Report Gadchiroli

8/4/2019 Report Gadchiroli

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CONTENT General Scope of work Layout Earthwork

P.C.C. Reinforecement Reinforced cement concrete work Shuttering work/ deshuttering work Brick work Water proofing Finishing Flooring Joint- construction joint and expanssion joint Sheets


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1. GENERAL

Name of work: Construction of Administrative Building,Hostel Building & Mess Building includingInfrastructural amenities with Roads &

Electrification for Agriculture College on landof S.No 128,129 at Mouza SonapurGadchiroli, Tah-Dist- Gadchiroli for Dr.Panjabrao Deshmukh Krishi Vidyapeeth Akola

Location of Site: Opposite K.K.V Building, Mouza- SonapurChandrapur Rd, Gadchiroli.

Contractor:

Engineer-in-Charge:

Site Engineer:

Cost of the Project: Rs 24,78,00,000 /-

Duration of the Project:

Grade of Concrete Used: For PCC: M10, M15For Construction: M20

Grade of Steel Used: Fe415

Diameter of Bars Used: 8,12,16,20 mm

Building: G+2 (R.C.C framed structure)

IS: The standards, specification and code of practices issued by the Bureau of IndianStandards.

Department:Department shall mean Central Public Works Department (CPWD).


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General Scope of work

Administrative Building

a. Ground floor Area 4059.341 sq.mHaving following facilities1. Lab 10 No.2. Museum/Lab- 2 No.3. Store room 08 No.4. Dept. H.O.D Rooms 04 No.5. Staff room 056. Waiting Area7. Electric Panel Room 1 No.

8. Seminar Hall9. Conference Hall10. Office Space11. Principal cabin12. Records Room13. Sitting Hall14. Lobby15. Pantry 02 No.16. Toilet Blocks - 06 No.17. Porch

b. First Floor (Area 3695.90 Sq.m)Having following facilities1. Lab 5 No.2. Museum 1 No.3. Store room - 8 No.4. Class Room - 3 No.5. Staff Room 02 No.6. Dep H.O.D Rooms 02 No.7. Electric Panel Room 1 No.

8. Reading Room9. General Reading Room10. Librarian Room11. Book Issue Counter12. Computer Room13. Server Room14. Digestion Chamber15. Disilation Room16. Gents Common Room17. Ladies Common Room18. Lobby

19. Pantry 2 No.20. Toilet Blocks 6 No.


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c. Second Floor (Area 3682.667 Sq.m)Having following facilities

1. Lab 5 No.2. Museum 1 No.3. Store room - 8 No.4. Staff Rooms - 4 No.5. Utility Room 1 No.6. Electric Panel Room 1 No.7. Dept H.O.D Rooms 04 No.8. Examination Hall 02 No.9. Work Experience Room10. Isolation Chamber11. Media Room

12. Lobby13. Pantry 2 No.14. Toilet Blocks 6 No.

Boys Hostel

a. Ground Floor (Area 659.985 Sq.m.)Having following facilities

1. Rooms 13 No.2. Rector Room 1 No.3. Drying Area 2 No.4. Utility Room 1 No.5. Entrance Foyer6. Toilet Blocks 2 No.7. Attached Toilet 1 No.8. Toilet Block for Mess

b. First Floor (Area 659.985 Sq.m.)

Having following facilities

1. Rooms 14 No.2. Drying Room 2 No.3. Reading Room -1 No.4. Lobby5. Toilet Block 2 No.


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c. Second Floor (636.102 Sq.m.)Having following facilities

1. Rooms 142. Drying Area 2 No.3. Recreation Room 1 No.4. Lobby5. Toilet Block 2 No.

Mess Building

a. Ground Floor (Area 517.994 Sq.m)

Having following facilities1. Dinning Hall2. Hand Wash Room3. Water Cooler Room4. Vegetable Cooking Area5. Preparation Area6. Pantry Room7. Store Room + LPG Store8. Chapatti Room9. Mess Incharge Room

Girls Hostela. Ground Floor (Area 823.997 Sq.m)Having following facilities

1. Rooms 13 No.2. Rector Room 1 No.3. Drying Area 2 No.4. Entrance Foyer5. Dinning Hall6. Hand Wash Room7. Water Cooler Room

8. Vegetable Cooking Area9. Preparation Area Room10. Pantry Room11. LPG Store Room12. Chapatti Room13. Mess Incharge Room14. Store Room15. Toilet Block 2 No.16. Toilet Block for Mess17. Attached Room

b. First Floor (Area 659.985 Sq.m)Having following facilities


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1. Room 14 No.2. Drying Area 2 No.3. Reading Room4. Lobby5. Toilet Block 2 No.

c. Second Floor (Area 636.102 Sq.m)Having following facilities

1. Rooms 14 No.2. Drying Area 2 No.3. Recreation Room4. Lobby5. Toilet Block 2 No.

Infrastructure1. Area development ,cutting ,filling, leveling Area development with cutting /

filling / leveling site w.r.t. average ground / contour level and as directed byengineer in charge.

2. Road Works WBM roads is constructed, including excavation, disposing offthe excavated soil, supplying material.

3. Storm water drain RCC Strom water drain with precast RCC cover inspecified areas.

4. Under Ground storage water tank RCC structure with capacity of approx.100000 Ltrs.

5. ESR Constructing RCC elevated service reservoir with RCC staging.Capacity of ESR 100000 Ltrs.

6. Septic tanks - Septic tanks and soak pits of specified sizes.7. Compound wall 0.23 mtr thick compound wall in fly ash bricks with RCC

footing, columns and beams as per design specified.8. External electrification Street light poles along the roads, transformer (500

KVA) with H.T Cubical room & solar lights are provided.9. Open well - Open well (one no.) of 6 mtr inner diameter with RCC side wall to

a depth of 15 mtr minimum is constructed in premises.10. Bore well - Bore well of 150 mm dia (two nos) each to a depth of 150 mtr

minimum or more.11. Chicken mesh chicken mesh is provided at all joints of Fly Ash BrickMasonry RCC internally and externally for all the building.

2. LAYOUT

General Definitions

Layout of Building


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The real meaning and purpose of setting out (layout) is to transfer the plan, lengthand width of its foundation on the ground so that the foundation can be excavated forconstruction of purposed building as per drawing.

