacking arid storage : Steel for rein­forcement shall be stored'in such a way as to

6-4/CPWD/ND/92 73

prevent distorting and corrosion. Bars of dif­ferent classifications, sizes and lengths shall bestored separately to facilitate issue in such sizesand lengths to cause minimum wastage incutting from standard length.

Forms shall be so constructed as to be remov­

able in sections in the desired sequence, with­out damaging the surface of concrete ordistrubing other sections. Care shall be taken tosee that no piece is keyed into the concrete.

5.2 Form wor\ (centring & shuttering) 5.2.3.1 Material for form work

If

(Note- Tolerance appl y to concrete dimensconsonly, and not to positioning of vertical steel ordowels.)

5.2.1 Forrn work: Form work shall include

all temporary or permanent forms or mouldsrequired for forming the concrete which is cast­in-situ, together with all temporary construc­tion required for their support.

5.2.2 Design & Tolerance in Construction

Form work shall be designed and constructedto the shapes, lines and diamensions shown onthe df.awings with the tolerances given below.

a) Deviation from specifieddimensions of cross sectionof columns and beams +12 mm

b) Deviation from dimensions

of footings +12mm

i) Dimension in Plan +50 mm

ii) Eccentricity in plan0.02 times the width of the foot­

ings in the direction of deviationbut not more than 50 mm.

iii) 'Thickness+ 0.05 times the specified thick­ness.

5.2.3 General Requirement : It shall bestrong enough to withstand the dead and liveloads and forces caused by ramming and vibra­tions of concrete and other incidental loads,

imposed upon it during and after casting ofconcrete. ltshall be made sufficiently rigid byusing adequate number of ties and braces,Screw jacks or hard board wedges where re- '

_ quired shall be provided to make up any settle­ment in the form work either before or duringthe placing of concrete.

74

a) Propping and centring

All propping and centring should beeither of steel tubes with extension

p~eces or built up sections of rolledsteel.'

5.2.3.2 a) Centring/staging

Staging should be as designed withrequired extension pieces as ap­proved by Engineer-in-Charge toensure proper slopes, as per designfor slabs/beams etc. and as per lev­els as shown in drawings. All thestaging to be either of Tubular steel

structure with adequate bracings asapproved or made of built up struc­tural sections made from rolledstructural steel sections.

b) In case of structures with two ormore floors, the weight of concrete,centring and shuttering of any up­per floor being cast shall be 'suitablysupported on one floor below thetop most floor already cast.

c) Form work arilt'concreting of upperfloor shall not be done until con­crete of lower floor has set atleast

for 14 days.

5.2.3.3 Shuttering: Shuttering used shall beof sufficient stiffness to avoid excessive de­

flection and joints shall be tightly butted toavoid leakage of slurry. If required, rubberisedlining of material as approved by the Engineer­in-Charge~shall be provided in the joints.

Steel shuttering used for concreting should besufficiently stiffened; The steel shutteringshould also be properly repaired before use and

properly cleaned to avoid stains, honey comb­ing, seepage of slurry through joints etc.

5.2.3.7 Removal of Form work (Strippingtime)

(a) Runner Joists

RSJ, MS Channel or any other suitablesection of the required size shall be usedas runners.

In normal circumstances and' where ordinaryportland cement is used, forms may generallybe removed after the expiry of the followingperiods:

(b) A ssembly of beam head over props.Beam head is an adopter that fits snuglyon the head plates of props to providewider support under beam bottoms.

a) Walls, columns andvertical faces ofall structuralmembers

24 to 48 hours

. as may be decidedby the Engineer-in­charge

Note-2

Note-3

For rapid hardening cement, 3/7 of above peri-,~,ods will be sufficient in all cases except forvertical side of slabs, beams and columns whichshould be retained for atleast24 hours.

The number of props left under, their sizes anddisposition shall be such as to be able to s~felycarry the full dead load of the slabs, beam orarch as the case may be together with any liveload likely to occur during curing or furtherconstruction.

14 days

28 days

21 days

7 days

14 days

b) Slabi) Spanning upto

4.50 M

ii) Spanning over4.50M

c) Beams and archesi) Spanning upto

6M

ii) Spanning over6 M & Upto 9 m

iii) Spanning over9M

Note-1

For othertypes of cement, the stripping timerecommended for ordinary portland cementmay be suitably modified. If portland pozzo­lana or low heat cement has been used for,

concrete, the stripping time will be 10/7 of theperiod stated above.

5.2.3.6. WALLS

5.2.3.4 From work shall be properly designedfor self weight, weight of reinforcement, weightof fresh concrete, and in addition, the various

live loads likely to be imposed during theconstruction process (such as workmen, mate­rials and equipment). In case the height ofcentring exceeds 3.50 metres, the prop may beprovided in multi-stages. A typical detail ofmultistage shuttering is given in Fig.9.

5.2:3.5 Camber : Suitable camber shall be

provided in horizontal members of structure,especially in cantilever spans to counteract theeffect of deflection. The form work shall be so

assembled as to provide for camber. The cam­ber for beams and slabs shall be 4 mm per metre

(1 in 250) or as directed by the Engineer-in­charge, so as to offset the subsequent deflec­tion. For cantilevers the camber at free end

shall be 1/50 th of the projected length or asdirected by the Engineer-in-charge.

5.2.3.5.1 Typical arrangement of fonn workfor 'Beams, columns and walls 'are shown in

Figure 1 to 8 a.nd form secured by wall ties isshown in Figure 3.

The form faces have to be kept at fixed distanceapart and an arrangement of wall ties withspacer tubes or bolts is considered best. Atypical wall form with the componcnts identi­

fied is given in Fig. 1,2&3, The two shutters ofthe wall are to be kept in place by appropriateties, braces and studs. Some of the accessories

used for wall forms are shown in Fig3.

75

In case of cantiliver slabs and beams, the

centring shall remain till structures for counteracting or bearing down have been erected andhave attained sufficient strength.

Proper precautions should be taken to allow forthe decrease in the rate of hardening that occurswith all types of cement in cold weather andaccordingly stripping time shall be increased.

Work damaged through premature or carelessremoval of fonns shall be reconstructed.

5.2.4 Surface Treatment

5.2.4.1 Oiling the surface

Shuttering gives much Jonger service life if thesurfaces are coated with suitable mould oil

which acts both as a parting agent and also_gives surface protections

A typical mould oil is heavy mineral oil orpurified cylinder oil containing not less than ­5% pentachlorophenol confonning to IS 716­1987 well mixed to a viscosity of 70-80centipoise.

After 3-4 uses and also in cases when shutter­

ing has been stored for a long time; it should bereooated with mould oil before the next use.

5.2.4.2. The design of fonn work shall con­

form to sound Engineering practices and rel­evant IS codes

5.2.5 Inspection of Form work

The completed fonn work shall be inspectedand approved by the Engineer -in-charge beforethe reinforcement bars are placed in position.

Proper fonn work should be adopted for con­

creting so as to avpid honey combing, blowholes, grout loss, s'tains or discolouration of

76

concrete etc. Proper and accurate -alignmentand profile of finished corecrete surface will beensured by proper designing and erection offonn work which will be approved by Engi­neer-in-Charge.

Shuttering surface before concreting should befree from any defect/deposits and fully cleanedso as to give perfectly straight smooth concretesurface. Shuttering surface should be thereforechecked for any damage to its surface andexcessive roughness before use.

5~2.5.1 Erection ofFonn Work (centring andshuttering). Following points shall be borne inmind while checking during erection.

a) Any member which is to remain in posi­tion after the general dismantling is done,should be clearly marked.

/b) Material used should be checked to en­

sure that, wrong items / rejects are notused.

c) If there are any excavations nearby whichmay influence the safety offonn works,corrective and strengthening action mustbe taken.

d) i) The bearing soil must be sound andwell prepared and the sole platesshall bear well on the ground.

ii) Sole plates shall be properly seatedon their bearing pads or sleepers.

iii) The bearing plates of steel propsshall not be distorted.

iv) The steel parts on the bearingmem­bers shall have adequate b~aringareas.

-e) Safety measures to prevent impact oftraffic, scour due to water etc, should be

taken. Adequate -precautionary measuresshall be taken toprevem accidental im­pacts ~tc.

f) Bracing, struts and ties shall be installedalong with the progress of fonn work toensure strength and stabili ty of fonn work

at intennediate stage. Steel sections (es- p)Guy ropes or stays shall be tensionedpecially deep sections) shall be adequately

properly.restrained against tilting, over turning and fonnwork should be restrained against

q)There shall be adequate provision for nle;

horizontal loads. All the securing devices

movement and operation of vibrators and

and bracing shall be tightened.

other construction plant and equipment.

g)

The stacked materials shall be placed as r)Required camber shaH be provided over

catered for, in the design.

long spans.

h)

When adjustable steel props are used, s)Supports shall be adequate, and in plumb

they should:-.

within the specified to~erances.

l.

be undamaged and not visibly bent.

2.

have the steel pins provided by the 5.2.6MEASUREMENTS

manufacturers for use.5.2.6.1 General

3.

be restrained laterall ynear each end,The fonn work shall include the following

4.

have means for centralising beamsplaced in the forkheads.

a)Splayed edges, notchings, allowance for

overlaps and passings at angles, sheath-i)

Screw adjustments of adjustable props ing battens, strutting, bolting, nailing,

shall not be over extended .

wedging, easing, striking and removal..j)

Double wedges shall be provided for b)All supports, struts, braces, wedges as

adjustment of the fOnTIto the required

well as mud sills, piles or other suitable

position wherever any settlement/ela'stic

arrangements to support the fonn work.

shortening of props occurs. Wedgesc)

Bolts, wire ties, clamps, spreaders, nailsshould be used only at the bottom end of

single prop. Wedges should not be too

or any other items to hold the sheathing

steep and one of the pair' should be tight - .

together.

ened/clamped down after adjustment to

d)Working scaffolds, . ladders, gangways,prevent their shifting.

and similar items.

k)

No member shall be eccentric upon verti- e)Filleting to fonn stop chamfered edges ofcal member. ..splayed external angles not exceeding 20

i)

The number of nuts and bolts shall be mm wide to beams, columns and the ~e.

adequate.

±)Where required, the temporary openings

m)

All provisions of the design and/ordraw~provided in the fonns for pouring con-

ings shall be complied with. 1 •

crete, inserting vibrators, and cleaning

holes fot removing rubbish from the inte-n)

Cantilever supports shall be adequate. rior of the sheathing before pouring con-crete.0)

Props shall be directly under one another- .

in multistage constructions as far as pos-

g)Dressing with oil to prevcnt adhesion and

sible.h)

Raklng or circular cutting

77

5.2.6.2. CLASSIFICA TION OF MEA­SUREMENTS

Where it is stipulated that the fonn work shallbe paid for separately, measurements shall betaken of the area of shuttering in contact withthe concrete surface. Dimensions of the fonnwork shall be ,measured correct to a cm. The

measurements shall be taken separately for thefollowing

a) Foundations, footings, bases of columnsetc~ and for mass concrete and precastshelves. '

b)· Walls (any thickness) including attachedpilasters, butteresses, plinth and stringcourses etc.

c) Suspended floors, roofs, landings, shelvesand their supports and balconies.

d)

Lintels beams, girders, bressummers andcantilevers

e)

Columns, pillars, posts and struts.

f)

Stairs (excluding landigs) except Spiral .Staircase

g)

Spiral staircases (including landings)

h)

Arches

i)

Domes, vaults, shells roofs, archribs andfolded plates

j)

Chimneys and shafts

k)

Well steining

1)

Vertical and horizontal fins individmlllyor fonning box, louvers and bands

m)

Waffle or ribbed slabs

n)

Edges of slabs and breaks in floors andwalls (to be measured in running metreswherebelow 200 mm in width or thick-ness)

0)

Cornices and mouldings

78

p) Small surfaces, such as cantilevers ends,brackets and ends of steps, caps and boxesto pilasterS and columns and the like.

q) Chullah hoods, weather shades, chajjas,corbels etc. induding edges and

r) Elevated water reservoirs.

5.2.6.3 Centring, and shuttering where ex-lceeding 3.5 metre height in one floor shall be •.measured and paid for separately. ~

5.2.6.4 Where it is not specifically stated in

the description of the item that fonn work shallbe paid for separately, the rate oftthe RCC itemshall be deemed to include the cost of fonnwork.

5.2.6.5 No deductions from the shuttering dueto the openings/obstructions shall be made ifthe area of such openings/obstructions does notexceed 0.1 square metre. Nothing extra shall bepaid for fonning such openings.

5.2.7 Rate-The rate of the fonn work in­

cludes the cost oflabour and materials requiredfor all the operations described above

I

5.3. -/ Reinforcement:

5.3.1 General requirements: Steel Con­forming to para 5.1.2 for reinforcment.shall be

, clear and free from loose milscales, dust, loose

rust, coats of paints, oil or other coatings whichmay destroy or reduce bond. It shall be storedin such a way as to avoid distortion and toprevent deterioration and corrosion. Prior to

assembly of reinforcement on no account anyoily substance shall be used for removing therust.

5.3.1.1 Assembly of reinforcement

Bars shall be bent correctly and accurately tothe size and shape as shown in the detaileddrawing or as directed by Engineer-in-Charge.

Preferably bars of fullle!1gth shall be used.Necessary cutting and straightening is alsoincluded. Over lapping of bars, where neces­sary shall be done as directed by the Engineer-

in-Charge. The overlapping bars shall not toucheach other and these shall be kept apart with

concrete between them by 25 mm or 11/4 timesthe maximum size of the coarse aggregatewhichever is greater. But where this is notpossible, the overlapping bars shall be boundtogether at intervals not exceeding twice thedia. of such bars with two strands annealed

steel wire of 0.90 mm to 1.6 mm twisted tight.The overlaps/splices shall be staggered as perdirections of the Engineer-in-Charge. Butinnocase the over lapping shall be provided in morethan 50% of cross sectional area at one section.

5.3.1.2 Bonds and Hooks Forming End An­chorages

Reinforcement shall be bent and 1hed in accor­

dance with procedure specified in IS 2502­-1963, code of practice for bending and fixing ofbars for concrete reinforcement. The details of

bends and hooks are shown below for guid­ance.

a) U type Hook

In case of mild steel plain bars standard Utype hook shall be provided by bendingends of rod into semicircular hooks hav­

ing clear diameter equal to four times thediameter of the bar.

U- TYPE HOOK"..

Note:- In case of work in seismic zone, the

79

size of hooks at the end ofthe rod shall be eighttimes the diameter of bar or 'as given in thestructural drawing.

b) Bends

Bend forming anchorage to a M.S. plainbar shall be bent with an internal radius

-equal to two times the diameter of the barwith a minimum length beyond the bendequal to four times the diameter of thebar.

f4cl ~I\.J,

~2-d.

zJ

BENDS

5.3.1.3 Anchoring bars in tension

Deformed bars may be used without end an­chorages provided, development length require­ment is satisfied. Hooks should normally beprovided for plain bars in tension. Develop­ment length of bars will be determined as perclause 25.2.1 ofIS 456-1978.

5.3.1.4 Anchoring bars in compression

The anchorage length of straight bar in com­pression shall be equal to the 'Developmentlength' of bars in compression as specified inclause 25.2.1 of IS 456-1978. The projectedlength of hooks, bends and straight length~beyond bend, if provided for a bar in compres­

sion, shall be considered for developmentlength.

5.3.1.5 Binders, stirrups, links and the like:In case of binders, stirrups, links etc. the straightportion beyond the curve at the end shall be notless than eight times the nominal size of bar.

5.3.1.6 Welding of bars

5.3.2 Placing in position/'

Wherever facility' for electric arc welding isavailable, welding of bars shall be d9ne in lieuof overlap. The loc~t;ion and type of 'weldingshall be' got appr~ved by the Engineer-in­Charge. Welding sliallbe as per IS '2751- 1979for mild steel bars and for cold worked bars.

5.3.2.1 Fabricated reinforcement bars shall be

placed in ~siti6n as shown in the drawiiigs or,as directed by the Engineer-ill-Charge. Thebars crossing one another shall be tied together<u every intersection with two strands of an­nealed steel wire 0.9 to 1.6 mm thickness

twisted tight to make the skeleton of the steelwon: ri'gid so that the reinforcement does notget displaced du'ring deposition of concrete.

Tack welding in crossing' bars shall also bepermitted in lieu of binding with steel wire-ifapproved by Engineer-in-Charge.

5.3.2.2 The bars shall be kept in correct posi­tion by the folloWing,'methods :

±15mm

±lOmm

Tolerancein spacing

a) Foreffectivedepili,200mm or less •

b) For effective depili, moreilian 200 mm

Wherever tack weldiiig isu~ in lieu of bind­ing, suchW~lds shall not be measured. Chairsseparators etc. shall be provided as directed bythe Engineer-in-Charge & measured separatelyand paid for.

d)" In case of other R.C.C'- structure such asarches, domes, shells, storage tanks etc. acombination of cover blocks, spacers and

'templates shall be used ,as directed byEngineer-in-Charge.

5.3.2.3' Tolerance' on placing of reinforce-merit '

Unless otherwise specifi~9 by the Engineer-in­Charge, reinforcement shall be placed within

, the following tolerances :

The cover shall in no case be reduced b~}norethan one third of specified cover or 5 mm whichever is less. '

5.3.2.4 Bending at construction joints ,

Where reinforcement bars are bent aside at

construction joints and afterwards bent backinto their original position care should be take.nto ensure that at no time the radius of the bend

is Jess than 4 bar diameters for plain mild streelor6 bar diameters for deformed bars. Care shall

also be taken when bending back bars to ensure, ff

that the concrete around the baris not damaged.

5.3:3 Measurement

'Reinforcement including aHthorisedspacer barsand lappages shalL be measured in, length ofdifferent diameters, as actually (not more thanas specified in the drgs.) used in the worlt:'nearest to a centimetre and their weight calcu­lated on the basis of standard weight given intable - IV 1?elow.,Wastage and unauthorised

;';-::"

overlapsShall not be p~d for. Annealed steel,-,~,wirKrequired for binding or tack welding shall,

not be measured, its cost being included in therate of reinforcement.-

In case of beam and slab construction

precast cover blocks in cement mortar 1:2(1 cement: 2 coarse sand) about 4 x 4 cmsection and of thickness equal to, the

,.. d·:

specified cover shall be placed'betweenthe bars and shutterings, so, as to secureand maintain the requisite cover of con­crete over reinforcement.

In case of cantilevered and dou~ly rein­forced beams or slabs, the"veryical dis­tance between the horizontal bars'shall be

, maintained by introducing chairs, spac­ers or support bars of steel at 1.0 metre orat shorter spacing to avoid sagging.

¥ <

In case of columns and walls, the verticalbars shall be kept in position by means oftimber templates with slots accurately cutin them; or with block of cement mortar1:2 (1 cement: 2 coarse sand) of required

siz~ ,s~tably tied to the reinforcement toensure that they are in correct positionduring concreting.

b)

c)

a)

80

Table IV

Cross Sectional Area and Mass of Steel Bar

Nominal Sizemm

6

7

8

10

12

16

18

20

22

25

28

32

36

40

45

50

Cross Sectional Area

Sq.mm

28.3

38.5

50.3

78.6

113.1

201.2

254.6

314.3

380.3

491. 1

616.0

.804.6

1018.3

1257.2

1591.1

1964.3

Mass per metre RunKg

0.222

0.302

0.395

0.617

0.888

1.58

2.00

2.47'

2.98

3.85

4.83

6.31

7.99

9.85

12.50'

15.42

Note: These are as per clause 5.2 ofIS 1786-1985

5.3.4 Rate: The rate for reinforcement shall

. include the cost. of labour and materials re­quired for all operations described above such

as cleaning of reinforcement bars, straighten­ing, cutting, hooking, bending, binding, plac­ing in position etc. as required or directedincluding tack welding on crossing of bal'S inlieu of binding with wires.

5.4 CONCRETING

. 5AO The concl'ete shall be as specified un­der chapter 04 concrete work: The proportionby volume of !ngredients shall be as specified.

5.4.1 . Consistency: The concrete which willflow slugishly into the forms and 'around the

81

reinforcement without any segregation of coarseaggregate from the mortar, shall be used. Theconsistency shall depend on whether the con­crete is vibrated on or hand tamped. It shall bedetermined by slump test as prescribed in chap­ter"concrete under para 4.2.3 workability.

5.4.1.1 Where considered necessary, the work­ability of the concrete may also be ascertained

by compacting factor test and VEE BEEconsistometer method specified in I.S. 1199­1959 ..For suggested ranges of values of work­

ability of c~ncrete by the above two methods,reference may be made to I.S. 456 - 1978.

5.4.2 Placing of Concrete

5.4.2.1 Concreting shall be commenced onlyafter Engineer- in-charge has inspected the cen­

tering, shuttering and reinforcement as placedand passed the same. Shuttering shall be cleanand free from all shavings, saw dust, pieces ofwood, or other foreign material and surfacesshall be treated as prescribed in 5.2.4.

5.4.2.2. In case of concreting of slabs andbeams, wooden plank or cat walks of chequerredMS plates or bamboo chalies or any othersuitable material supported directly on thecentring by means of wooden blocks or lugsshall be provided to convey the concrete to theplace of deposition without disturbing the rein­forcement in any way. Labour shall not beallowed to walk over the reinforcement.

5.4.2.3 In case of columns and walls, it isdesirable to place concrete without construc­tion joints. The progress of concreting in thevertical direction, shall be restricted to one

metre per hour.

5.4.2.4 The concrete shall be depositep. in itsfinal position in a manner to preclude segrega­tion of ingredients. In deep trenches and foot­ings concerte shall be placed through chutes oras directed by the Engineer-in-Charge. In caseof columns and walls, the shuttering shall be soadjusted that the vertical drop of concrete is notmore than 1.5 metres at a time.

5.4.2.5. During cold weather, concreting shallnot be done when the temperature falls below4.5° C. The concrete placed shall be protectedagainst frost by suitable convering. Concretedamaged by frost shall be removed and workredone.

5.4.2.6 During hot weather precaution shall betaken to see that the temperature of wet con­crete does not exceed 38° C. No concrete shall

be laid within half an hour of the closing timeof the day, unless permited by the Engineer-in­Charge.

5.4.2.7. It is necesary that the time betweenmixing and placing of concrete shall not ex-

82

ceed 30 minutes so that the initial setting. process is not interferred with.

5.4.3. Compaction

5.4.3.1 Concrete shall be com pacted into densemass immediately after placing by means ofmechanical vibrators designed for continuousoperations. The Engineer-in Charge may how­ever relax this conditions at his discretion for

certain items, depending on the thickness of themembers and feasibility of vibrating the sameand permit hand compaction instead. Handcompaction shall be done with the help oftamping rods so that concrete is throughly.compacted and completely worked around thereinforcement, embeded fixtures, and into cor­

ners of the form. The layers of concrete shall beso placed that the bottom layer does not finallyset before the top layeris placed. The vibratorsshall maintain the whole of concrete under

tre;:tment in an adequate state of agitation, suchthat deaeration and effective compaction isattained at a rate commensurate with the supplyof concrete from the mixers. The vibration

shall continue during the whole period occu­pied by placing of concrete, the vibrators beingadjusted so that the centre of vibrations ap­proximates to the centre of the mass beingcompacted at the time oCplacing.

5.4.3.2. Concrete shall be judged to be prop­erl y compacted, when the mortar fills the spacesbetween the coarse aggregate and begins tocream up to form an even surface. When thiscondition has been attained, the vibrator shall

be stopped in case of vibrating tables andexternal vibrators. Needle vibrators shall be

withdrawn slowly so as to prevent formation ofloose pockets in case of internal vibrators. Incase both internal and external vibrators are

being used, the internal vibrator shall be firstwithdrawn slowly after which the external vi­brators shall be stopped so that no loose pocketis left in the body of the concrete. The specificinstructions of the makers of the particular typeof vibrator used shall be strictly complied with.Shaking of reinforcement for the purpose ofcompaction should be avoided. Compactionshall be completed before the initial setting

starts, i.e. within 30 minutes of addition ofwater to the dry mixture.

5.4.4. Construction Joints

5.4.4.1. Concreting shall be carried out con­tinuously upto the construction joints, the po­sition and details of which shall be as shown in

structural drawing or as indicated in fig 26 or asdirected by Engineer-in-charge. Number ofsuch joints shall be kept to minimum. Thejoints shall be kypt at places where the shearforce is the minimum. These shall be straightand shall be at right angles to the direction ofmain reinforcement.

5.4.4.2. In case of columns the joints shall behorizontal and 10 to 15 cm below the bottom of

the beam running int~ the column head. Theportion of the column between the stepping offlevel and the top of the slab shall be concretedwith the beam.

5.4.4.3. When stopping the concrete on a ver­tical plane in slabs and beams, an approvedstop-board (see fig 26 c) shall be placed withnecessary slots for reinforcement bars or anyother obstruction to pass the bars freely without.bending. The construction joints shall be keyedby providing a triangular or trapezoidal filletnailed on the. stop-board. Inclined or featherjoints shall not be permitted. Any concreteflowing through the joints of stop-board shallbe removed soon after the initial set. When

~oncrete is stopped on a horizontal prane, thesurface shaH be roughened and cleaned afterthe initial set.

5.4.4.4: When the work has to be resumed, the

joint shall be throughly clealled with· wirebrush and loose particles removed. A coat ofneat cement slurry at the rate of 2.75 kg ofcement per square metre shaH then be applied

, on the roughened surface before fresh concreteis laid.

5.4.5 Expansion joints

Expansion joints shall be provided as shown inthe structural drawings or as indicated in Fig 10to 25 or as directed by Engineer-in-charge, for

'83

the purpose of general guidance. However it isrecommended that structures exceeding 45 min length shall be divided by one or moreexpansion joints. The filling ofthse joints withbitumen filler, bitumen felt or any such mate:'rial and provision of copper plate, etc. shaH be

paid for separately in running metre. The mea­surement shall be taken upto two places ofdecimal stating the depth and witdth of joint.

'5.4.6. Curing

After the concrete has begun to harden Le.about 1 to 2 hours after its laying, it shaH beprotected from quick drying by covering with

moist gunny bags, sand, canvass hessian or a~yother material approved by the Engineer-in­charge. After 24 hours of laying of concrete,the surface shaH be cured by ponding withwater for a minimum period of7 days from thedate of placing of concrete.

5.4.7. Finishing

5.4.7.1. In case of roof slabs the top suffaceshall be finished even and smooth with wooden

trowel, before the concrete begins to set.

5.4.7.2. Immediately on removal of forms, theR.C.c. ,work shall be examined by the Engi­neer-in~Charge, before any defects are madegood. '

a) The work that has sagged or containshoney combing to an extent deterimental,to structural safety or architectural con­

. cept shaH be rejected as given in para5.4.9.4.for visual inspection test.

b) Surface defects of a minor nature may beaccepted. On acceptance of such a work

,by the Engineer-in-Charge, the same shaHbe rectified as follows :-

1. Surface defects which require re­pair when forms are removed, usu-~ '

allycOrfsist of bulges due to move-mentofforms, ridges at form joints,honey-combed areas, damage re­sulting from the stripping of formsand bolt holes, bulges and ridges are

removed by careful chipping or tool- Where uniform surface colour is

ing and the surface is then rubbedimportant, t!ris defect shall be .rem-

with a grinding stone. Honey-edied by adding 10 to 20 percent of

combed and other defective areaswhite portland cement to the patch-

must be chipped out, the edges be-ing mortar, the exact quantity being

. ing cut as straight as possible apddetermined by trial .

prependicularly to the surface, orThe same amount of care to cure thepreferably slightly undercut to pro-

7.

vide a key at the edge of the patch.

material in the patches ~hould betaken as with the whole structure.2.

Shallow patches are first treated with 'Curing must be started as soon asa coat of thin grout composed of one '.

possible, after the patch is finishedpart of cement and one part of fine

to prevent early drying. Dampsand and then filled with mortar

hessian may be used but in somesimilar to that used in the concrete.

locations it may be difficult to holdThe mortar is placed in layers not

it in place. A membrane curing com-more than. 10 mm thick and each

pOund in these cases will be most

layer is given a scratch fir,llsh to

convenient.

secure bond withthesuccedinglayer. c)The exposed surface ofR. C. C. work shall ..The last layer is finished to match

the surrounding concrete by float-

be plastered with cement mortarJ:3 (1

ing, rubbing or tooling on formed

cement :3 fine sand) of thickness not

surfaces by pressing the form mate-

exceeding' 6 mm to give smooth and

rial against the p~tch while the mor-

evensurface true to line and form. Any

tar is still plastic.

RCC surface which remains permanently

'exposed to view in the completed struc-3.Large and deep patches require fill- ture, shall be con~idered exposed surface

ing up with concrete hel<;lin place -

for the purpose of this specification.by forms. Such patches are rein- Where such exposed surface exceedingforced and carefully dowelled to the

hardened concrete.0.5sqm in each location is not plastered,j

with cement mortar 1:3 (1 cement: 3 fine4.

Holes left by bolts are filled with ~ ~and) 6 mm thick, necessary deductionmortar carefully packed into places

''C shall be made for plastering not done.in small amounts.' The mortar· is mixed as dry as possible, wit:}:ljust

d)The surface which is to receive plaster or

enough water so that it wi!! be tightly

where it is to be joined with brick ma-

compacted when forced'into {>.lace.

'sonry wall, shall be properly roughend

immediately after the shuttering is re-5.Tiered holes extending right through ~oved, taking care tortmove the laitance _

the concrete may be filled with

completely, without distrurbing the con-mortar with a pressure gun similar

crete. The roughening shall be done byto the gun used for greasing motor

hacking. Before the surface is plastered,carS.'

it shaIl be cleaned and yVettedso as to give

6.

Normally, patches appear darkerbond between concrete and plaster.

.•.than the surrounding concrete, pos- RCC work shall be done carefully so that

sibly owing to the presence on theirthe thickness of plaster required for fin-

surface of less cement laitance.ishing the surface is not more than 6 mm.

84

e) The surface of RCC 'slab on which thecement concrete or mosaic floor is 'to belaid shallbe roughenedwithbrushes~hilethe concrete is green. This shall be donewithout disturbing the concrete.

5.4.8: I Strength of Concrete

The compressive strength on work tests fordifferentmixes shallbe as given in table below.

Table

5.4.9. Testing of Concrete

5.4.9.0. Regular mandatory tests on the consis­tency and workability of the fresh concreteshall be done to achieve the specified compres- ,sive strength of concrete. These will be of twotypes

(a) Mandatory Lab. Test

(b) Mandatory Field Te~t

Results of Mandatory Field Test will prevailover mandatory Lab. Test.

5.4.9.1.