Base Line

For setting out /layout, the most important requirement is to establish a baseline.This is marked on the ground as per site plan requirement with the help of offsetswhich are taken from the existing road or existing building.

Centre Line

Centre line divides the plan into two equal parts. This can be marked in the field withthe help of baseline. This line is very necessary and useful for layout. This lineshould be transferred to Burjis and be kept up to the completion of foundation work.

.

Procedure for Setting Out and Marking of Building Layout on the SiteA. List of materials required for setting out work

1. Leveling instrument2. 100 mm diameter Balli pieces 500 to 600 mm long (depending upon

site conditions)3. 35 mm long nails4. Right angle (GUNIYA) Masons as well as that of carpenter5. Hammer6. Steel tape : 30 m long7. Steel tape : 15 m long8. Steel tape : 3 m long9. Pencil or ball pen10. Thin cotton thread ( line dori )11. Bricks12. Cement13. Screened sand14. Lime powder15. Theodolite (only for major structures)

B. Preliminary works1. The site should be cleared of all the grass, bushes, trees, etc.2. Spot levels of ground should be recorded.3. A permanent bench mark is to be constructed in the vicinity, in case the

plinth of any permanent building which can be treated as bench mark isnot available nearby.

C. Drawings required for layout1. Key plan2. Ground floor plan

3. Footing and column drawings


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General DefinitionsDeadmen or Tell Tales: Moulds of earth left undisturbed in pits dug out forborrowing earth.

Burjis: Short pillars of brick/stone having top surface finished with cement plaster for

marking etc.

Formation or Profile: Final shape of the ground after excavation or feeling up.

Lead: All distances shall be measured over the shortest practical route and shortestpractical route and not necessary the route actually taken. Route other than shortestpractical route may be considered in case of unavoidable circumstances.Carriage by manual labour shall be reckoned in units of 50 meters or part thereof.Carriage by animal and mechanical transport shall be reckoned in one km.

Lift: The vertical distance for removal with reference to the ground level. The

excavation up to 1.5 meters depth below the ground level and depositing theexcavated materials upto 1.5 meters.Type of SoilAll Kinds of SoilsGenerally any strata, such as sand, gravel, loam, clay, mud, black cotton moorum,shingle, river or nallah bed boulders, siding of roads, paths etc. and hard core,macadam surface of any description (water bound, grouted tarmac etc.), limeconcrete mud concrete and their mixtures which for excavation yields to applicationof picks, showels, jumper, sacrifiers, ripper and other manual digging implements.

Excavation in All Kinds of SoilsAll excavation operations manually or by mechanical means shall include

excavation and getting out the excavated materials. In case of excavation fortrenches, basements, water tanks etc. getting out shall include throwing theexcavated materials at a distance of at least one metre or half the depth ofexcavation, whichever is more, clear off the edge of excavation. In all other casesgetting out shall include depositing the excavated materials as specified. Thesubsequent disposal of the excavated material shall be either stated as a separateitem or included with the items of excavation stating lead. During the excavation thenatural drainage of the area shall be maintained. Excavation shall be done from topto bottom. Undermining or undercutting shall not be done.

In firm soils, the sides of the trenches shall be kept vertical upto a depth of 2 metresfrom the bottom. For greater depths, the excavation profiles shall be widened byallowing steps of 50 cms on either side after every 2 metres from the bottom.Alternatively, the excavation can be done so as to give slope of 1:4 (1 horizontal : 4vertical). Where the soil is soft, loose or slushy, the width of steps shall be suitablyincreased or sides sloped or the soil shoredThe excavation shall be done true to levels, slope, shape and pattern. Only theexcavation shown on the drawings with additional allowances for centering andshuttering.In case of excavation for foundation in trenches or over areas, the bed of excavationshall be to the correct level or slope and consolidated by watering and ramming. If

the excavation for foundation is done to a depth greater than that shown in the


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drawings. Soft/defective spots at the bed of the foundations shall be dug out andfilled with concrete.While carrying out the excavation for drain work care shall be taken to cut the sideand bottom to the required shape, slope and gradient. The surface shall then beproperly dressed. If the excavation is done to a depth greater than that shown on the

drawing, the excess depth shall be made good with stiff clay puddle at places wherethe drains are required to be pitched and with ordinary earth, properly watered andrammed, where the drains are not required to be pitched. In case the drain isrequired is to be pitched, the back filling with clay puddle, if required, shall be donesimultaneously as the pitching work proceeds. The brick pitched storm water drainsshould be avoided as far as possible in filled-up areas and loose soils.In all other cases where the excavation is taken deeper, it shall be brought to therequired level by filling in with earth duly watered, consolidated and rammed.The excavation shall be done manually or by mechanical means consideringfeasibility, urgency of work, availability of labour /mechanical equipments and otherfactors involved.

Site ClearanceBefore earth work is started, the area coming under cutting and filling shall becleared of shrubs, rank vegetation, grass, brushwood, trees and saplings of girth upto 30cm measured at a height of one meter above ground level and rubbish removedup to a distance of 50 meters outside the periphery of the area under clearance. Theroots of these and saplings shall be removed to a depth of 60 cm below ground levelor 30 cm below formation level or 15 cm below sub grade level, whichever is lower,and the holes or hollows filled up with the earth, rammed and leveled.The trees of girth above 30 cm measured at a height of one metre above groundshall be cut and the roots of the trees shall also be removed.Existing structures and services such as old buildings, culverts, fencing, and watersupply pipe lines, sewers. Power cables, communication cables, drainage pipes etc.within or adjacent to the area if required to be diverted/removed, shall bediverted/dismantled.In case of archeological monuments within or adjacent to the area, the necessaryfencing all around such monuments shall be provided and protect same propertyduring execution of works.Lead of 50 m as mentioned is the average lead for the disposal of excavated earth

within the site of work. The actual lead for the disposal of earth may be more or lessthan the 50 m.Disposal of earth shall be disposed off at the specified location

Protections1. Excavation shall be securely barricaded and provided with proper caution signs,conspicuously displayed during the day and properly illuminated with red lightsand/or written using fluorescent paint during the night to avoid accident.2. The excavator shall take adequate protective measures to see that the excavationoperations do not damage the adjoining structures or dislocate the services. Watersupply pipes, sluice valve chambers, sewerage pipes, manholes, drainage pipes and

chambers, communication cables, power supply cables etc. met within the course ofexcavation shall be properly supported and adequately protected, so that these


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services remain functional. However, if any service is damaged during excavationshall be restored in reasonable time.3. Excavation shall not be carried out below the foundation level of the adjacentbuildings until underpiping, shoring etc. is done.