(a) Work Test-Mandatory Lab. Test shall becarried out as prescribed in Appendix A,page 105

(bY Mandatory Field Test (Hammer Test).sp.allbe camed out as prescribed in Ap­pendix B, page 107

, -

5.4.9.2. Additional Test - Additional test, if

required; shall be carried out as prescribed inAppendix C, page 108

85

5.4.9.3. Slump Test: This test shall be carriedout as prescribed in Appendix D of Chapfer 04concrete

5A.9.4. Visual Inspection Test: The concretewill be inspected after removal of the formwork as desribedin para 5.4.7.2. The q\festionof carryillg out mandatory test or other testsdescribed in Appendix C (para 5A9.2.) willarise only after satisfactory'report of visualinspection.

The concrete is liable to be rejected if

(i) it is pOrous or honeyco]I1bed'asper para'5.4.7.2.(a)

(ii) its placing has been interrupted withoutproviding a proper construction joint'

(iii) the reinforcement has been displaced be­

yond t~ler~mcespecified; or constructiontolerances have not been met.

However, the hardened concrete may be ac­cepted after carrying out suitable remedial mea­sures to the satisfaction of the Engineer-in­charge at the risk and cost of the contractor.

5.4.10 Standard of Acceptance

5~4.10.1Mandatory Lab. Test.

For concrete sampled ~nd tested as prescribedin Appendix A, page 105 the following re­quirement shall apply.

5.4.10.2. Out of six sample cubes, three cubesshall be tested at 7 days and remaining threecubes at 28 days, if found necessary.

5.4.10.3 7 days' tests

Sampling: The average of the strength of threespecimen shall be accepted as the compressivestrength ofthec0!1crete provided the variationin strength of individual specimen is not morethan ± 15% of the average. Difference betweenthe maXimum and minimum strength shouldnot exceed 30% of average strength of threespeCimen.If the difference between maximumand minimum strength exceeds 30% of theaverage strength, then 28 days' test shan haveto be carried out.

Strength : If the actual average strength ofsample accepted in para 'sampling' above isequal to or higher than specified strength upto15%, then strength of the concrete shall beconsidered in order.

In case the actual average strength of sampleaccepted in the above para is lower than thespecified or higher by more than 15% then 28

days' test shall have to be caf!ied out to deter­mine the compressive strength of concretecubes.

5.4.10.4. 28 days' test

(a) The average of the strength of three speci­men be accepted as the cQmpressivestrength of the concrete provided the,strength of any individual cube shall nei­ther be less then 70% nor higher than130% of the specified strength.

(b) If the actual average strength of acceptedsample exceeds specified strength by more

than 30%, the EI"!-gineer-in-charge, if heso desires, may further investigate thematter. However, if the strength of anyindividaul cube exceeds more than 30%

of specified strength, it will be restrictedto 130% only for computation of strength.

(c) If the actual average strength of acceptedsample is equal to or higher than specifiedstrength upto 30% then strength of theconcrete shall be considered in order and

the concrete shall be accepted at full rates.

(b) If the actual average strength of acceptedsample is less than specified strength butnot less than 70% of the specified strength,the concrete may be accepted at reducedrate at the discretion of Engineer-in­charge (See para 5.4.13.2).

(e) If the actual average strength of acceptedsample is less than 70% of specifiedstrength, the Engineer~in-charge shallreject the defective portion of work repre­sented by sample and nothing shall bepaid for the rejected work. Remedial

86

measures necesary to retain the structureshall be taken at the risk and cost of

contractor. If, however, the Engineer-in­Charge so desires, he may order addi­tional tests (See appendix C page 108) tobe carried out to ascertain if the structure

can be retained.' All the charges in con­nection with these additional tests shall

be borne by the contractor.

5.4.10.5.Acceptance Criteria of MandatoryField Test

(A) Preparation of Standard test cubes forcalibration of rebound hammer at site.

(a) In the beginning the standard testcubes of the specified mix shall beprepared by field units before un­dertaking any concrete work in eachproject.

(b) At least 18 standard cubes necesaryfor formaion of one specimen ofspecified mix. shall be cast by sitestaff well in advance. From these 18

cubes any 3 cubes may be selectedat random to be tested for crushingstrt>'1.gthof 7 days. The crushingstrength obtained should satisfy thespecified strength for the mix as per

specification or agreemen!. If thestrength is satisfactory then the re­maining cubes will form the stan­dard'samples for calibration of re­bound hammer. In case of failure,the site staff should totall y reject thesamples and remove them also andthen make another set of samples byfresh mixing or alternatively, out ofthe remainiung 15 cubes, 3 cubes

will be tested on 28 days. If the 28days' tests are found, satisfactorythen remaining 12 cubes will formthe standard sample for calibrationat 28 days' strength otherwise all

samples shall be rejected and wholeprocedure repeated to form a freshspecimen. All the results shall berecorded in a register.

87

ber'i.e. ±25% or otherwise whole'

procedure shall have to be repeatedand fresh specimen prepared.

These 8 cubes will form one stan­

dard sample in the beginning beforecommencement of work and shall

be ;kept carefully for the visitingofficers who will calibrate their ham­mers on these cubes.

(d) This calibration will be done by t..field staff with their hammer and

then chart of calibration giving thedetails of the average readings, date& month' of casting, mix of the

- concrete etc. shall be prepared andsigned by Engineer-in-Charge andwill be duly preserved for futurereference as and when required

(C) Preserv~tion of cubes at site

Standard sample cubes cast shall be care­fully, preserved at site under the safecustody of AE or his representative formaking them available -together withthecharts, to the officers of QCT NCfE orany other senior departmental- officer,during their inspection of the work. They,will calibrate their hammer on these cubes

if required.

(D) Testing at site

(D-I) Testing equipments

(D-2) Testing will be done generally bynon-destructive methods like re­

bound ,hammers etc. Each fieldDivision/Sub Division/Unit will

purchase rebound hammers andkeep them in working order atwork site. The testing will be doneonly by hammers which are duly,calibrated.

(D- 3) The relative strength of actual fieldwork will be tested with reference

to strength of these standard cubesand calibration charts of a hammer

for determining the rebound num-

88

ber on the field work. The hammer

will be used as per manufacturer'sguidelines at various locations cho­sen at random. The number of

location/reading on each wall;beam or column etc. shall not be

less than 12. All the readingsshould be within the ±25% rangeof values presribed in calibration

chart:r1ormally. However, readingindicating good strength will bewhen it is at par with calibratedvalue or between 100% & 125%

and very g~ if more than 125%.Any value between 100% & 75%of calibrated value shall be consid­

eredsatisfactory. Values from 75%to 50% shall be considered for

payment at rates reduced on proratabasis. The concrete indicating re­bound number less than 50% of

calibrated value shall be rejectedand not paid for.

(E) Acceptance of Field tests and strength

If the relative strength of actual fieldwork is found satisfactory consideringthe calibration charts with reference to '. 'the standard cube test kept at site, therepresentative work will be consideredsatisfactory. If the work is consideredbelow satisfactory, the same will be dealtas stated in para D- 3 above.

(F) 7 days' strength in rare cases only

Normally cube crushing strength on'28days' test shall form the basis of accep­tance. However in rare cases of time

bound projects/urgent repairs 7 days' cubetest strength criteria may 1Jeadopted onsimilar lines using 7 days' standard test

cubes and calibration graphs/curves/chartsfor 7 days' in lieu of 28 days' and testingwork done at 7 days'.

(G) Precautions

(G-1) The testing shall be done gener­ally as per the guidelines of manu-

facturer of the apparatus & strictlyin accordance willi the procedurelaid down in clause 6 of IS 13311

(part 2): 1992 Indian Standard forNon-Destructive Testing of con­crete-Method of Test by ReboundHammer.

(0-2) The rebound ha.."llmers are influ­enced by number of factors liketype of cement aggregate, ,surfaceconditions, moistllre content, ageof concrete & extent of calibrationof concrete etc. Hence care shall

be taken to compare the cement,aggregate etc. and tested under the·similar surface conditions havingmore or less same moisture con­

tent and age. However· effect ofage' can be .ignored for concretebetween 3 days & 3 months old.

5.4.H. Measurement

5.4.11.1 Dimensions shall be measured near·

est to a em except for the thickness of slabwhich shall be measured correct to 0.5 cm. The

areas shall be worked out nearestto 0.01 sq. mt.The cubical contents shall be worked out tonearest 0.01 cubic metre.

S.4.n.2. Reinforced cement concrete whether

cast-in situ or precast 3hall be classified andmeasured separately as follows.

(a) Raft, footing, bases of columns etc. andmass concrete.

(b) Walls (any thickness) including attachedpilasters, buttresses, plinth and stringcourse, fillets etc.

(c) Suspended floors, roofs, landings and'. balconies.

(d) Shelves

(e) Chajjas

(1) Lintel, beams and bressummers.

(i) Columns, pillars, piers, abutments, postsarid struts.-"

7-4/CPWD/ND/92 89

'-

(h) Stair-cases including waist or waistlessslab but excluding landing except in (i)below.

(i) Spiral stair-case (including landing)

(j) AJches, arch ribs, domes and vaults

(k) Olimneys and shafts

(1) Well steining

,,(m) Vertkal and horizontal fins individuallyor fonning box, louvers and facias.

(n) Kerbs, steps and.the like.

(0) String courses, bands, coping, bedplare.s,anchor blocks, plain window sills a.nd thelike.

..(p)" Mouldings as in cornices window sills

etc.

(q) Shell, dome and folded plates.

(I') Extnt for shuttering in circular work inplan ...

5.4.11.3. Work under the following catergoriesshall be measured separately.

(a) Rafts, footings, basis of columns etc. andmass concrete.

(b) All other items upto floor two level,(c) From floor two level to floor threeJevel

and so on.

(d) R.C.C. above roof leve.l shall be mea­sured along with R.C.C. work in floorjust below.

5.4.11.4. No deduction shall be made for the

following:" ....

(a) Ends ofdis-similarmaterials (e.g. Joists,beams, post griders; rafter:s, purlinstrusses, corbels steps etc.), upto500sq cmin cross-section.

(b) Opening upto O.1.sqrn

Note: In calculating area ,of openingsupto 0.1 sqm the size of opening shall

include the thickness of any separate lin- 5.4.12. Tolerances: Subject to the conditiontels or sills. No extra labour for fonning

that structural safety is not impaired and archi-such openings or voids shall be paid for.

tectural concept does not hamper, the tole macesin dimensions of RC.C. members shall be as(c)

The volume occupied by reinforcement specified in the drawings by the designer./

Whenever these are not specificed, the permis-(d)

The volume occupied by water pipes,sible tolemance shall be decided by the Engi-conduits etc. not exceeding 25 sq cm each neer-in-Charge after consulations With thein cro'ss sectional area. Nothing extra Designer, if necessary.shall be paid for leaving and finishing such cavities and holes.When tolerances in dimensions are permitted,

5.4.:U.5. Measurment shall be taken before

following procedure for measurements shall

any rendering is done in concrete members.

apply.

Measurement will not in9lude rendering. The

(a) " If the actual dimensions ofRC.e. mem-measurement of Re. e. work. between various

bers do not exceed or decrease the designunits shall be re&\llated as below:

dimensions of the members plus or minus

(a)

Slabs shall be taken as running continu-tolerance limit specified above, the de-

sign dimensions shall be taken for theously through except when slab is mono- purpose of measurements.lithic with the beam. In that case it will be

from the face to face of the beam.(b)If the actual dimensions exceed the de-

(b}

Beams shall be measured from faceto sign dimensions by more than the toler-

ance limit, the design dimensions onlyface of coulmns and shall include shaH be measured for the purpose ofhaunches, if any, between columns and payment.,beam. The depth of the beam shall be

from the bottom of slab to the bottom of(c)If the actual dimensions decrease more

beam ifbeam and slab are not monolithic. than the tolerance limit specified, theIn case ofmdnollthic construction where actual dimensions of the RCC membersslabs are integrally connected with beam,shall be taken for the purpose of measure-

the depth of beam shall be from the top of ment and payment.the slab to the bottom of beam.(d)

For acceptance of RCC members whose<'(c)

The columns measurement shall be takendimensions ·are not exactly as per design

through.dimensions, the decision of Engineer-in-

(d)

Chajjas alongwith its bearing on wallcharge shall be final. For the purpose of

I

payment, however, the clarification asshall be measured in cubic metre nearest given in para a, b & c above shall apply.to two places of decimal. When chajjas is combined with lintel, slab or beam, the

5.4.13. Rateprojecting portion shall be measured as chajjas, built in bearing shall be mea-

5.4.13.1. The rate includes the cost of materi-sured as per item ofliritel, slab or beam in

als and labour involved in all the operationswhich chajja bears.

described above except for the cost of centringand shuttering.(e)

\\-'here the band and lintels are of the same \!i

height and the band serves as lintel, the5.4.13.2. On the basis of mandatory lab tests,

portion of the band to be measured asin case of actual average compressive strength

lintel shall be for clear length of openingbeing less than specified strength but upto 70%

plus twice the over all'depth of band.

of specified strength, the rate payable shall be ,

90

in the same proportion as actual average com­pressive strength bears to the specified com­pressive strength.

Example:

1. Average compressive strength is 80% ofspecified strength. Rate payable shall be80% of agreement rate

2. In case average compressive strength isless than 70% of the specified strength,the work represented by the sample shallbe rejected.

3. However, on the basis ofmandatory fieldtests, where they prevail, the rates of thework represented by samples showingactual compressive strength less thanspecified strength shall be worked out asper para 5.4.10.5 (D-3) above. In addi­tion, Engineer-in-charge may order foraddition'al tests (see Appendix 'c' onpage 108) to be carried out at the cost ofcontractor to ascertain if the portion ofstructure where in concrete representedby the samples has been used, can beretained on the basis of these tests. Engi­neer-in-charge may take further remedialmeasures as necessary to retain the struc­ture at the risk and cost of the contractor.

5.4.13.3 Where throating or plaster drip ormoulding is not reuired·to be provided in RCCchajjas, deduction for not providing throating

- or plaster drip or moulding shall be made fromthe item ofR.e. e. in chajjas. The measurementfor deduction item shall be made in runningmetres correct to a cm of the edge of chajja.

5.4.13.4. No extra payment for richer mix

which projects into any member from anothermember during concreting of junctions of beamsarid columns etc. will be made except to the·extent structurally considered necessary andwhen so indicated in the structural drawings.The payments for work done under items ofdifferent mixes shall be limited strictly to what .is indicated in the structural drawings.

91

5.5 .. Encasing Rolled Steel Sections

5.5.1. Before concrete work is started, theEngineer-in-charge shall check that all rolledsteel sections to be encased, have been erected

truly in position. The sections shall be unpaintedand shall be wire brushed to remove the loose

rust/scales etc. Where so specificed,ungalvanised metal, having mesh or perfora­tions large enough to permit the free passage of12.5 mm nominal size aggregate through them,shall be wrapped round the section to be en­cased in concrete and paid for separately.

5.5.2. Wrapping

5.5.2.1. In case of columns, the wrapping shallbe alTanged as illustrated in Fig: 27 to passthrough the centre of the concrete covering.The wrapping of the entire length of the col­umns be carried out in stages and no stage shallcover more than 1.5 metre of height of col­umns. Successive wrappings shall be carriedout only afterthe immediate adjacent wrappinghas been encased in concrete. The surface and

edges of the flanges of the steel columns shallhave a concrete cover of not less than 50 mm.

The wrappings of successive stages shall ~tied together.

5.5.2.2. In the case of beams and grillages, thewire mesh or expanded metal shall be wrappedround the lower flange of the beam as illus-.trated in Fig 28 and the wrapping shall besuspended by wire hangers 5 mm diameterplaced at about 1.2 metres centres. The surfacesand edges of the steel sections shall have aconcrete cover ·of not less than 5Omm. The

wrapping shall pass through the centre of theconcrete covering at the edges and soffits of theflanges.