Procedure for Excavation for Footing1. For excavation plot the dimensions of footing should be exceeded on all sides by600mm from face of the footing using the centre lines and centre points marked onthe site.2. Take RL of centre of columns or divide the site into parts by drawing the horizontaland vertical grids like lines naming them as A,B,C etc horizontally and 1,2,3 etcvertically.3. The depth of excavation is upto 1.80m such that hard rock/strata should bereached.4. Use bulldozer for excavation and the excavated material is dumped into the truckwhich will dump it to the desired location.

Photos


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4. PCC

4.1 GeneralPCC means plain cement concrete. It provides firm base for footing and avoidsdirect contact between soil and concrete.Normally M10 grade concrete is being used for the PCC.

4.2 Procedure for PCC for Footings

1. After completion of excavation for footings, project the centre lines and centrepoints on the excavated surface.2. Mark the dimensions of PCC for footings such that offset/projection of 150mmfrom the dimensions of footings should be available from all sides.The depth is 100mm.3. PCC work is to be done for plinth beams.4. M-5 grade PCC is used for plinth beams Plinth Beams5. Normally PCC is used only for outer beams.6. Depth is normally 75mm.

Photos


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5. SHUTTERING WORK / DESHUTTERING WORK

FORM WORK

Form WorkForm work shall include all temporary or permanent forms or moulds required forforming the concrete which is cast-in-situ, together with all temporary constructionrequired for their support.

Material for ShutteringSteel plates, wooden plates, steel rods or bamboos, wooden plate cutter, nails,hammer, steel plate supporters.

Erection of Form Work (Centering and Shuttering)Following Points Shall be Taken Into Consideration(a) Any member which is to remain in position after the general dismantling is done

should be clearly marked.(b) Material used should be checked to ensure that, wrong items/ rejects are not

used.(c) If there are any excavations nearby which may influence the safety of form works,

corrective and strengthening action must be taken.(d) (i) The bearing soil must be sound and well prepared and the sole plates shall

bear well on the ground.(ii) Sole plates shall be properly seated on their bearing pads or sleepers.(iii) The bearing plates of steel props shall not be distorted.(iv) The steel parts on the bearing members shall have adequate bearing areas.

(e) Safety measures to prevent impact of traffic, scour due to water etc. should betaken. Adequate precautionary measures shall be taken to prevent accidentalimpacts etc.

(f) Bracing, struts and ties shall be installed along with the progress of form work toensure strength and stability of form work at intermediate stage. Steel sections(especially deep sections) shall be adequately restrained against tilting, over

turning and form work should be restrained against horizontal loads. All thesecuring devices and bracing shall be tightened.(g) The stacked materials shall be placed as catered for, in the design.(h) When adjustable steel props are used.

They should -1. be undamaged and not visibly bent.2. have the steel pins provided by the manufacturers for use.3. be restrained laterally near each end.4. have means for centralizing beams placed in the forkheadss.

(i) Screw adjustment of adjustable props shall not be over extended.(j) Double wedges shall be provided for adjustment of the form to the required

position wherever any settlement/ elastic shorting of props occurs. Wedgesshould be used only at the bottom end of single prop. Wedges should not be too


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steep and one of the pair should be tightened/ clamped down after adjustment toprevent shifting.

(k) No member shall be eccentric upon vertical member.(l) The number of nuts and bolts shall be adequate.(m) All provisions of the design and/or drawings shall be complied with.

(n) Cantilever supports shall be adequate.(o) Props shall be directly under one another in multistage constructions as far as

possible.(p) Guy ropes or stays shall be tensioned properly.(q) There shall be adequate provision for the movements and operation of vibrators

and other construction plant and equipment.(r) Required camber shall be provided over long spans.(s) Supports shall be adequate, and in plumb within the specified tolerances.

ShutteringShuttering used shall be of sufficient stiffness to avoid excessive deflection and jointsshall be tightly butted to avoid leakage of slurry. If required, rubberized lining ofmaterial shall be provided in the joints. Steel or wooden shuttering used or concretingshould be sufficiently stiffened. The steel shuttering should also be properly repairedbefore use and properly cleaned to avoid stains, honey combing, seepage of slurrythrough joints etc.

Surface TreatmentOiling the SurfaceShuttering gives much longer service life if the surfaces are coated with suitablemould oil which acts both as a parting agent and also gives surface protections.A typical mould oil is heavy mineral oil or purified cylinder oil containing not less than5% pentachlorophenol well mixed to a viscosity of 70-80 centipoises.After 3-4 uses and also in cases when shuttering has been stored for a long time, itshould be recoated with mould oil before the next use.The second categories of shuttering oils / leavening agents are Polymer basedwater soluble Compounds. They are available as concentrates and when useddiluted with water in the ratio of 1:20 or as per manufacturer specifications. Thediluted solution is applied by brush applications on the shuttering both of steel as wellas ply wood. The solution is applied after every use.

Inspection of Form WorkThe completed form work shall be inspected and approved before the reinforcementbars are placed in position.Proper form work should be adopted for concreting so as to avoid honey combing,blow holes, grout loss, stains or discoloration of concrete etc. Proper and accuratealignment and profile of finished concrete surface will be ensured by properdesigning and erection of form work.Shuttering surface before concreting should be free from any defect/ deposits and fullcleaned so as to give perfectly straight smooth concrete surface. Shuttering surfaceshould be therefore checked for any damage to its surface and excessive roughness

before use.


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Procedure1. Shuttering provides support to the concrete in its liquid state. When concrete getshardened, shuttering work is to be removed. ISI marked wooden ply is used forshuttering for footing, column, beam, etc. Steel plates are being used for shutteringwork of slab.

2. For shuttering, we have to make the boxes of the size of footing or column orbeam etc. and we have to fix it in such that during concreting it should not getsdisturbed. For that we have to provide support from all sides.3. On inner surface of the shuttering we have to apply oil so that shuttering wood andconcrete should not get sticked and deshuttering work should be easy.4. Nail is to be hammered to indicate the level of concreting.

Photos.