5.5.3. Form work shall be as prescribed in5.2

5.5.4. Concreting: Concrete shall consist ofa mix of 1:2:4 (1 cement: 2 coarse sand :4graded stone aggregate of 12.5 mm nominal

siz~) unless a richer mix is specified. The mixshall be poured solidly around the steel sec-

tions and around the wrapping by vibrating theconcrete into position. Consistency of con­crete, placing of concrete and its compaction,curing, finishing and strength of concrete shallbe as described in 5.4.

5.5.5. Measurements: The length shall bemeasured correct to one cm and other dimen­sions correct to 0.5 em. The cement concrete

shall be measured as per gross dimensions ofthe encasing exclusive of the thickness of plas­ter. No deduction shall be made for the volume

of steel sections, expanded metal, mesh or anyother reinforcement used therein. However, in

case of boxed stanchions or girders, the boxedportion only shall be deducted.

Fabric reinforcement such as expanded metalshall be measured separately in square metresstating the mesh and size of strands.

The description shall include the bending of the .fabric as necessary, Raking or circular cutting,and waste shall be included in the description.

5.5.6. Rate: The rate shall include the cost of

materials and labour required for all the opera­tions described above except the cost of fabric

reinforcement. The cost of providing and erect­ing steel section and wire hangers shall be paid·for separately.

5.6. PRECAST REINFORCED CON-CRETE

5.6.1. General requirements: Precast rein­forced concrete units such as columns. fencingposts, door and window frames, lintels, chajjas,copings, sills, shelves, slabs, louvers etc. shallbe of grade ormix as specified and cast in forms

ot moulds. The fonnsJmoulds shall be of fibreglass or of steel sections for better finish.Provision shall be made in the forms and

moulds to accommodate fixing devices such asnibs, clips, hooks, bolts and forming of notchesand holes. The contractor may precast the unitson a cement or steel platform which shall beadequately oiled provided the surface finish isof the same standard as obtained in the forms.

Each unit shall be cast in one operation.

·92

5.6.2. Concrete used for precasting the unitsshould be well proportioned, mixed, placedand thoroughly compacted by vibrations or

tamping to give. a dense concrete free fromvoids and honeycombing.

5.6.3. Precast articles shall have a dense sur­

face finish showing no coarse aggregate and

shall have no cracks or creyices likely to assistin disintegration of concrete or rusting of steelor other defects that would interfere with the

proper placing of the units. All angles of theprecast units with the exception of the anglesresulting from the splayed or chamfered facesshall be true right angles. The arises shall be'

clean and sharp except those specified or shownto be rounded. The wearing surface shall be

true to the lines. On being fractured, the interiorof the units should present a clean homoge­neous appearance.

5.6.4. The longitudinal reinforcemwtshallhave a minimum cover of 12 mm or twice the

diameter of the main bar, whichever is more,

unless otherwise directed ~in respect of all

. items except fencing posts or electric postswhere the minimum cover shall be 25 mm:

5.6.5. 'Curing

After having been cast in the mould or form the.

concrete shall be adequately prot\::cted duringsetting in the first stages of hardening fromshocks and frol1l,harmful effects of frost, sun­

shine, drying winds and cold. The concreteshall be cured at least for 7 days from the dateof casting.

5.6.6. The precast articles shall be matured

for 28 days before erection or being built in sothat the concrete shall have sufficient strengthto prevent damage to units when first hand1ed.

5.6.7. Marking :Pr~cast units shall be clearlymarked to indicate the top of. member and itslocation and orientation in the structure.

5.6.8. Precast units shall be stored, trans­

ported and placediil position in such a manner

that they will not be overstressed or damaged.

5.7 PRECAST CEMENT CONCRETEJALI

5.7.0. The jail shall be of cement concrete1:2:4 (1 cement :2 coarse sand: 4 stone aggre­gate 6 mm nominal size) reinforced with 1.6mm thick mild steel wire, unless otherwisespecified.

5.7.1 Fixing: Thejali shall be setin positiontrue to plumb and level before the joints sillsand soffits of the openings are plastered. It shallthen be properly grouted with cement mortar1:3 (lcement:3 coarse sand) and rechecked forlevels. Finally the jambs, sills and soffits shallbe plastered embedding the jali lmiformly onall sides.

5.7.2. Measurements The jail shall be mea­sured for its gross superficial area. The lengthand breadth shall be measured correct to a cm.The thickness shall not be less than that speci­fied.

5.7.3 Rate: The rate shall be inclusive of

materials and labour involved in all the opera­tions described above except plastering ofjambs, sills and soffits, which will be paid forunder rel~vant items of plastering.

5.8' DESIGN MIX CONCRETE

5.8.0 Definition: Design mix concrete is.that concrete in which the design of mix Le the

- determination ofpr<?portionsof cement, aggre­gate & water is arrived as to have target meanstrength for specified grade of concrete.

It will be designed based on the principlesgiven in I.S. 456-1978 and SP 23-1982" Hand­book for design mix concrete".

In order to ensure that not' more than the

specified proportion of test results are likely tofall'below the characteristic strength, the con·crete mix has to be designed 'forhigher averagecompressive strength and this higher averagecompressive strength for a specified grade ofconcr~te is defmed a target mean strength:

93

5.8.1. Materials:

5.8.1.1. Cement (:One of the following typesof Cement as sp¢cified shall be used:

1. Ordinary Portland Cement 33 gradeconforming to IS 269-1989.

2. Ordinary Portland Cement 43 gradeconforrriing to IS 8112-1987.

3. Ordinary Portland Cement 53 gradeconforming to IS 12269-1987.

4. Rapid hardening Portland Cement Con­forming to IS 8041-1990.

5. Blast Furnace slag cement conforming toIS 455-1989.

However for severe condition~ of sulphatecontent in sub soil water, special literature onuse of sulphate resisting cement may be re­ferred to. For supply and storage para 3.1.2.1.and 3.1.2.2. shall be applicable.

5.8.1.2 Coarse Aggregate

This shall be as specified in para 4.1.2 i/csubparas.

5.8.1.3.Fine Aggregate: This shall be ofgrading zone I, II or III as specified under para3.1.4 ilc sub paras.

5.8.1.4. Water: It shall conform to the require­ment as l~d down in IS 456-1978 para 4.3 andpara 5.1.1 of this chapter.

5.8.1.5. Grades of concrete

The compressive strength of various grades ofdesignation concrete shall be as given below:

M 15 10.015

M20

13.520

M25

17.025

M30

20.030

M35

23.535

Grades Designation Comprssive

strength on15cmCubes

min at 7 days

(N/mm2)

Specifiedcharacterstic

compressivestrength at28 days.

(N/mm2)

5.8.3.2. Minimum cement content required inReinforced cement concrete to ensure durabil­

ity under specified conditions of exposure, willbe in accordance with I.S. 456-1978. However

it shall nOtbe less than 300 Kgs/m 3 of concretefor 33 grade cement.

5.8.3.3. (a) Standard Deviation of concrete foreach grade shall depend upon the degree ofquality control expected to be excercised atsite. As per IS 10262-1982 the values of stan­dard deviation for various grades of concrete

for different degree of control shall be as speci­fied in table V.

Table V

Note:ln the designation of a concrete mix letter Mrefer to the mix and the number to the specifiedcharacterestic compressive strength of 15 cm- cubeat 28 days expressed in N/mm2•

5.8.2. Scope: The procedure described be­

low for design mix is for concrete upto grade

M-35 which are generally used for reinforcedconcrete structure. Minimum grade of concretefor design mix will be M 20 normally. How­ever in cases of projects having some parts of

M15 also in addition'to M 20 to M35 grade,then design mix concrete will cover M-15

grade as an exception only.

5~8.3. Data for Mix Design.: Tne following

basic data are required to' be specified fordesign of concrete mix.

Grade of Standard Deviation for different

degree of controlconcrete In N/mm2

Very GoodGoodFair

M15

2.53.54.5

M20

3.64.65.6

M25

4.35.36.3

M30

5.06.07.0

M35

5.76.77.7

(b) Degree of quality control expected underdifferent site conditions are described intable VI.

Very Good: Fresh cement from signle sourceand regular tests, weighbatchingof allmaterials, aggregates grad-

(1) Characteristic compressive strength ofconcrete at 28 days'.

(2) Degree of workability desired.

(3) Limitation on water cement ratio andminimum cement content to ensure ad­

equate durability.

(4) Type and maximum size of aggregate tobe used.

(5) Standard deviation of compressivestrength of concrete:

94

Degree ofcontrol

.Table VI

Condition of Production ofconcrete

Good:

ing and moisture content, controlof water added, frequent supervi­sion, regular workability andstrength tests and field labora­tory facilities.

Carefully stored cement and pe­riodic test, weighbatching of allmaterials, controlled water,

graded aggregate supplied, occa­sional grading and moisture tests,periodic check of workability andstrength, intermittem supervisionand experienced workers.

such case value oft will be 1.65 and

equation will reduce to Tck = fck+1.65 s

5.8.3.5. Selection of proportions

Since different cement, aggregate of differentmaximum size, grading surface texture shape,produce concrete of different compressivestrength for the same free water cement ratio,the relationship between strength and free wa­ter cement ratio con'esponding to 28 days'strength of cement of various grades is given inFig~l of IS 10262- 1982and is reporducedbelow in chart 1.

Pair: Proper storage of cement, vol-ume batching of all aggregatesallowing for bulking of sand,weighbatching of cement, watercontent controlled by inspectionof mix and occasional supervi­sion and tes~s.

5.8.3.4. Target strength for Mix Design: .

The target mean strength for a specified gradeof concrete depends upon the quality control(expressed by standard deviation) and acceptedproportion of results of the strength tests belowthe characteristic strength (Fck) and is given by

relation, Tck = fck + t.S

28 OA~ 5fREtlGTH a c.f'.)\EI-\T\E5T~t? ACCORDING TO "/

I. 5: 403) - \16 g,

A"" 3\ ''1- 3&" h tV1"M"'}-(?>2C;-375;:~ f

(..,l.)17.::. ~,,g-4/·7 rdJnJ?t(37!'_42'71'-~!CY

., C=41·H·(,·6 t1!-»>,,;'-(42S-41, t+J1c.Z)

9' "'<;.0- 5I,1jN/"""'Y47§-~25 "j/o.;'

!::0 S'I,$--Vb'4t-I/,.,,,,t72S--,75I(j';j,

f ==5'6,4-<::1:3 ~J..,",Y'i75-t.2' Y-J/0CHAJ'f f - RELATIDII &TweEt-)

o L J I I I I I I H<,\;~WATt::R..Ct'-!'\.fATIQ ANPo,3C> 0'35 O,4D bA? o,~o 0.55 0.'0 0.<:;; cow:.. 5WtNGT.f1 fOR.1:>lff[;-

WATt:1< CEI"ENT RATIO .RENT cj'Ot.I\. S\R.G~H1S.

(a) The free water cement ratio selected from

Chart 1 above should be checked againstthe limiting water cement ratio for re­quirement of durability as given in IS456-1978 and the lower of the two values

is to be adopted.Tck -

fck -

target mean compressive strength at

28 da~s

Characteristic compressive strengthat 28 days

(b) Estimate of Air Control

The amount of entrapped air for normal

mix (non air entrained) concrete a~per IS10262 - 1982 is given in table VII.

s - Standard Deviation

Table VIIt

Note:

a statistical figure depending uponthe accepted proportion of low testresults and number of tests.

According to IS 456-1978 & IS1343~ 1980 the characteristic

Strength is defined as that valuebelow which not more than 5% (1 in

20) results are expected to fall. In

95

Nominal miximum

size of Aggregate

10mm

20mm

40mm

Entrapped air as

precentage of volumeof concrete

3.0

2.0

1.0 '.:;

(c) Selection of water content and fine tototal aggregate ratio -Based on experi­ence, emperical relationship have beenestablished between quantity of water perunit volume of concrete and ratio of fine

aggregate to total aggregate by absolutevolume for desired workability. The esti­mated values for concrete upto M 35grade are given in table VIII.

Table vrn

Nominal Maximum size

Water content in kgsSand as % age of

of aggreate in mmper cubic metre oftotal aggregate by

concrete

absolute volume

10

20840

20

18635

40

16530

A) The values given in table VIII are based

on the following conditions:

i) Crushed coarse aggregate conform­

ingtolS 383-1970 and para 4. 1.2 ofthis specification.

ii) Fine aggregate consisting of naturalsand conforming to grading zone IIof IS 383-1970 and para 3.1.4 ofthis specifications.

iii) Water cement ratio (by mass) of 0.6and

iv) Workability corresponding to com­pacting factor of 0.8

B) For other conditions of workability, wa­ter cement ratio, grading of fine aggre­gate and for round aggregate, certainadjustment in quantities of mixing waterand fine to total aggregate ratio as givenin table VIII are to be made as per IS10262-1982. These are explained in TableIX below.

Change in conditionsstipulated for TabieVIII

Table IX

Adjustment required inwater content Percentage of fines to

total aggregate

(a) For sand conforming tograding Zone I & III ofIS 383-1970 o +1.5% for Zone I

-1.5% for Zone III

(b)

(c)

(d)

Increase or decrease in the value

of compacting factor by 0.1For increaseFor decrease

For each 0.05increase or decreasein free water - cement ratioFor increaseFor decrease

For rounded aggregates

+3.0%--3.0%

oo

-15 kg/m3

96

o

+ 1.0%-1.0%

-7%

C) Comparison of consistency measure­ment by various methods-

Workabilitydescription

Extremely dry

Very Stiff

Stiff

Stiff Plastic

Plastic

Flowing

Slumpmm

0-25

25-50

75-100

150-175

Compacting factor

0.70­

0.75

0.85

0.90

0.95

5.8.3.6 Calculation of aggregate Content

With the quantities of water and cement perunit volume of concrete and ratio of fine to total

aggregate content per unit volume of concreteto be calculated from the following equations

['C 1 fa]. v=[+ ~ + -;- x Sfax 1000

v=E+~+_l x~J x_ISc 1-P Sca 1000

c =

p

=

Sc

=

Fa,Ca =

v

w

=

1

absolute volume· of fresh concrete

which is equal to gross volume (m3)

minus the volume of entrapped air.

mass of water (kg) per m3 of con­crete

mass of cement (kg) per m3 of con­crete

ratio of fine aggregate to total ag­gregate by absolute volume

specific gravity of cement

aggregate (kg) per m3 of concreterespectively (total masses of fine

97

aggregate and coarse aggregate)

Sfa,Sca = Specific gravities· of saturated sur­face dry fine aggregate and coarseaggregate respectively.

5.8.3.7 Calculation of Batch Masses

The masses of various ingredients for concretefor design mix of a parti~ular batch size may becalculated as described above.

5.8.4 Production of controlled concrete

The calculated mix proportion shall be checkedby means oftrial batches. Quantities of materalsworked out in accordance with para 5.8.3.1 to5.8.3.6 described above shall be termed as trial

mix no. 1. The quantities of materials for eachtrial mix shall be sufficient for atleast three

150mm size cube concrete specimens and con­crete required to carry out workability testaccording to IS 1199-1959.

'5.8.4.1 Workability of Trial.Mix No.1 shall bemeasured. The mix shall be carefully observedfor freedom from segregation and bleeding andits finishing properties. If the measured work­ability of Trial Mix No. 1 is different from thestipulated value, the water content shall beadjusted according to Table X correspondingto the required change in compacting factor.