6. REINFORCEMENTS

6.1 Steel for ReinforcementThe steel used for reinforcement shall be any of the following types:(a) Mild steel and medium tensile bars(b) High strength deformed steel bars(c) Hard drawn steel wire fabric(d) Structural steel(e) Thermo-mechanically treated (TMT) Bars.Elongation percent on gauge length is 5.65 A where A is the cross sectional areas ofthe test piece.Mild steel is not recommended for the use in structures located in earthquake zonesubjected to severe damage.

6.2 General RequirementsSteel conforming for reinforcement shall be clear and free from loose mill scales,dust, loose rust, coats of paints, oil or other coating which may destroy or reducebond. It shall be stored in such a way as to avoid distortion and to preventdeterioration and corrosion. Prior to assembly of reinforcement on no account anyoily substance shall be used for removing the rust.

Bars shall be bent correctly and accurately to the size and shape as shown in thedetailed drawing. Preferably bars of full length shall be used. Necessary cutting andstraightening is also included. Overlapping of bars, where necessary shall be done.The overlapping bars shall be bound together at intervals not exceeding twice thedia. of such bars with two strands annealed steel wire of 0.90 mm to 1.6 mm twistedtight. But in no case the overlapping shall be provided in more than 50% of crosssectional area at one section.

The Structural Requirements of Reinforcing Steel: Tensile strength


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Weldability Bond strength Fatigue strength Ductility Corrosion resistance

Bendability Fire resistance

6.4 Bonds and Hooks Forming End AnchorageReinforcement shall be bent and fixed in accordance with procedure specified in IS2502, code of practice of bending and fixing of bars for concrete reinforcement.

Anchoring Bars in TensionDeformed bars may be used without end anchorages provided, development lengthequipment is satisfied. Hooks should normally be provided for plain bars in tension.

Anchoring Bars in CompressionThe anchorage length of straight bar in compression shall be equal to theDevelopment length of bars in compression. The projected length of hooks, bendand straight lengths beyond bend, if provided for a bar in compression, shall beconsidered for development length.

Binders, stirrups, links etc.In case of binders, stirrups, links etc. the straight portion beyond the curve at the endshall be not less than eight times and nominal size of bar.

Placing in PositionFabricated reinforcement bars shall be placed in position. The bars crossing oneanother shall be tied together at every intersection with two strands of annealed steelwire 0.9 to 1.6 mm thickness twisted tight to make the skeleton of the steel work rigidso that the reinforcement does not get displaced during deposition of concrete.

The bars shall be kept in correct position by the following methods(a) In case of beam and slab construction pre-cast cover blocks in cement mortar 1:2

(1 cement : 2 coarse sand) about 4x4 cm section and of thickness equal to thespecified cover shall be placed between the bars and shuttering, so as to secure andmaintain the requisite cover of concrete over reinforcements.(b) In case of cantilevered and doubly reinforced beams of slabs, the verticaldistance between the horizontal bars shall be maintained by introducing chairs,spacers or support bars of steel at 1.0 mere or at shorter spacing to avoid sagging.(c) In case of columns and walls, the vertical bars shall be kept in position by meansof timber templates with slots accurately cut in them: or with clock of cement mortar1:2 (1 cement: 2 coarse sand) of required size suitable tied to the reinforcement toensure that they are in correct position during concreting.


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MeasurementReinforcement including authorized spacer bars and lappages shall be measured inlength of different diametre, as actually (not more than as specified in the drgs.) usedin the work nearest to a centimetre and their weight calculated on the basis ofstandard weight. In case of the bars is less than standard unit weight, but withinvariation, in such cases weight of reinforcement shall be calculated on the basis ofactual unit weight.

TABLE


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Cross Sections Area and Mass of Steel BarNominal Size mm Cross sectional Area

Sq.mmMass per metre Run Kg

6 28.3 0.2228 50.3 0.395

10 78.6 0.61712 113.1 0.88816 201.2 1.5820 314.3 2.4725 491.1 3.8528 615.8 4.8332 804.6 6.3136 1018.3 7.9940 1257.2 9.86

ProcedurePrepare the steel grill for footings as per approved drawing and lay it on PCC surfaceand provide cover 60mm from all sides.Provide Columns reinforcement on the footings reinforcement with developmentlength should be 16xDia.of bar here 300mm.Reinforcement for plinth beams should be provided with development length toadjacent columns.Reinforcement for slab and beam should be provided in combination.

. CEMENT CONCRETE WORK

7.1 General

MaterialWater, cement, fine aggregate or sand, surkhi, and fly ash.

Coarse AggregateAggregate most of which is retained on 4.75 mm IS Sieve and contains only asmuch fine material as is permitted for various sizes and grading is known as coarseaggregate.Coarse aggregate shall be specified as stone aggregate, gravel or brick aggregateand it shall be obtained from approved/ authorized sources.

Stone AggregateIt shall consist of naturally occurring (uncrushed, crushed or broken) stones. It shall

be hard, strong, dense, durable and clean. It shall be free from veins, adherent


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coating, injurious amounts of disintegrated pieces, alkali, vegetable matter and otherdeleterious substances. It shall be roughly cubical in shape. Flaky and elongatedpieces shall be avoided.

Deleterious Material

Coarse aggregate shall not contain any deleterious material, such as pyrites, coal,lignite, mica, shale or similar laminated material, clay, alkali, soft fragments, seashells and organic impurities in such quantity as to affect the strength or durability ofthe concrete. Coarse aggregate to be used for reinforced cement concrete. Coarseaggregate to be used for reinforced cement concrete shall not contain any materialliable to attack the steel reinforcement. Aggregates which are chemically reactivewith alkalies of cement shall not be used. The maximum quantity of deleteriousmaterial shall not be more than five percent of the weight of coarse.

Size and Grading(a) Nominal sizes of graded stone aggregate or gravel shall be 40, 20, 16, or 12.5

mm as specified.(b) Nominal sizes of single sized stone aggregate or gravel shall be 63, 40, 20, 16,12.5 or 10 mm as specified.(c) When stone aggregate or gravel brought to site is single sized (ungraded), it shallbe mixed with single sized aggregate of different sizes in the proportion to bedetermined by field tests to obtain graded aggregate of specified nominal size.

7.2 BatchingTo avoid confusion and error in batching, consideration should be given to using thesmallest practical number of different concrete mixed on any site or in any one plant.In batching concrete, the quantity of both cement and aggregate shall be determinedby mass; admixture, if solid, by mass: liquid admixture may however be measured involume or mass: water shall be weighed or measured by volume in a calibrated tank.

7.3 Ready Mixed ConcreteReady-mixed concrete supplied by ready-mixed concrete plant shall be preferred.For large and medium project sites the concrete shall be sourced from ready-mixedconcrete plants or from on site or off site batching and mixing plants.Except where it can be shown to the satisfaction that supply of properly gradedaggregate of uniform quality can be maintained over a period of work, the gradingaggregate should be controlled by obtaining the coarse aggregate in different sizes

and blending them in the right proportions when required, the different sizes beingstocked in separate stock-piles. The material should be stock-piled for several hourspreferably a day before use. The grading of coarse and fine aggregate should bechecked as frequently as possible, the frequency for a given job being determined toensure that the specified grading is maintained.Proportion/Type and grading of aggregates shall be made by trial in such a way soas to obtain densest possible concrete. All ingredients of the concrete should beused by mass only.

7.4 Chemical AdmixturesWhen required, admixtures of approved quality shall be mixed with concrete, as

specified.Admixtures may be any one of the following classes for use in concrete


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(a) Water Reducing Admixtures(b) Retarding Admixtures(c) Accelerating Admixtures(d) Water Reducing and Retarding Admixtures(e) Water Reducing and Accelerating Admixtures

(f) Permeability Reducing (water proofing) Admixtures

Liquid AdmixturesAdmixtures introduced into the concrete as liquids generally fall into thefollowing categories(a) Air Entraining.(b) Water Reducing.(c) Water Reducing Retarders.(d) Retarders.(e) Water Reducing Accelerators.(f) Accelerators.

Dosage of these admixtures may vary according to manufacturers specification.Two or more admixtures may not be compatible in the same solution. It is thereforemandatory that when two admixtures manufactured by the same manufacturers isbeing used simultaneously, the manufacturer shall certify their compatibility. In casethe two or more admixtures are produces by different manufacturers, then, beforetheir use in concrete, test shall be performed by the manufacturer to establish theircompatibility.Some admixture may be in the form of powder, particle or high concentration liquidswhich may require mixing with water prior to dosing. Under these conditions water insolution shall be considered as part of total water content in the batch in order tomaintain the water-cement ratio.Certain admixtures may contain significant amounts of finely divided insolublematerials or active ingredients which may or may not be readily soluble. It is essentialfor such admixtures that precautions be taken to ensure that these constituents bekept in a state of uniform suspension before actual batching. When relatively smallamounts of powered admixtures are to be used directly, these shall be pre-blendedwith cement.The proprietary name and the net quantity of content shall be clearly indicated ineach package or container of admixtures. The admixtures shall be uniform withineach batch and uniform between all batches.

7.5 MixingConcrete shall be mixed in mechanical batch type concrete mixers having twoblades and fitted with power loader (lifting hopper type). Half bag mixers and mixerswithout lifting hoppers shall not be used for mixing concrete.When hand mixing is permitted, it shall be carried out on a water tight platform andcare shall be taken to ensure that mixing is continued until the concrete is uniform incolour and consistency. Before mixing the stone aggregate or gravel shall be washedwith water to remove, dirt, dust and other foreign materials. For guidance, the mixingtime may be 11/2 to 2 minutes, for hydrophobic cement it may be taken as 21/2 to 3minutes.

Mixing Efficiency


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The mixer shall be tested under normal working conditions with a view to check itsability to mix the ingredients to obtain concrete having uniformity within theprescribed limits. The uniformity of mixed concrete shall be evaluated by finding thepercentage variation in quantity (mass in water) of cement, fine aggregate andcoarse aggregate in a freshly mixed batch of concrete.

The percentage variation between the quantities of cement, fine aggregate andcoarse aggregates (as found by weighing in water) in the two halves of a batch andaverage of the two halve of the batch shall not be more than the following limits

Cement 8%Fine aggregate 6%

Coarse aggregate 5%

Machine MixingThe mixer drum shall be flushed clean with water. Measured quantity of coarseaggregate shall be placed first in the hopper. This shall be followed with measuredquantity of fine aggregate and then cement. In case fine aggregate is damp, half therequired quantity of coarse aggregate shall be placed in the hopper, followed by fineaggregate and cement. Finally the balance quantity of coarse aggregate shall be fedin the hopper, & then the dry materials are slipped into the drum by raising thehopper. The dry material shall be mixed for atleast four turns of the drum. While thedrum is rotating, water shall be added gradually to achieve the water cement ratio asspecified or as required. After adding water, the mixing shall be continued untilconcrete of uniform colour, uniformly distributed material and consistency isobtained. Mixing shall be done for atleast two minutes after adding water. If there issegregation after unloading from the mixer, the concrete should be remixed.The drum shall be emptied before recharging. When the mixer is closed down for

the day or at any time exceeding 20 minutes, the drum shall be flushed cleaned withwater.

Hand MixingWhen hand mixing has been specifically permitted in exceptional circumstances,subject to adding 10% extra cement, it shall be carried out on a smooth, clean andwater tight platform of suitable size. Measured quantity of sand shall be spreadevenly on the platform and the cement shall be dumped on the sand and distributedevenly. Sand and cement shall be mixed intimately with spade until mixture is ofeven colour throughout. Measured quantity of coarse aggregate shall be spread ontop of cement sand mixture and mixing done by showlling and turning till the coarse

aggregate gets evenly distributed the cement sand mixture. Three quarters of thetotal quantity of water required shall be added in a hollow made in the middle of themixed pile and the material is turned towards the middle of pile with spade. Thewhole mixture is turned slowly over and again and the remaining quantity of water isadded gradually. The mixing shall be continued until concrete of uniform colour andconsistency is obtained. The mixing platform shall be washed and cleaned at the endof the day.

7.6 Transportation and HandlingConcrete shall be transported from the mixer to the place of laying as rapidly aspossible by methods which will prevent the segregation or loss of any of the

ingredients and maintaining the required workability.


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During hot or cold weather, concrete shall be transported in deep containers, othersuitable methods to reduce the loss of water by evaporation in hot weather and heatloss in cold weather may also be adopted.