·With this adjustment in water content, the mixproportions shall be recalculated keeping thefree water-cement ratio at the preselected valuewhich will comprise Trial mix No.2. In addi­tion, two more Trial Mixes NO.3 and 4 shall bemade with the water content same as Trial Mix

No.2 and varying the free water cement ratio. by (+) 10 percent and (-) 10 percent of the

preselected value. Forthese two additional trialMixes No.3 and 4, the mix proportions are to berecalculated for the altered condition of free

water-cement ratio with suitable adjustmentsin accordance with Table X.

5.8.4.2 Fresh trial mixes are to be made for

different types and brands of cement, alternativesource of aggregates, maximum size and grad­ing of aggregates.

5.8.5 Batching

In proportioning concrete,the quantity of bothcement and aggregate should be determined bymass. Cement shall be used on the basis of

mass & should be weighed separately from theaggregate. Water should be etthermeasured byvolume in caliberated tanks or weighed. Anysolid admixture that may be added, may bemeasured by mass,liquid and paste admixtureby volume or mass. Batching plant where usedshould conform to IS 4925-1968. All measur­

ing equipment should be maintained in a cleanserviceable condition and their accuracy peri­odicall y checked.

Except where it can be shown to the satisfac­tion of Engineer -in-charge that supply of prop­erly graded aggregate ofunifonn quality can bemaintained over the period of work, the grad­ing of aggregate should be controlled by ob­taining the coarse aggregate in different sizesand blending them in the right proportionswhen required, the different sizes being stockedin separate stock piles. The material should bestock-piled for several hours preferably a daybefore use. The grading of coarse and fineaggregate should be checked as frequently aspossible, the frequency for a given job beingdetermined by Engineer- in -Charge to ensurethat the specified grading is maintained.

It is important to maintain the water-cementratio.constant at its correct value. To this end,determination of moisture contents in both fine

and coarse aggregate shall be made as fre­quently as possible, the frequency for a givenjob being determined by the Engineer -in­Charge according to weather conditions. Theamount of the water to be added shall be

adjusted to compensate for any observedvariations in the moisture contents. For the

determination of moisture content in the aggre­gates, I~ 2386 (part III) -1963 may be referredto.To allow for the variation in mass of aggre­gate due to variation in their moisture content, .suitable adjustments in the masses of aggre­gates shall also be made.!n the absence of exactdata, only in the case of nominal mixes,theamount of surface water may be estimated fromthe values given in the Table X.

Table X

Surface Water Carried by Aggregate(Clause 5.8.4.1)

Aggregate

Vey wet sand

Moderately_wet sandMoist sand

Moist gravel to crushedrock

approximate Quantity of Surface Water

percent by Mass 11m3

7.5 120

5.0

80

2.5

40

1.25-2.5

20-40

98

5.8.6 Mixing

Concrete shall be mixed in a mechanical mixer.

'The mixer should comply with IS 1791-1968.1tshall be fitted withhoppe.r. The mixing shall becontinuous until there is uniform distributionof the material & the mass is uniform in colour

and consistency. If there is segregation afterunloading from the mixer, the concrete should

be remixed. The mixing time shal,l not be lessthan 2 minutes.

5.8.7 Laying

It shall be done as specified under para 4. 2.4 ofthis specification.

5.8.8 Curing

It shall be done as specified under para 4.3.4 ofthis specification.

5.8.9 Approval of Design Mix

The preliminary test for approval of design mixshall consists ofthree sets of separate tests andeach set of test shall be conducted on six

specimens. Not more than one set of sixspecimem shall be made on any particular day.Of the six specimens of each set, three shall betested at seven days and remaining three at 28days. The preliminary tests at seven days areintended only to indicate the strength to beattained at 28 days.

5.8.10 Work Strength Test

tion of lots shall be determined by the follow­ing :-

1) No individual lot shall be more than 30m3in volume

2) Atleast one cube forming an item of thesample representiIig the lot shall be takenfrom the concrete of same grade and mixproportions cast in any day.

3) Different grades or mixes of concreteshall be divided into separate lots.

4) Concrete of a lot shall be used in the sameidentifiable unit of the structure.

5.8.11 Standard of Acceptance

a) The average strength of group of cubescast for each day shall not be less than thespecified work cube strength. 20 percentof cubes cast for each day may havevalues less than the specified strengthprovided that the lowest value is not lessthan 85% of the specified strength.

b) Concrete strength less than specified mayas a special case be accepted in a memberwith the approval of Engineer-in-chargeprovided that the maximum stress in themember under the maximum design liveload does not exceed the permissible safe

stress appropriate to the lower strength ofthe concrete.

Work strength test shall be conducted in accor­

dance with IS 516-1959 on random sampling.Each test shall be conducted on ten specimen,five of which shall be tested at 7 days andremaining five at 28 days. Not less than onework test consisting of tests on 10 cubes sh<!llbe carried out for every 30 cubic metre ofconcrete or less as per the lot size as specifiedbelow.

Lot Size

Concrete under acceptance shall be notionilllydivided into lots for the purpose of sampling,before commencement of work. The delimita-

99

c)

d)

e)

t)

Concrete which does not meet the strengthrequirements as specified but has astrength greater than that of the lowestvalue of 85% may, at the discretion of theI

designer, be accepted as being structur-ally adequate without further testing.

Concrete of each grade shall be assessedseparately.

Concrete shall be assessed daily for com­pliance.

Concrete is liable to be rejected if it isporous or honey combed, its placirlg hasbeen interrupted without providing a

a)

b)

c)

d)

e)

proper construction joint, the reinforce­ment has been displaced beyond the~tol­erances specified, or construction toler­ances have not seen met. However, thehardened concrete may be accepted aftercarrying out suitable remedial measures

to, the satisfaction of the Engineer-in­'charge.

Characteristic compressive 'strength requjred in the field at

f8 days

M~ximum sizes of aggregate

Degree of workability

Degree of quality cont,rol

'.Type of exposure

5.8.12 An example illustrating the mix de­sign for concrete mix M 20 grade is givenbelow.

5.8.12.1 Designstipulta,ion

20 N/mm2

20 MM (angularcrushed)

0.9 compactingfactor (slump75mm)

Good

Mild

5.8.12.2 Test Data of Material

a) Cement.used:- ordinary portland cement stisfying the requirements of Is 269-1989.

b) specific gravity of cement 3.15

c) Speciic gravity of

1)

2

Coarse aggregate

_Hne aggregate-(natural sand)

2.60

2.60

d) Water absorptiqn of

1)

2)

Coarse aggregate

Fine aggregate

0.5 percent

1.0 percent

e) Free Surface moisture of

1)

2)

Coarse aggregate

Fine aggregate

100

Nil (absorbed moisturealso nil)

2.0 percent

5.8.12.3 Sieve analysis

a) Co~se aggregate

IS sievesizesmm

20

10

4.75

2.36

Analaysis of coarse Percentage of different

aggregate fraciion

fraction

(percent pasing)

IITCombined

IIT 60%40%100%

100

100 6040100.

0

71.20 028.528.5

9.40

3.73.7

0

The sand confonns to grading zone III

The grading of combined fraction I & II in theratio of 60 & 40 conform to table, 1 describedabove.

5.8.12.4 Target mean strengt~ ;,;

As described earlier for degree of qualitycon-'trol 'good' the value of standard deviation is

,

b) Fine a~gregate

IS Sieve sizes

4.75

2.36 mm

1.18mm

600 micron

300 micron

150 mcicron

Fine aggregate (percent .r" .~

passing)

100

100

93

60

12

2

101

4.6, therefore with a tolerance factor of 1.65 the

value of target mean' strength for specifiedcharacteristic cube strength=20+ 1.65x4.6=27.6N/mm2 :

5.8.12.5 Selectionof water cement ratio

From chart 1, the free water cement ratio re­

quired for target mean strength of 27.6 N/mm2is 0.50. This is lower than the maximum value

.of 0.6~ presrcibed for mild exposure.

5.8.12.6 Selection of water and sandcontent

From table VIII for 20 mm nominal maximumsize aggregate and sand conforming to grading

zone II water content as per cum of concrete is

186 kg' and sand content percentage of tot~aggregate by absolute volume is equal to 35%.

For change in,value 'of water cement ratiocompacting factor, and sand belonging to zone

III the following adjustment is required.

+3' -3.5

Therefore the required water content =

186+186/100x3=186+3.58=191.6 kglm3 and

for increase in compactingfactor by (0.9-0.8)i.e.0.l0 +3 0

water=191.6 kgs

cement=191.6/0.5=383 kglm3

Thus Cement content is adequate ,for mildexposure condition as as per IS 456-1978 asdescribed in table below.

5.8.12.8 Determination of coarse and fine

aggregate content.

From table VII for specified maximum size ofaggregate of 20 mm, the amount of entrappedair in the wet concrete is 2 percent. Taking this

into account and applying equations given in'para 5.8.3.6

0.98 m3 = (191.6+38313.15+ 1/0.315. fa/2.60) x1/1000

and

-1.5

change in condition Adjustment required inwater content percentage inpercent total

aggregate'

for decrease in water

cement ratio by (0.6-0.5)i.e. 0.10 0 -2

for sand conforminggrading zone III 0

required sand content=35-3.5=31.5 percent

5.8.12.7 Determination of cement Content,0.98 m3= ( 191.6 + 383/3.15 + 1/0.685.ca/2.60) x1/1000

Water-Cement ratio = 0.5 or fa =546 kglm3 and ca=1187 kg/m3

The mix proportion now works out:

Water Cement Fine aggregate Coarse Aggregate

191.6

or 0.5

383 kg

1

546kg

1.42

1187 kg

3.0

a) Cement =50 kg ,

For 50 kg cement, the quantity of materials areworked out as below

c) Coarse Aggregate =154.5 kg

fraction I - 92.7fraction II - 61.8

b) Sand =71 kg

2) Extra quantity of water to be added forabsorption in case of coarse aggregate at0.5 % by mass=154.5/l00x0.5=0.77 kg

3) Quantity of water to be deducted for freemoisture In sand at 2% by mass=

(-) 171.0/100x2=(-) 1.42 kg

Therefore actual quantity of water =

d) water 25.00 +0.77-1.42=24.35 kg

1) For water cement ratio of 0.5 quantity=25.0 kg ./

Actual quantiy of sand required after allowingfor mass of free moisture =71.0+ 1.42=72.42

kg

102

Actual Quantity of Coarse Aggregate

Fraction I=92.7-(O.6xO.77)=92.24

Fraction II=61.8-(OAxO.77) =61.49

Therefore the actual quaL ?':: of differentconstituent required for mix are

Water=24.3;; kg

Cement=50 kg

Sand =72.42 kg,

Coarse aggregate Fraction 1=92.42 kgFraction H=61.49 kg

5.8.13 Measurements: shall be done is

accondance with Para 5.4.11 and its sub-paras

5.8.14 Tolerance: Para 5.4.12 shall apply.

5.8.15 Rate: Para 5.4.13 shall apply with theexception regarding limitations for actual aver­age compressive strength beingles than speci­fied strength which shall be governed by para5.8.11 for acceptance and proratat rates workedout accordingly.

5.9.0 Precast reinforced concrete door andwindow frames

5.9.1 Manufacture of precast reinforced con­

crete door and window frames is describes!here. These willconfonn to IS 6523: 1983inall

respects unless otherwise specified. Framesshall be manufactured in an approved factorywith all necessary - arrangements for fixinghinges or hinges fixed at position as specifiedwith hole for receiving tower bolt, sliding boltetc. as specified.

5.9.2 Shape and dimensions

5.9.2.1 Precast reinforced concrete door andwindow frames shall be 60 x 100 mm or 70

x75mm in cross section for single shutter and60x 120 mm for double shutter door, cross

section generally conforming to fig. 29 & 30.Where specified, suitable groo~e for receivingwall plaster shall be provided.

103,

5.9.2.2 The over all sizes (width and height)shall be as per drawing or as specified.

5.9.3 Materials

5.9.3.1 The materials used for manufacturingof the 'frames shall comply with standardsgiven in table I of IS 6523-1983

5.9.3.2 Aggregate

The aggregate used shalll be of well gradedmixture of clean coarse and nne aggregates.The nominal size of coarse aggregae shall notexceed 10 mm.

5.9.3.3 Concrete

Mix of concrete shall be as specified or asdirected by the Engineer-ill-Charge. But themix shall not be weaker than M 20 controlled

mix or 1:1 1/2:3 (1 cement: 11/2 coarse sand: 3,stone aggregate 10 mm nominal size by vol.mix) and shall be suitable for producing a denseconcrete without voids after proper vibration.

5.9.3.4 Reinforcement

There shall be a minimum of three bars of 6 mm

dia or equivalent as shown ?1 fig ..29 .. Thelongitudinal reinforcement for each vertical or

horizontal member shall be one piece and shallbe firmly held by 3 mm dia ties spaced at notmore than 300 mm centre to centre.

The longitudinal reinforcement shall have a,maximum cover of 12 mm or twice the diam­

eter of main bar, whichever is higher.

5.9.4 Casting

The entire frame may be cast complete in onepiece or each of the vertical and horizontal

members of the frame may be cast separately tobe assembeled into the complete frame at site.When the frame is cast in separate parts, one ofthe reinforcing bars of the vertical members of

the frame shall be kept projecting so as tote~on into the corresponding hole in the hori­zontal member. The holes in the horizontal

member for taking the projecting reinforce-

ment from the vertical members shall be sligtl ylarger than the bar diameter to faciliate easyinsertion of the projecting bar. Mter assembly

at site, the holes 'shall be grouted. with cementslurry of 1 cement : 2 coarse sand.

5.9.5 Mould

The mould for casting shall preferably be ofsteel to ensure better surface finish of the castframe. Provision shall be made inthe mould to

accomodate fixing devices for hinges and thehold fasts. Wh~re specified, suitable rebatesmay also be provided to act as plaster groove.

5.9.6 ,Protection & curing

After casting in moulds, during setting and infirst stage of hardening the concrete shall beprotected from shocks, running or surface wa­ter and the harmful effect of frost, sunshine<irving winds and cold. The concrete shall be•• _i- •

cured for atleast 7 days unless special curingmethods are adopted which shall conform to IS6523-1983.

The frames shall be matured before testing ordespatch for.the following periodS:

Type of cement used Period

Ordinary portland cement,portland blast furnace slag cementportland pozzolana cement 28 'days

Rapid hardening cement(to be usedwith approval 14 daysof Engineer~in- Incharge)

Theframes after maturing shall have sufficient

strengtll to prevent damage wh~n h<l!1dled.

5.9.7 Arrangem~nts for fi~ing of hinges toframes: Suitable ammgements forfi,xing hingesshall be provided in the frame by one of thefollowing methods as directed-(Ref. Figure30)

a) Hardwood fixture

Hardwood blocks of well seasoned teak

or other suitable timber 150 mm long, 45

104

to 50 mm x 30 to 40 mm in cross secti()l1,one block for each of the hinge, shall befixed in pOsition with 6 mm mild steelbolts, nuts and washers, after the framehas been cast, cured, and matured. Aftertightening the nuts, the bolt heads and thenuts shall be suitably covered with hardwood fillets, finished flush with concretesurfaces of the frame.

b) Hinge directly attached to frame. L Typeflap hinge may be attached directly to~fr<;unewith the help of 6 mm dia, mildsteel bolts & nuts.

c) Hinge welded to frame.

The hinge may be wel¢ed to 3 mp:1 thickmild steel flat embedded in a frame.

5.9.S Arrangements for Door and Win­dow Fixhlres

Suitable arrangements shaH be.PJovide9 in theframe for receiving tower bolts, sliding boltsand other door and window fixtures as indi­cated.