7.7 Placing

The concrete shall be deposited as nearly as practicable in its final position to avoidrehandling. It shall be laid gently (not thrown) and shall be thoroughly vibrated andcompacted before setting commences and should not be subsequently disturbed.Method of placing shall be such as to preclude segregation. Care shall be taken toavoid displacement of reinforcement or movement of form work and damage due torains. As a general guidance, the maximum free fall of concrete may be taken as 1.5metre.

7.8 CompactionConcrete shall be thoroughly compacted and fully worked around embedded fixturesand into corners of the form work. Compaction shall be done by mechanical vibrator

of appropriate type till a dense concrete is obtained. To prevent segregation, overvibration shall be avoided.Compaction shall be completed before the initial setting starts. After compaction thetop surface shall be finished even and smooth with wooden trowel before theconcrete begins to set.

7.9 CuringCuring is the process of preventing loss of moisture from the concrete. The followingmethods shall be employed for effecting curing.Moist CuringExposed surfaces of concrete shall be kept continuously in a damp or wet conditionby ponding or by covering with a layer of sacking, canvas, Hessian or similarmaterials and kept constantly wet for at least 7 days from the date of placingconcrete in case of Ordinary Portland Cement and at least 10 days where mineraladmixtures or blended cements are used. The period of curing shall not be less than10 days for concrete exposed to dry and hot weather conditions. In the case ofconcrete where mineral admixtures or blended cements are used, it is recommendedthat above minimum periods may be extended to 14 days.

Membrane CuringApproved curing compounds may be used in lieu of moist curing. Such compound

shall be applied to all exposed surfaces of the concrete as soon as possible after theconcrete has set. Impermeable membrane such as polythene sheet covering theconcrete surface may also be used to provide effective barrier against theevaporation.Freshly laid concrete shall be protected from rain by suitable covering.Over the foundation concrete, the masonry work may be started after 48 hours of itscompaction but the curing of exposed surfaces of cement concrete shall becontinued along with the masonry work for at least 7 days. And where cementconcrete is used as base concrete for flooring, the flooring may be commencedbefore the curing period of base concrete is over but the curing of base concreteshall be continued along with top layer of flooring for a minimum period of 7 days.

7.10 Durability of Concrete


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A durable concrete is one that performs satisfactorily in the working environmentduring its anticipated exposure conditions during service. The materials and mixproportions shall be such as to maintain its intergrity and, if applicable, to protectreinforcement from corrosion.The factors influencing durability include

(a) The environment(b) The cover to embedded steel(c) The type and quality of constituent materials(d) The cement content and water/ cement ratio of the concrete(e) Workmanship, to obtain full compaction and efficient curing and(f) The shape and size of the member.

11 Grades of Cement ConcreteThe concrete shall be in grade designated asTABLE

Group Grade Designation Specified characteristiccompressive strength of

150 mm Cube at 28 Daysin N/mm2

(1) (2) (3)Ordinary Concrete M10

M15M20

10

1520


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Standard Concrete M25M30M35M40M45

M50M55

2530354045

5055

High Strength Concrete M60M65M70M75M80

6065707580

Notes1. In the designation of concrete mix M refers to the mix and the number to the

specified compressive strength of 150 mm size cube at 28 days, expressed inN/mm2.2. The minimum grade of concrete for plain and reinforced concrete shall be as perTable.

7.12 Workability of ConcreteThe concrete mix proportion chosen should be such that the concrete is of adequateworkability for the placing conditions of the concrete and can properly be compactedwith the means available

8. BRICK WORK

8.1 TerminologyBondThe arrangement of the bricks in successive courses to tie the brick work togetherboth longitudinally and transversely. The arrangement is usually designed to ensurethat no vertical joint of one course is exactly over the one in the next course above orbelow it, and there is greatest possible amount of lap.

8.2 Bricks used in the masonry may be of the following typeThe Common Burnt Clay Bricks


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It shall be hand moulded or machine moulded. They shall be free from nodules offree lime, visible cracks, flaws warpage and organic matter, have a frog 100 mm inlength 40 mm in width and 10 mm to 20 mm deep on one of its flat sides. Bricksmade by extrusion process and brick tiles may not be provided with frogs.

Fly Ash Lime Bricks (FALG Bricks)Visually the bricks shall be sound, compact and uniform in shape free from visiblecracks, warpage, flaws and organic matter. The bricks shall be solid and with orwithout frog on one of its flat side.

Clay Fly Ash BricksThe bricks shall be sound, compact and uniform in shape and colour. Bricks shallhave smooth rectangular faces with sharp and square corners. The bricks shall befree from visible cracks, flaws, warpage, nodules of free lime and organic matter, thebricks shall be hand or machine moulded. The bricks shall have frog of 100 mm inlength 40 mm width and 10 to 20 mm deep on one of its flat sides. If made by

extrusion process may not be provided with frogs

Calcium Silicate BricksThe Calcium silicate bricks shall be sound, compact and uniform in shape. Bricksshall be free from visible cracks, warpage, organic matter, large pebbles and nodulesof free lime. Bricks shall be solid and with or without frog. The bricks shall be made offinely grounded sand siliceous rock and lime. In addition limited quantity of fly ashmay be used in the mix. These bricks are also known as Fly Ash Sand Lime bricks inthe construction industry.

Brick BatsBrick bats shall be obtained from well burnt bricks.

Mechanized Autoclave Fly Ash Lime BrickThese bricks shall be machine moulded and prepared in plant by appropriateproportion of fly ash and lime. Visually, the bricks shall be sound, compact anduniform shape, free from visible cracks, warpage and organic matters. The brick shallbe solid with or without frog, and of 100/80 mm in length, 40 mm width and 10 to 20mm deep one of its flat side. The brick shall have smooth rectangular faces withsharp corners and shall be uniform in shape and colour.

8.3 DimensionsThe brick may be modular or non-modular. Sizes for both types of bricks/tiles shallbe as per Table. While use of modular bricks/tiles is recommended, non-modular(FPS) bricks/tiles can also be used where so specified. Non-modular bricks/tiles ofsizes other than the sizes mentioned in Table may also be used where specified.

TABLEType of Bricks/ Tiles Nominal Size

mmActual Size

mmModular Bricks 200 100 100 mm 190 90 90 mm

Modular tile bricks 200 100 40 mm 190 90 40 mmNon-modular tile bricks 229 114 44 mm 225 111 44 mm


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Non-modular bricks 229 114 70 mm 225 111 70 mm

Compressive StrengthThe bricks, when tested in accordance with the procedure shall have a minimumaverage compressive strength for various classes. The compressive strength of anyindividual brick tested shall not fall below the min. average compressive strengthspecified for the corresponding class of brick by more than 20%. In casecompressive strength of any individual brick tested exceeds the upper limit for thecorresponding class of bricks, the same shall be limited to upper limit of the class forthe purpose of calculating the average compressive strength.

Water AbsorptionThe average water absorption of bricks when tested in accordance with the

procedure shall be not more than 20% by weight.

EfflorescenceThe rating of efflorescence of bricks when tested in accordance with the procedureshall be not more than moderate.

8.5 ProcedureClassificationThe brick work shall be classified according to the class designation of bricks used.

MortarThe mortar for the brick work shall be as specified, and conform to acceptedstandards. Lime shall not be used where reinforcement is provided in brick work.

Soaking of BricksBricks shall be soaked in water before use for a period for the water to just penetratethe whole depth of the bricks. Alternatively bricks may be adequately soaked instacks by profusely spraying with clean water at regular intervals for a period not lessthan six hours. The bricks required for masonry work using mud mortar shall not besoaked. When the bricks are soaked they shall be removed from the tank sufficientlyearly so that at the time of laying they are skin-dry. Such soaked bricks shall be

stacked on a clean place where they are not again spoiled by dirt earth etc.

LayingBricks shall be laid in English Bond unless otherwise specified. For brick work in halfbrick wall, bricks shall be laid in stretcher bond. Half or cut bricks shall not be usedexcept as closer where necessary to complete the bond. Closers in such cases, shallbe cut to the required size and used near the ends of the wall. Header bond shall beused preferably in all courses in curved plan for ensuring better alignment.All loose materials, dirt and set lumps of mortar which may be lying over the surfaceon which brick work is to be freshly started, shall be removed with a wire brush andsurface wetted. Bricks shall be laid on a full bed of mortar, when laying, each brick

shall, be properly bedded and set in position by gently pressing with the handle of atrowel. Its inside face shall be buttered with mortar before the next brick is laid and


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pressed against it. Joints shall be fully filled and packed with mortar such that nohollow space are left inside the joints.The walls shall be taken up truly in plumb or true to the required batter wherespecified. All courses shall be laid truly horizontal and all vertical joints shall be trulyvertical. Vertical joints in the alternate course shall come directly one over the other.

Quoin, Jambs and other angles shall be properly plumbed as the work proceeds.All quoins shall be accurately constructed and the height of brick courses shall bekept uniform.This will be checked using graduated wooden straight edge or storey rod indicatingheight of each course including thickness of joints. The position of damp proofcourse, window sills, bottom of lintels, top of the wall etc. along the height of the wallshall be marked on the graduated straight edge or storey rod. Acute and obtusequoins shall be bonded, where practicable in the same way as square quoins.Obtuse quoins shall be formed with squint showing three quarters brick on one faceand quarter brick on the other.

Finishing of JointsThe face of brick work may be finished flush or by pointing. In flush finishing eitherthe face joints of the mortar shall be worked out while still green to give a finishedsurface flush with the face of the brick work or the joints shall be squarely raked outto a depth of 1 cm while the mortar is still green for subsequently plastering. Thefaces of brick work shall be cleaned with wire brush so as to remove any splashes ofmortar during the course of raising the brick work. In pointing, the joints shall besquarely raked out to a depth of 1.5 cm while the mortar is still green and raked jointsshall be brushed to remove dust and loose particles and well wetted, and shall belater refilled with mortar to give ruled finish. Some such finishes are flush,weathered, ruled, etc.

CuringThe brick work shall be constantly kept moist on all faces for a minimum period ofseven days. Brick work done during the day shall be suitably marked indicating thedate on which the work is done so as to keep a watch on the curing period.

Half Brick WorkBrick work in half brick walls shall be done in the same manner as described aboveexcept that the bricks shall be laid in stretcher bond. When the half brick work is tobe reinforced, 2 Nos. M.S. bars of 6 mm dia. shall be embedded in every third course

as given in the item (the dia of bars shall not exceed 8 mm). These shall be securelyanchored at their end where the partitions end. The free ends of the reinforcementshall be keyed into the mortar of the main brick work to which the half brick work isjoined. The mortar used for reinforced brick work shall be rich dense cement mortarof mix 1:4 (1 cement: 4 coarse sand). Lime mortar shall not be used. Over laps inreinforcement, if any shall not be less than 30 cm.The mortar interposed between the reinforcement bars and the brick shall not beless than 5 mm. The mortar covering in the direction of joints shall not be less than15 mm.

. FLOORING


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9.1 Kota Stone FlooringKota Stone SlabsThe slabs shall be of selected quality, hard, sound, dense and homogeneous intexture free from cracks, decay, weathering and flaws. They shall be hand ormachine cut to the requisite thickness. They shall be of the colour indicated in the

drawings.The slabs shall have the top (exposed) face polished before being brought to site.The slabs shall conform to the size required.

DressingEvery slab shall be cut to the required size and shape and fine chisel dressed on thesides to the full depth so that a straight edge laid along the side of the stone shall bein full contact with it. The sides (edges) shall be table rubbed with coarse sand ormachine rubbed before paving. All angles and edges of the slabs shall be true,square and free from chippings and the surface shall be true and plane.The thickness of the slab after it is dressed shall be 20, 25, 30 or 40 mm as

specified in the description of the item.

Preparation of Surface and LayingBase concrete or the RCC slab on which the slabs are to be laid shall be cleaned,wetted and mopped. The bedding for the slabs shall be with cement mortar 1:4 (1cement : 4 coarse sand) or as given in the description of the item.The average thickness of the bedding mortar under the slab shall be 20 mm and thethickness at any place under the slab shall be not less than 12 mm.