5.9.9 Fast.ners

5.9.9.1 Amangements for fixing the frameswith hold fasts or metalic fastners shall beprovided in vertical members \of ,frames asspecified. In case of door frame, there will be 3Nos. hold fasts and in case of window, therewill be 2 Nos. hold fasts on each verticalmembers in contact with the opening where theframe is to be fixed. Holes to accomodate 10mm dia bolts to be fixed to hold fasts and the

nuts shall be lei} at appropriate locations.

5.9.10. Erection.

5.9.10.1 Whena three piece frame is used,the vertical members shall be held in positionwith top member placed over them, the w~oleframe plumbed and firmly supported till theconcrete around the hold fasts in the masonryhas properly set and hardened. Cement and

, coarse sand mortar slumy 1:2 shall be used ~grouting the joints between the vertical andhorizontal members of door frame. In casewhere four members are used, the bottom mem- .ber shaH be first placed in position and othererected on this base.

APPENDIX - A

WORK TEST FOR CO~CRETE­MANDA TORY LAB TEST

(Clause 5.4.9.1)

, -

A-O One sample (consisting of six cubeslSx15x15 cm shall be taken for every

20cum or part thereof of concr,ete workignoring any part less than Scum or as

often as,considered ne,cessary by the En-'gL'1eer-in-Charg~. The test of concretecubes shall be carried out in accordance

with the procedure ~ described below. Aregister of cubes shall be maintained at 'the site of work in appendix D, .page110The casting of cubes, concrete usedfor cubes and all otherincidentalcharges,such as curing, carriage, to the testinglaboratory Shall be borne by the contrac­tors. The testing fee for the ~ubes, if any,shall be borne,by the department.

\

A-I Test procedure -

A-I.1 Mould'

The mould shall be of size 15 cm x 15 cmxIS for the maximum nominal size of

aggegate riot exceding40mm. For con­crete with aggregate size more than 40mm, size of mould shall be specified bythe Engineer-in-charge, keeping in view

th~ fact that the length of siz~ of !U0uldshould be about four times the size of

aggregate.

Th~ moulds for test specimens shall bemade of non-absorbent material and shall

be substantially strong enough to holdtheir form during the moulding of test'speciniens. They shall not very from thestandard- dimensions by more than onepercent. The moulds shall be so con­structed that tliere'is no leakage of water.from the test specimen during moulding. ­

All the cube mould~" for particular siteshould, prior to use, be checked for accu-

8-4/CPWD/ND/92:: 105

racy in dimensions 'and geomatric formand s~chJest should at least be made oncea year.

Each mould shall be provided with a baseplate having a plane sutface and made of

non absorbent rpaterial. ,This plate shallbe large enough in illameterto support themoulds properly without leakage. Glassplates not less than 6.5 mm thick or plainmetal not leSSthan 12 mm thick shall be

used for this purpose. A similar plate. shall be p~ovided for covering the topsurface of the test specimen when moul­ded.

NOTE: Satisfactory moulds can be made

from masJ:tYle or, steel castings.rolled metal plastes or galvanised .iron.

.. ,"}

A-1.2 Sample of concrete

Samples of concrete, for test specimenshall be taken at the tfnxer or in the case

.' of ready mixed concrete fr6~ the trans­portation vehicle discliarge or as directedby Engineer-in-charge. Such ~amples

shall be obtained by repeatedly passing ascoop or pail through the discharge stream

o(concrete. The saItJ.pliflg operationshould be spread over evenly to the entiredischarging operation/The sifuples thus

"obtained sha11.betransported to the placeof moulding of the specimen. To counter­act segregation, the concrete shall bemixed with a shovel until itis uniform in

appearance. The location in the work ofthe batch ofconcrety thus sarripled shallbe noted for further reference. In case of

paving concr,ete" samples shall ~ takenfrom the batch immediately after deposi­tion of the subgrade. At ~east five samplesshall be taken from different,portion ofthe pile an~ these",samplys shall be thor­oughly mixed before being used to f<?rmthe test specimen. 11u~"sampling shall bespread as everily as possible throught outthe day. When wide change$ occur during

"coi}cre1eshall'~<pl<}ced in mould.in twolayers, each approximately half the vol­um~,of the mould. fu placing e~chJcobp; ,'.ful of concrete the scoop shall be movedaround the· top edge of the mould as the

concret~ there ~1ides from it, in order toensure a symmetrical distribution of con­

crete wifu.i!1the mould. Either internal orextemalv~brators may be usedThe vibra­

tion ofeachl~yershallnot be continuedlonger than is pecessary' to ..secure' the

.- required density. Interiial vibrators 'shall

be of appropriate size and shallJ>enetrateonly the layer tore oompactedtIn com­p~ct.ipg th~ first layer~ the.vibrators shallnot be allowed to rest on the bottom of the

,..,.., .. , -.: .• ". c· ,

I1!0uld., IiIplacing the concrete for the top,:.q layer' the' mould shalH:>e·filled to the, - - ..

extent' that there willb~ no mortar loss

'during vibraq.on: A:ft:ervibratirig the sec­

ondlayerenough"co~crete shall be addedto bring level abOve the top of the mould.The surface 'Ofthe Concrete shall then be

;.; ,~--;.."

stI'Uckoff with a trowel and covered With

a glass or steel plate"as s~cified above.The whole process pf moulding shall be

ca,fIi~d out in such a m~er as t9 pre­clude the alteration of water-cement ratio

.. of the concrete by:loss of water, either by

c"'leakag~{from the",bot!0m. or over flowfrom the top of the mould."

«~ , ~_,,~":';t,.:f

A-1.~ Cut1ng,an4sioI:iig~.,of tesJ specimen

," In"'o;a;i'to 5~!1~~~-~~;;onably uniform

" tel!,lpe~tUre and ,m9ispl,re condipons dur­ing the first 24 hours for cU,r.ingthe speci­men and to protect them from damage,

/ moUldsshall be covered with wet straw or

~ ;guriny s'aJ19ng",,~fl placed in~ .~torage

bo~ so~nsti:uc~d3!ld kept on tl1e work>..site t4~~its airtem~rature ~tIen cbntain­

ing' concrete. specjmens' shall (Cmain

/l-2°'C ,to 33° C.. Ot:l]erc,suitapl~.nieanswhich provide s~~h a temperature and

,',moiswr(copditjons may ~used~

concretfug, 'addtional;mh.pies: shall be":taken if so desifed by; the Engineet-in­

charge.

A-1.3 :PreRaratlon of Test Specimens

The interior surfaces of the mould and

base plate shall be lightly oiled before theconcrete is placed fu the mould. The

samples of ~ncreteobtcpned'as describedunder the testspecimen shall be immedi­ately moulded by one of the followingmethOds-as iridicated below:-

- When thejob concrete is placed by vibra-.

tion aI!d the consistency of the concrete issuch fbat; the ".te§t specimens cannot be~- ..•. '.

properly ,lJloU1<ied, by"-handrodd!ng~as'

pesri!>esd 'aooye; ~~'specimens shall bevibraied to give aeompaction correspond­ing.to that of the joMzoncrete. The fresh

,--,-

When the job concrete is compacted bymanual metbogs; the test specimen shanbe moulded 1;>YI>lacing,thefresh~ncrete .in the mould in three layers, ,each. ap­proxiffiately one t!U[d of the volume of ~·the mould. In plac~g each' scoopful of.concrete the scoop shall be moved around

the top edge of the It1.ouldas the concretethere slides from i~, inordedo ensure a.uniform distribution of concrete,;within

,the moUld~>Eachlayer shall be rOdded 35,tiffie~With "i 6mm rod, 60 cm in length,bullet pointed at the lower end. The strokesshall;c~ j1iStrib~~~ iP.,uniform:'matmer

- ~-,.:~~ ..~"'-; / '--' .,;-- ...,~- - ~, " over the cfus'"ssection of the mould and.

·"shallperterate irltojmderlying.layer ..The,bOttomlayershall.be fOdded throughout~ ..•.. i:~.' ;-' ,,' . ,. ". ',>, - "'

i!Sd~p~YAfter the t§p Jayer'has ~n>--. ~- - ..•• -~".- ,!,,~~, -'-,' "''''''''' .. '

rodded, the surface of the concrete shall

be,struck ~off'Yith a jrowerand coveredwiih a glass plate at leas(6~5 nun thick or

a machin~' plate. We wholeTprocess,ofrllouldfug shall be cMried outin sheh ama

;,nnet as £<1' p@Clud~ the.:ch,8I!ge of the

~,,water cement ratio ofth~ cd~crete,by loss'of~ater either By ie#!lgefw!Il'tfie bot­tom;to? o~ei'flbwfrom ,the t6pibf the

,';"~iDofua~~~<',~, ~., ,~;.,.,.~

" 106

A-1.5 Te,sting

"The specin?-~nsshall6e"tested in~accor­dance with' piqsedure as"described be-low: "

"-

with battens to avoidwatping. The

.box should=be well painted ;nm.de:.and outside,and should be prPvided~with a hirtged cOverand padl~k.

The t,est,spegmen shall be ~mdv¥ from'the moulds at the. end of 24 hours and

_,", stored ill a moist,condition at a tempera­ture within 24°· cto 300 c until the:timeoftest. If. storage, in water is desired, asaturated lime solution shall be used.

a) TIu~tests shall ~ made. at ~ age o( .'concr~~eccorrCSI'2IldiIig..,to'tJIat forwhich the stre,ngtl,ts"ajes~cified;

b)' , Comp~ssion tests shan 00. made. i1!1mediately,uponremoval' of the

concrete test s~en f~ the.curing rOOlnte. the test spCcimen

shall ~ loaded !P'd~p condition.The <fil!1ensio~()f ~e ~st,speci­m~ns ~hallbe ni~asu~d in mm ac­curate)o 0.5 mm.

APPENDIX B

(Clause $,.5.9.1)" -~ &

B-1 REBOuND HAMMER TEST.,:

~ANbATORYnELDTES~•. ,,,_, ,.. ., -c. ':- ~ ~_.:.~ _ ._,_

If a rebound hammer.~is reght8rty used. bytrairle<lperSgnnelin accordai1cewith proce­dure desribci1in IS 13311 (part II) -1992 and acOntinuouslymamtained iD.dividualcharts arekept showing a large number otrea~gs and ­the relation ,betWeenthe readings and strengthof cOncretecubeSmadef1'Om the same batch ofconcrete, such charts may be used in Conjunc­tion with hammer' readings to obtain ~ ap.­

proximate indicatioo:of the ~~ of COn­

crete dn a structure or element. I.f~alj.bratiollcharts are available frotn manufactUrers,it ca,I,1

be used;~When ma1dn~,.rebound ~mer testSeach result shouJ4be th~av~rage of at least 12readings. ReadiDgsshpu!d not be t,*en within20 mm of the edge o! concrete mem~rs and itmay ~ neacessarytodistingUish between read­ings iaken,on a trowel¢, Jace and those on amoulded~'face;,tWhen making thetest~ on aprecast units, special ;care should,be taken tobed~th~m finnlyagairist the impact of thehammer:'- .

, d) The load ~ be _applied 'axiallywitout shoc~ atJhe rate of approxi­mately 140 kg.sq em per minute.The total load indicated by the test­ing machiiie at failure of test.sped':men sh,allbe recorded and the writcOmpressive strength.is calculatedin kg per sq em using the area com­puted from the meitsured dimen­sions of the test specimen. The typeof ~failure and appear.ance of theconcrete shall be noted

The me,talbea~g plate~~fthe Jest­iI!gmachi.Qesnall be placed ~&'n~tact~th t!J:eends of t!J.etest specj-

-~ ....•. ""':0: -.' " • .,..,.- ',- -- ..•.

inenS,'Cushonmgmaterialsshallnot ,.~ .. _. -'~, _.~ 'S .1 :

be used. Inthe case of cu):?es,thetest~ -;;. • ': .'" .. , ",c"';;

,'s~(;i.m~!lsh.@"be placed mthe. machinem S\i'Cldi ttIanner that the

",~__ ;,.- lr-",. -,.-:' ~»

IQadis apj>liedtosid~s of the s~ci-~'OC,' , ','-: ..• ':..1' ~_~-!. ,~_

.mens as cast; An adjustable bearing- .. C';;'.- .,'*'.;- .;: -;;:.,_ n •• ~ ,""

, block shall"be.used)o:trarismit the"- ":;, ••_'f.;.~,, ,:.."- ,- .c-' :_~

load to the test specimen. The sizeof thebearingbl~ok shaIl.~bethe

·same.or,slight!Y·I~rgerJhai1that oftest sPecimen. The upper or lower'- .~:<-~;j::- '," -" -~'" .~ ,~

,section of the bearingq~O(;kshallbek~pLin moti()n'asJh~:hea~,ofth~.testingma,£hineis6!oughtt~ ~beai~ing on the test specimen.

c)

107

APPENDIX-C

ADDITIONAL TESTS FORCONCRETE

(Clause 5.4.9.2)

c-o In case th~ concrete fails when tested as

per the method presribed in Appendix A,

one or more of the foll~iwing check testsmay be carried out at the discretion ofEngineer-in-charge to satisfy the strengthof the concrete laid. All testing expendi­ture shall be borne by the contractor. Thenuinber of additional tests to be carried

out shall be determined by the Engineer­in-charge. He shall be the fip.al authorityfor interpreting the results of additionaltests and shall decid~ upon the accep­tance or otherwise. His decision in this

regard shall be final and binding. For thepurpose of payment, the Hammering testresults only shall be the criteria. Some ofthe tests are outlined below:-

-C-l '.CUTTING CORES -

This method involves drilling and testingcores from the concrete for determination

of compressive strength. In suitable cir­cumstances' the compressive strength ofthe concrete in the structure may be

assessed by drilling cores from the con­crete and testing. The procedure used

shall comply with the requirements ofIS1199-1959 and IS 516-1959.

The points from which cores shall .betaken shall be representative of the wholeconcrete and at least three cores shall be

obtained and tested. If the average of thestrength of all cores cut from the structureis less than the specified strength, theconcrete represented by the cores shall beliable to rejection and shall be rejected ifa static load test (c-4) either cannot becarried out or is not permitted by theEngineer-in-charge.

C-2 ULTRASONIC TEST

If an ultrasonic apparatus is· regularlyused by tniined personnel in accordancewith IS 13311(part I) -1992 and'continuosly maintained individual chartsare Kept showing a large number of read­ings & the relation between the readingand strength of cubes made from the samebatch of concrete, such c!1arts may beused to obtain approximate indications ofthe strength of concrete in the structures.

'In cases of suspected lack of compactionor low cube strength the results obtained

from the ultrasonic test results on adja~cent acceptable sections of the structuresmay be used for the purpose of assessingthe strength of concrete in the suspectedportion.

. C-3 LOAD TESTS ON INDIVIDUAL PRE­CAST UNITS

The load tests described in this clause are

intended as check on the quality of theunits and should not be used as substitute

for normal design procedures. / Wheremembers require special testing, such

spe~ial testing procedures shall be in ac­cordance with the specification. Testloadsshall be applied and removedincremently.

C-3.1 Non-destructive Tests

The unit sha}1be supported atits designedpoints of support and loaded for fiveminutes with a load equal to the sum ofthe·characteristic dead load plus one anda quarter time the characteristic imposedload. The defleaction is th~n recorded.

The maxinium deflection after applica­tion of the load shall be in accordance

with the requirements defined by the En­gineer-in-charge. The recovery is mea­sured .five minutes after the removal of

the load and the load then r.eimposed: The

percentage recovery after the second load­ing shall be not less than that after the firstloading nor less than 90% of the deflec­tion recorded during the second loading.

108

--At notime during the tests, shall the unitshow any 'sign of weakness or faultyconstruction as defined by the Engineer­in-charge in the light of reasonable inter­pretation of relevant data.

C-3.2 Destructive Tests

.. ,The unit is40aded while supporfed at itsdesign poiilt of support and must not fail

at its design load for collapse, wi~ 15minutes of time when the test load

beacomes operative. A deflection e)(ceed­ing· 1/40 of the test span is regarded asfailure of the unit. /

·C-3.3 Special Tests

For very large units or units not readily

amenable to the above test e.g. colUIims~the precast parts of composite beams andmembers designed for continuity or fix­ity, the testing arrangement shall be agreedupon before such units are cast.

C-4 LOAD TESTS OF STRUCfURES ORPARTS OF STRUCTURES

When the limit state of collapse is beingconsidered the test load'shall be equal tothe sum of characteristic dead load plus

. one and a quarter times the characteristicimposed load and shall be maintained fora period of 24 hours. In any of the testtemporary supports of sufficient strengthto take the whole load shall be placed inposition underneath but not in contactwith the member being tested. Sufficientprecautions must be taken to safeguardpersons in the vicinity of the structure.

C-4.3 Measurements during Tests

Measurements of deflection and crack

width shall be taken imme~ately afterapplication of the load and, in the case of24h sustained load test, at the end of 24hloaded period, after removal of the loadand after 24h recovery period. Sufficientmeasurements shall be taken to enableside effects to be taken in account. Tem-­

perature and weather contitions shall berecorded during the tests.

C-4.4 Assessm~nt of Results

In assessing the strength of a structure ora part of the structure following a loadingtest, the possible effects of variation intemperature and humuditi during theperiod of the test shall be considered.

The following requirements shall be met:

The test described in this clause are in­tended as a check where there is a doubt

regarding structural strength. Test loadsare to be applied and removedincremently.

C-4.l Age at Tests

The test is to be carried Fissoon as pos­sible after the expiry of 28 days from the

time of placing of the concrete., When thetest is for a reason other than the qualityof concrete in the structure being in doubt,the test may be carried out earlier, pro~vided that the· concrete has alreadyreached its specified characteristicstrength.,

C-4.2 Test Load

The test loads to be applied for the limitstates of deflection and local damage are.the appropriate design loads i.e. the char-acteristic dead and superimposed loadS.

109

a)

b)

The maximum width of any crackmeasured immediately on applica­tion of the test load for local dam­

age, is to be not more than 213 of thevalue of the"'approriate limit staterequirement·

..,

Formembers spanning between twosupports the deflection measuredimmediately on application of the

.test lo~d for deflectioI} is ~obe notmore than 1/500 of the effective

span. Limits shall be agreeed upon

before testing cantilevered po~onsof structUres.

c)

d)

If, maximum deflection 5' in mm

s~own~uring 24 h .under load isleSs than 40L2/D where L is effec­

tive span in ill~ D is 9verall depthofconstruciioo in. rom, ~t is not~ssary for the recovery to be'

" me<1Sin-ed and the require~ent (d)does not apply, and

If within 24 hours of the'removal of,.,- ~

test' load Jor collapse as calculated

in ~lause (a) a reinforced concretestructure does not show a recovery

of at least 75 percent of the maxi­t;num deflection 'showndUrlng the24 h under l()~d, the loading shouldbe repeated. The structure should beconsidered to have failed to pass thetest if the recovery after second load­ing is not atleast75 percent of themaximum deflection shown during,the second loading.-

APPENDIX-D"REGISTER OF WORK TEST OF CONCRETE

. (Clause A-O of appendix A)

a)

b)

c)

d)

e)

t)

g)

h)

Name of work,

Name of contractor

: Agreement No

Sample No.

Identification mark

Portion of work and quantityrepresented by sample

Date and time of c'asting ,cube

" Proportion of mi.x

Concrete mix,(By volume) .'

1:1:2

1:1 1/2:3

1:2:4

Compn;ssive strength, in kg/cm2 on 7 days

210

175

140

1. "Due date of test

7Days' Test (C!. 5.4.10.3.)

cube No.

2. " Actual,date of test

3. ~ MfuIDmumstre~~

b) Maxinium Strength•c) Average strength of three cubes

d) ,Difference between 3 a & 3b

~ e) Difference in % age in tepns pf average strength -

i.e 3b-3a

--,- .... x 100 =3c

. 110

,4. ~Pecified compresssive strength of concrete mix used -

ii)

'5 a) If 3 (e) is more than 30%

b) If 3 (e) is equal to or lessthan 30% than proceede as below:

i) Difference between column 4i.e. specified compo strength &column 3 (c) i.e. actual average ishigher, it will be denoted(+) and (-) if it is less.

Difference in Column ~ (b) (i) in ., terms' of % age of specified strength

Sample is not acceptable, then 28 days'

,strength test shall be carried out. '

3(c)-(4) x 100%4

ill) If the difference in col5 (b) ,(i) is+ve and the'same in terms of % age,of specified strength (4) i,e. value of ,co1. 5 (b) (ii) is with in (+ 15% range)

JE

Acceptable & Strength isconsidered in order /'

.AE/AEE ' BE

b) Name of contractor

c)

Agreement No

d)

Sample No.

e)

Identification mark

f)

Portion of work and quantityrepresented by sample

g)

Date and time of casting cube

h)

Proportion of mi,x

, a) Name of work

REGISTER OF WORK TEST OF CONC,RETE

Concrete Mix

(by volume)

1:1:2

1:1 1/2:3,

1:2:4

compressive strength. in kg/cm on 28 days

315

265

210

1. Due date of test

28 Days' Test (C!. 5.4.10.4)

Cube No.-

2. Actual date of test

3. Actualcomp. strength of cubes. (MiD No. of cubes to be tested-tl1reC)

-111 - .

a) Minimum Strength

b) _Maximum Strength

c) Average Strength of three cubes

d) Specified compressive strength of concrete mix used

e) 70% of specified strength

f) 130% of spcified strength

4. If 3 (b) = 3(f) and 3(a) ~3(e)

5

If 3(c) is more thai13 (f)

6.

If any test value exceeds 3 (f)

7.

If 3 (c) ~ 3(d) but < 3 (f)

8.

If 3 (c) < 3(d) and> 3 (e)

9.

If 3 (c) < 3(e)-

112

Le. 10% of 3 (d)_.~- -- - .. - ­--' ._. --" ~._-.. --' --~~'-- . --.,

i.e. 130% of3(d)

value of3 (c) shall be compressive streIigthof sample.

tm mayor~er further investigation

It should be restricted to 3(1) for computa­1ion of strength.

Strength is in oider and concrete acceptedat full rates.

Concrete may be accepted at reduced ratesin accordance with para 5.4.13.2

Worle represented by this sample shall berejected and action taken as prescribed inclause 5.4.1004

SET UP OF STEELFORM WORK

TYPICALWALL

FIG. 1A

..'

CHAPTER - R.C.C.(FORM WORK)

CLAUSE - 5'2,], 6FIGURE - 1.

.

. .. "

o ",

-

SINGLE SJDED WALL FORM (ADJUSTABLE)'

:'0' .0' •..'...

~.. :"!'

..',.,..

...

----

All members' are of 5 t eel.

,FIG.-1 BDOUBLE SIDED' WAll FORM

. 1~

WALL FORM..CHAP TER-RoC. C.

(FORM WORK 1CLAU SE ~ 5,·2-9·6·FIG UR E - 2 .

CLIPS

ADJUSTABLE CURVED WALL FORM (DOUBLE ,SIDED 1

FIG.,-2'All MEMBERS ARE OF STEEL.

I ­I

114

75 LONG~e.0LT ~:_,-.1 - •....

WASHER -

FI~fINGDE,TA IbSTIES

TV F?~ICAL- - elF

SOLDIER -

WA=LL

COILJIE

lEN6! ~CONES

- CHAPTER - R.C.C.

(FORM WORK)

CLAUSE -5'2-3 .. ' 2

FI GURE - 3 .

WALL TIE' FOR TWO SIDED SHtJ,TTERING

ALL MEM BERS ARE OF STEEL

WALL TUBES

- CHAN NE L SOULDIER 2· 5M: LONGWALl FORM PANELS

C ••1750"­

0"1125E"1250F_"137S,'~,,:2t5pO_

100

..

..

•...:

I .".

..

EL EVATiON

A-ASSEM8.LY-CLIP

B-,~RIDGE. cLIPs- SINGL£ cLIP

U1-['--,..--

~OSITION' OF WALL TIES &- WALING TU8tS

(SMUTTERING FOR 1ST POUR Sf:lOULD 8E •~ ;". - t "'- .~,' .••.•

PRORERLY STRUT-TED BY RAKERS)

,c~~t;,:;,EG~~I ~(;OA~~~~~ ~ F:IG.!3 ~fiJ115 ~- "-~.- .. "-..,.,. -.,

'!:"" -- "

(CENTRING 8; SHUTTERING). Cl A US E - 5. 2 . 3FIG - I..

TYPICAL STANDAR[) UNITSFORM WORK

DETAilS AT 0

OF

"§III§

DETAilS OF H FRAME UNIT

JI~I,B

90Ft 9f II0. III

1'12

0

C>oC>

U'I, U-Lt '+ 0f-3 M ,2 M 2·I.M 1·2 M

E - VERTICAL S

(IN DIFFERENT HEIGHT!)

ADJ. STIRRUP HEAD

D

FIG.-'116

I

IJ d\ + KNOCK TOI=";-----!-. t ';==:1 DROP'J"",-_- _1 l...! ,'

DROP HEADC

ALL MEMBERS ARE OFS TEEl

AL,~ DIMEN SrONS ARE IN /M tv!

DRAWING NOT TO SCALE

TYPICAL COM~ONENTS OFFORM WO~·K

CI=tAPTER - R.C.C.

(FORM WORK)CLAUSE-5'2')'2FIGURE-5

DIAGONAL

B

TU8ULARTRANSOMILEDGER/HANDRAIL

A

'\

ANG LE TRA NSOME. \

o II. I:dI ~IF

SCAFFOLD BOARD

.~. -1-"~~/"~I L FiXED SASE PLATE.~~ .I, '::::--::;;;~, .

GII

'.H

.SPIGOT ·LOCK

I I CUP LOCK1 I.COLLAR- GRIP

HOP-UP 8RACKET ANGL E TIE AD JUSTARLE. BASE

i;.

TYPICAL ARRANGEMEN'TCOLUMN FORM ,WORK CHAPTER.;. Re.C.C.

(FORM - WORK)CLA'u SE - 5·2·3·2FIG. '- 6.

ICORNER ANGLE BRACKET

" .,• I;

FOUR SIDES ADJU 5 TABLE COLUMN, FORM

'CORNER ANGLEBRACKET

TWO

ALL 'MEMBERS ARE"6F STEEL118

EXTERNAL CORNER ANGLE'

. FORM-;"~'"

. CHAPTER -R.C.C.

(FORM WORK)

CLAUSE - 5,2,,),2FIGURE - 7.

TYPI CAL COLUMN SHUTTERIN9

FIG. - 7

ALL MEMBERS ARE OF STEEL

DETAIL ,;OF BEAMSTIFFNER

TYPICALHEAD AND

I£AM HEAD 0

ASSEMBLY OF BEAM

HEAD OVER PROP

BEAM HEAD CD

CHAPTER - R .C.C.

(FORM WORK)FIGURE - 8.CLAUSE - 5·2·3·3

~

l 5 TIFFN ER

1 VARYJ~ WIDTH t'- ~ J~MM

~MM S TIFFNER

FLOOR FORMS(OUT OF 14 GAUGE M.S.SHEET)

(A DJUS TER FLOOR FORMS

AVAILABLE .IN VARDUS SIZES)

®

ALL MEMBERS ARE OF STEEL.

PLAN OF FLOOR (SLAB) FORMS

®

FIGURE ..,8120

TYPICAL DETAILS OF MULTI.STAGE SHUTTERING

SUSPENDED FLOOR/.iSlAB TO

.·········m---·-- ~----.-.

STEELSHUTT CENTR-. ERING -IN G---- - - - - - - -- - -

- -- - - ------- - - -

./o.lSBEAM ­

HEAD

PRO P5

VERT IC

BE CAS T...,

-r HEIGHT ~ 3.5 Nt

1

tEIGHT'\< 3.5 M

CHAPTER - R .C.C:(FORM WORK)

CLAUSE - 5·2'3·2FIG. - 9.

SUSPENDED FLOOR -MULTI STAGE SHUTTERING

( VERTICA L SECTION)

FIG.-9AA LL MEMBERS ARE OF STEEL

121

9-4!CPWDIND/92

VERTICALS

-·DIGONAlS

\\

DETAILS OF EXPAN'SI0N JOINTS( INVAAIOUS lOCATIONS) CHAPTER - R.C.C.

CLAUSE- 5,',5F! G U R E - 10 &11.

JOINTS

•• 'Ot' •••• 4 ,

GROOVE AT'R.C.C.-MASONRY JUNCTION

FIG..-10 EXPANSION JOINTS IN lONG SUN SHADE

R.C.C. COPING'

CRAFT PAPE.R OR'BITUMEN PAINTlNG­

BRICK TILE

BITUMEN FlllE R

R .C.C. BEAM

A. C. SHEET

BITUMEN PAIN TIN G

rLi ME TERRACING I MUD PHUSKA

·C£.lING PLASTERR.¢~~.;SLAa _',M ET',1!iiiCRA OLE'''''.0;,;;/.'.' .:-""

-RAWl' PLUG & SCR''EWS'WITH OVALSHAPEP SLOT & WASHER

'RAWL PlU G & SCREWS

DE TAl LS OF RAISED TYPE EXPANSION JOINT AT ROOF

FIG ... 11122

EXPANSION JOINTS (C ONTO.)CHAPTER .R.C.C.

, CLAUSE - 5-4,5FIGURE -12 T014.

A.C. SHEET

RAWl PLUG & SCREWS-

FIG; 12 TYPICAL DETAilS

If:

25M~,1 THICI< TO MATCH& LAID OVER A .cOAT

FILLED WITH J GIN T FILLER

R.C.C .SL AB

METAL CRADLE FILLED UP

"'.'.IL~_~ITH BI TUM EN FI LLEH ( ABOVE)- . ~PLASTER-.:' R .C C. BEAM

-RAWl PLUGS &. SCREWS WITHOVAL SHAPP EO SLOT & WASH ER

~R.C.c. PRECAS T .TIl.£

.THE FLOOR FINISHOF HOT BITUMtN

:..1---,--,-12 MM (,.AP.•..

',8 .•

25M M GAP

c.c.

R .C.C. SL.h. BBIT UMEN FI LLERMETAL CRADLE

R.C.C. BE.6.M

FIG 14 ---,.." 25 M~~ GAP...• TYPICAL DETAILS OF ·EXPANSION JOINT

AT ROOF t FLOOR JUNCTION

123

MASONRY TO BE CONSTRUCTEDAFT ER PLACINGCANTILE VER SL A B

.. IC.C .GOLA -

\\

BRICK WALLPLASTER

R.C.C. CANTILEVER SLABD~BEDoED IN MASONRY ATONE END, FREE AT THE OTHER END

FLOOR FINISH SKIRTING.MUD PHUSKA

EXPAN SION JOIN TS (CaNTO.)

A. TWIN\BEAM WITH TWIN COLUMNS

Twin beams

CHAPTER - R. C.C.

CLAUSE - 5, 4·5

FI G UR [ - 15 TO 18

[ - - -f -- -- ---- -- --- - -- -- -c--J•.-- - - -' - -- - -- - - - - - - - - .•. ---

Twincol umns

t'50 Copper Dcradlt for'beam

o

External lace

IA.J

PLAN

Twin beams Twin columns

tiliJ~<.'..'. ~':"::~. C· ··E·.·," . :

D-¥.25SEC A-A ON ROOF

LENGTH

inlermediate expansion joint)

Q1,P2~ tGap 12SECTION A-A ON flOOR

B. SLAB & T:BEAM CONSTRUCTION OF

( T- Beam changed inlo rectangular beam 10

5mm •• pans! onjoint fill.dwith bit umenI iller

-=!. .. Flooring

J.R.c.c. Slab.. ~::..;.. '

.~.

.-A : lM~dfuska8'~ : ....•. I laid 10 sl

.' .. ,. ". <:pe

::.,.;~ R.C.C.',b.• :/:1~ _. " R.C.C. Beam

Plast er

."T- 8 ea m

LONG

prav ide

FIG.-15

f

Unfilled gap

R.C.C. Rectang.\ .•· :":.-ular beam '. '.

L1QQ

12 mm open joint infloor stagger e d fromupansion joint filledwit" bitumen

Situmen lelt

12mm expansion joint jfilled with bitu men Iilleror impregnated fibre board

FIG. - 16

C: LONe; VERAN DAH SLAB

ll2006-13OOO t 12000-13000 }1 • 12

KEY PLAN

D. LONG WATER -RESERVOIR SLABo-~2

PLAN

FIG. - 17Butl joinli.floor & slab

~ $Fborin~

.~.. -.. : ':'.;.'.:': R.C.C. Sab

Bilumen lelt ..... ' ..• Ceiling plaslerPART SEC. A- A

FIG.-18

r~":·:-·.~:....:~~.'.~:':-':::~':'~j~arln lilling'" .' . ' •. ~ : ...•• R.C.C. Slab.. " ....•..... Plaster 6mmSECTION A-A

A' Hot bitumen painting @ 1·7 k.g./ sqm.BBifumen filler.CRawl plugs t, 50mm screws @ 300 mmclc.D Asbestos sheet 150mm wide or P. V.C. sheet.

E Rawl plugs & scr'ews with oval shaped slot•• washers @ 300 mm c/c.

F Copper cradle. 124Drawing not to scale.All dimensions ar e in mm.

EX PANS10N JOINTS (CONTO.)CHAPTER - R .C.C.

CLAUSE - 5'4,5

Ft GURE - 1CJ TO 22 .

TYPICAL DE TAl L OF EX PANSION JOIN 1. COVERING

ON OUTER FACE OF C OLU MN S (PL AN)

R AWL PLUG .& SCREW W ITIIOVAL SHAPPED SLOT &, WASHER

12 MM GA P

INSIDE

FIG. _19PLASTER

-200 M MASSES TOS CEMEN T FLA TSHEET OR ALUMINIUM PLATEOR SIMILAR MATERIAL

RAWL PLUG & SCREW

R. C .C . COLUM N25 MM GAP

STEEL OR AlUMIr'JIUM ANGLEFIXEO WfTHRAWL PLUG &,

SO MM SCREW Ia) 300 MM ~Ic..:\\12MM GAP \:,

FIG.2QTYP'CAL DETAILS OF

EXPANSION JOINTS.~TCORNER COLUMN

REINFORCE

BRICKWORK

PlAS TER

25MM GAP

•.••

•..

R.C.C. COLUMN

PV.C.WATER

S Tor! BAR

EX PAND EXBOARD

JG COMPOUND

JOINT FILLER

FIG. 21

-..

-

,~ • .J,

. ~.':.,

,...t-...; .., '.

'- c.t:" 1\ I

COLUM N

TYPICAL DETAILS Of EXPANSION

JOINT ~T ISOLATED TWIN COLUMNS

JOINT FILLERDISCONTfNUTY'lN BOTH'CONCRETE' & STEEL

EXPANSION JOINT SUBJECTED

TO WATER PRESSURE

(FOR WATER TANK S )

FIG.22

.•. - " ........•

125

EXPANSION JOINTS ( CONTD~)@ 12MM E)(~ANSION JOINTS FILLE.D WITH BITUMEN

FILLER ORIMPREGNATEDR8RE BOARD·

(96MM CEMENT PLASTER 1!J (1C;:3F. SAND) FINISHEDWITH A FLOATING COAT OF NEAT CEMENT AND ATHICK COA.T OF LIME WASH OR LAID WITH KRAFT PAPER.

CHAPTER - R.C.t.CLAUSE - 5·4,5FIGURE - 23 .

D. INTERMEDIATE WALL WITH FLOOR SLAB

50 TO100 UNFILLED ,/BUTT JOINT IN THEGAP AT TOP. / FLOOR STAGGERED 'FROM EXPANSION JOINTS

<-

C. END WALL WITH RCX?F/SUSPEf\UED FLOOR SLAB

BEAM

- 81TUMEN FEL T

25 TO 1.0 UNFlLL EDGAP A T TOP

FLOORING/MUDPH USKA WITH TILES

§)R CC SLAB

A. END WALL WITH RooFI B.'SUSPENDED flOOR SLAB

FLOORING/MUD PHUSKAWIT H TILES.

BEDPlAT E

BRICK LAID WIT HVERTICAL J(iINTIN MORT AR

25MM GA"P-FL:AT ASBESTOSCEMENT SHEET ORANY OTHER EQUALLYSUITABlE MATERIAL150MM WIDE

F, EXPANSION JOINT USING·

JOINT FILLER AND SEALINGCOMPOUND

'(Q

©

, 'V" - PLASTER t:~~E" INTERMED!AT E WALL WITH ROOF SLAB MEt:L\L SHEET

HOT BITUMEN PAINTING @17 K·G.f SQM.IN CASEOF ROOF SLAB/ BEAM.- ,HOT 'BITUMEN 'PAlNTING @1·7K·G./ SQM.,8ELOWBRICK WALL ONLY ON SUSPENDED FLOOR,

BEAM{ SLAB.

DRAWING NOr TO SCALE.ALL DIMENSIONS ARE IN M~-1.

EX PAN SIONCHAPTER - R.C.C.C LA USE - 5, 4 . 5FIG. - 24-25.

RAWl PLUG 8, - S;fEWS I '--RAWL PLUG WITH OVALSHAPPEi:; SLOTGAP- L.A. C. SHEET'"

FIG..25 ~J:ISMIC SEPARATION JOINTS DETAIL AT )~Q£f127

.. '•••• 1~' ~

. ' . ~ .. -6----- .. _JI/":r-· //( .. ;'

>~;.-,,.,...., ';,". 1 II L'-'-R .C,c. 5 l A 8MASTIC-·-----'II '41" ••• " ",' ' •• ' ." ,,to _ CEILING Pl.ASTER=r.--t=q .

GAP =t Ji. T ---GA.P

'~_.~ - RAWl PLUG WITH OVALRt.,WL PLUG & SCREW) SHAPPED SLOT

, A.C. SHEET

FI Go24 ~!§.t:1I~ ..._,;~EPARAT ION AT FLOOR LEVEL· ----"R.C.C. COPING , .

• ', :.,..-: ~ •• '4< •• _~ BITUMEN PAINTING .

C.C. GOLA'*...,,;,(/''. ~~.....rBRICK TilES.' .' ••.• / / / '/Y'" ••••• - •• ,y- •••• • ' ••• /7 -L.' .. ' ....

. .- .

<t •••

~... ' .

, .~C]=D::J

1,4 •••. "~.,t':J

"II' , .' • lit'

- -~ '~ ~..",,'"__ I •• -

••• ~ ~ .0#< •.• 11 I

, ;

~_- -SHEET METAL FLASHINf1

BITUMEN

r-- j-RECTANGULAR BARI , - --I ,FLAT. BAR SET IN FORMSI

.••

.. ; -.c ;' •••••• ~' ..

.f-'-...~."r-'-'''', .':..' ,. LR.C.C.SLAB. ' ... ~ . L_CEILING PlA.STER,

• ", ~. t-flLLED UP WITH BITUMENfiLLER,.,.:.,. METAL CR/.•.OLE

••

...

..

....

· .

••

II ..

II>

PRE CAST SL.ABI TILE 5-­

RUBBERISEO PAD-lFLOORING ---,

R.C.C. BEAM-

CON STRUCTION JOINTSCHAPTER - R.C.C.CLAU SE - 5'~' ~FIGURE - 2.&.

- - _(2)-- - - -I!!--::;.ti':~·\>r~.::_·\:~;"...•.... ., : CD. ~.;'ot,-.; ....:: ..•.•. '.; .•.• , •..•"' •.::.;...:,.~:·~.::.;'I.::..)-2 .• ~·a..'L

A .. PROHIBITED JOINT. IN SLAB

(CLAU SE -5'4'4'3)

~~,,:@ "'T<D ' .". ;', .~.:. :.,. :---. '.. .'.~ .

E. JOINT' IN BEAM OR SLAB

, <DJ.l~g4~~=" ="~"-~p{Cl/~rrnING.' . ;JfSASE LEAN aN

F. JOINT IN FLOORING FOR WATER RE.SERVOIRS

B. JOINT 'IN SLAB

(STOP BOARD SLOTTED TOTAKE HORIZONTAL REINFffiCEMENT.)

C, . STOP - BOARD PLAN

H. JOINT IN MONOLITHIC R.C.C,

SLAB AND BEAM CONS T.

'f'E,r';''''';.iliu ---_:_:~1R.C.C. SLAB\!.J "., ••· •.1 • -:- .'~ 7" I ~ ~SECONDARY 8EAM

. ':MAlN BEAM

D. KEY ED JOINTS IN WALLS H. SECTION A - A

(WITH 5 TO P - BOARD FI TrEDWIT H 25 X 25 CHAM FER PIECEAND SLOTTED TO TAKE HORIZONTAL BARS.)

CD RtPRESENTS FIRST. PLACING OF CONCRETE.

<l) REPRESENTS SUBSEQUENT PLACING OF C~CRETE '.

DRAWING NOT TO SCALE.

ALL DIMENSIONS ARE IN. MM.

FIG. -26128

ENCASING ROLLED STEEL SECTIONCHAPTER- R .C.C,CLAUSE-S'S'2FIG, 27 - 28

LAP NOT LESS THAN 100

EXPANDED METALOF UNGAlVANIZEDWIRE MESH

<JV ..-••

• •~••

, . ,-,•,.

..'////0,

· , .~-Y•..

,,, t" ,' .·.' ., .., •., .'.'

.,~ -0-

f-- f-:- "-

"

•.:

, .,"

, •I ,

,, . ."

=~~.r

•.;~

,.. ." -f ' .\'.''10)

, ~

",. ,,"

R.S. JOIST

.•--

),,: \--+-{EXPANDED METAL ORR.S, JOIST: ,. ',' UNGALVANIZED WIRE MESH

. .

..•

..

,. .• t?777//~ ~

.. .•

•- "

RC,C,SLAB

FIG. 27

; , ., •

STEEL COLUMN

5 DfA WIRE HANGER AT 1200 C/c

"'-," . ~ ,., .•

.•.-' ... "

..

~5j,251.

"FIG. 2 8 STEEL BEAM WITH SLAB, .

NORMALLY CEMENT CONCRETE 1:2:1. (1 CEMENT:2 COARSE SAND: 4 GRADED S TONE AGGREGATE12,5 NOMINAL S,IZE) SHALL BE USED.

DRAWING NOT TO SCALEALL i DIMENSIONS ARE IN MM

129

MILD

R. C.Co· DOOR .& WINDOW' FRAMESCHAPTER· R.C,C.CLAUSE·5·9·2 «.

5,9,3,4FIGURE - 29.

~CEMENT MORTAR;:2 .

CAOLKED ~(.1CEMENT:. 2 COARSE SAND)

HORN DETAIL

AT X

~Il'-iii,1:1 .

~t.n

OPT laNAI. ONl Y­IN 'AS £ OF~k PIE .

FRAME

HINGEFORSTOPPER

HINGEFORSHUTTER

BOLT

NOTE: Insteod of bolts for hdd fas tm.s. rod 10 mm ~ may be .embedded in concrete &. the

.,projec1ed pieces 'may, bebent after casting. '"

-MILD STEtL ANGLE IRON ORA NY OTHER EQUALLY SUITABLE

ARRAN GErvlEN T

All dimensions 01 mm.

I..()

---~ L10rnmfi bolt

".:.'~.v~r j.a.sh"do fast.

=-- 2 nos. m.s.· 0 .... "i ..

'I! ., XS··· N.,~ats:30'· mm ..•; I Co, ,size It '70 In'' ,___ .'V_ rarn. Q 19- _

'~120 f ~bNGE. tR = 30,35 OR40 MM DEPEN DING UPON

THE. THICKNESS OF SHUTTER

E!..!L ·',29 ( C )ALTER NA TlVE D ET AI LS OF PR E·CAS T REINFORCED CONCRETE DOOR ~

R = 30, 35 OR L.OMM DEPENDiNG UPON . WINDOW /FRAME .SHOWING ARRANGEMENTTHE THICKNESS OF SHLJTTER j fOR· REINFORCEMENT , HOlDFASTS & HINGES.

FIG.- 29(b) CROSS SECTION OF PRECAST -REINFORCED CONCRETE DOOR AND 'WINDOW' FRAME SHOWING REINFORCEMENT

GROOVE FOR J. WA L L PlAS TER

". ._PRECAS T RE INFORCED' CONCRETE3 mm d> m.s. wi reties@>300 mm clc

25

oN

CONCRETE DOOR AND WINDOW . F~AME

,130

DOOR & WINDOW FRAMES

Wall fate

~60 "/1 /l

CHAPTER - R. C.e:CLAUSE - 5·9·2

I·h· ~ t FiGURE;.. 30 .- Ice 5S 0sui t the sizeof rebate(See

R in fig1~)

b mm 11

boll

GroutedJ \-Nut

FIc;3cmHINGE FIXED DIREqLY ON R.C.c. FRAME

FIG .30{el~_6IL~HINGE FIXED ON TIMBER FRAfv'£ HINGE FIXED(DOUBLE SHUTTER R.e.c. FRAME) DRECTLY ON

FIG. 30(c) R.C.e. FRAMEARRANGEMENTS FOR FIXING HINGES TO PRFCAST ARRANGEMENTS FOR FIXING HINGES TO

REINFORCED C(]\ICRETE DOOR 8. WINDOW FRAMES . PRECAS T R.C. DOOR 8. WIf'UOW FRAMES

6mm 4Jbars ~3 mm $ stirrups' 75

:~+~--~---~---:-~;-----;--1 H~"I.• r~,.--=t20 ~- -__-__ ~ ,- - . u_ 2~ -:: , _J. -1-- ,

30 I Hole to : I I

- L 80 receive tow~r I 1 :

1-'-1 + bol t I I ,11 110 _ : I :T- I I I~6mm $ bars I

~60 r

6mm $ ... ~!b oM ---. .•.. ::,:, v

'-.... .~ ...-......•• #

R.c.e. Fram-~· .:..:

Hing e--'

FIG. 30th) HINGE FIXED ON

TIMBER FRAM~

+~Q

o

25'-20::-5

6mm thick m.5 .pllateGmm¢1bars'

FIG. 30{g) ~ETHOD OF flXlNG ,TOWER BOLTSTO R.C.C. FRAMES

AI! dimensions in mm.

13f

NOTES

132

/NOTES

133