The slabs shall be laid in the following mannerMortar of the specified mix shall be spread under the area of each slab, roughly tothe average thickness specified in the item. The slab shall be washed clean beforelaying. It shall be laid on top, pressed, tapped with wooden mallet and brought tolevel with the adjoining slabs. It shall be lifted and laid aside. The top surface of themortar shall then be corrected by adding fresh mortar at hollows. The mortar isallowed to harden a bit and cement slurry of honey like consistency shall be spreadover the same at the rate of 4.4 kg of cement per sqm. The edges of the slab alreadypaved shall be buttered with grey or white cement with or without admixture ofpigment to match the shade of the marble slabs as given in the description of theitem.The slab to be paved shall then be lowered gently back in position and tapped with

wooden mallet till it is properly bedded in level with and close to the adjoining slabswith as fine a joint as possible.Subsequent slabs shall be laid in the same manner. After each slab has been laid,surplus cement on the surface of the slabs shall be cleaned off. The flooring shall becured for a minimum period of seven days. The surface of the flooring as laid shall betrue to levels, and, slopes. Joint thickness shall not be more than 1 mm.Due care shall be taken to match the grains of slabs which shall be selected

judiciously having uniform pattern of Veins/streaks.The slabs shall be matched as shown in drawings.Slabs which are fixed in the floor adjoining the wall shall enter not less than 12 mmunder the plaster skirting or dado. The junction between wall plaster and floor shall

be finished neatly and without waviness.


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The specification shall be as described above except that the edges of the slabs tobe jointed shall be buttered with grey cement, with admixture of pigment to match theshade of the slab. The thickness of the joints should be minimum as possible. In anylocation, it shall not exceed 1 mm.

Curing, Polishing and FinishingThe day after the tiles are laid all joints shall be cleaned of the grey cement groutwith a wire brush or trowel to a depth of 5 mm and all dust and loose mortar removedand cleaned. Joints shall then be grouted with grey or white cement mixed with orwithout pigment to match the shape of the topping of the wearing layer of the tiles.The surface shall thereafter be grounded evenly with machine fitted with coarsegrade carborundum (No. 60). Water shall be used profusely during grinding. Aftergrinding the surface shall be thoroughly washed to remove all grinding mud, cleanedand mopped. It shall then be covered with a thin coat of grey or white cement, mixedwith or without pigment to match the colour of the topping of the wearing surface inorder to fill any pin hole that appear. The surface shall be again cured. The second

grinding shall then be carried out with machine fitted with fine grade grit block (No.120). The final grinding with machine fitted with the finest grade grit blocks (No. 320)shall be carried out the day after the second grinding or before handing over thefloor.After the final polish, oxalic acid shall be dusted over the surface at the rate of 33 gmper square metre sprinkled with water and rubbed hard with a namdah block (pad ofwoollen rags). The following day the floor shall be wiped with a moist rag and driedwith a soft cloth and finished clean.If any tile is disturbed or damaged, it shall be refitted or replaced, properly jointedand polished.The finished floor shall not sound hollow when tapped with a wooden mallet

9.2 Kota Stone in Risers of Steps, Skirting and DadoThe slabs shall be of selected quality, hard, sound, dense and homogeneous intexture free from cracks, decay, weathering and flaws. They shall be hand ormachine cut to the requisite thickness. They shall be of the colour indicated in the.The slabs shall have the top (exposed) face polished before being brought to site,unless otherwise specified. The slabs shall conform to the size required.Every slab shall be cut to the required size and shape and fine chisel dressed on thesides to the full depth so that a straight edge laid along the side of the stone shall bein full contact with it. The sides (edges) shall be table rubbed with coarse sand or

machine rubbed before paving. All angles and edges of the slabs shall be true,square and free from chippings and the surface shall be true and plane. Thethickness of the slab after it is dressed shall be 20, 25, 30 or 40 mm as specified inthe description of the item.Kota Stone Slabs and Dressing shall be as specified above except that thethickness of the slabs shall be 25 mm or as specified in the description of the item.The slabs may be of uniform size if required.The risers of steps and skirting shall be in grey or white cement admixed with orwithout pigment to match the shade of the stone, with the line of the slab at such adistance from the wall that the average width of the gap shall be 12 mm and at noplace the width shall be less than 10 mm, if necessary, the slabs shall be held in

position by temporary M.S. hooks fixed into the wall at suitable intervals. The skirtingor riser face shall be checked for plane and plumb and corrected. The joints shall


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thus be left to harden then the rear of the skirting or riser slab shall be packed withcement mortar 1:3 (1 cement : 3 coarse sand) or other mix as specified in thedescription of the item. The fixing hooks shall be removed after the mortar filling thegap has acquired sufficient strength.

9.3 Procedure1. Raise the level of outer wall constructed on outer beam to the level of inner beam.2. Firstly filling of murrum inside the gap of plinth beams should be done.3. Densely compaction of filling murrum and water should be sprinkled forcompaction.4. After compaction of murrum filling then filling of sand of 100mm thick layer.5. PCC is to be done over sand layer of 100mm thick for flooring work.6. Over the PCC, flooring work should be done.

Photos

10. FINISHING

10.1 Cement PlasterThe cement plaster shall be 12 mm, 15 mm or 20 mm thick as specified in the item.

ScaffoldingFor all exposed brick work or tile work double scaffolding independent of the workhaving two sets of vertical supports shall be provided. The supports shall be soundand strong, tied together with horizontal pieces over which scaffolding planks shall be

fixed.


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For all other work in buildings, single scaffolding shall be permitted. In such casesthe inner end of the horizontal scaffolding pole shall rest in a hole provided only inthe header course for the purpose. Only one header for each pole shall be left out.Such holes for scaffolding shall, however, not be allowed in pillars/columns less thanone metre in width or immediately near the skew backs of arches. The holes left in

masonry works for scaffolding purposes shall be filled and made good beforeplastering.

Preparation of SurfaceThe joints shall be raked out properly. Dust and loose mortar shall be brushed out.Efflorescence if any shall be removed by brushing and scrapping. The surface shallthen be thoroughly washed with water, cleaned and kept wet before plastering iscommenced.In case of concrete surface if a chemical retarder has been applied to the form work,the surface shall be roughened by wire brushing and all the resulting dust and looseparticles cleaned off and care shall be taken that none of the retarders is left on the

surface.

MortarThe mortar of the specified mix using the type of sand described in the item shall beused. For external work and under coat work, the fine aggregate shall conform tograding IV. For finishing coat work the fine aggregate conforming to grading zone Vshall be used.

Application of PlasterCeiling plaster shall be completed before commencement of wall plaster.Plastering shall be started from the top and worked down towards the floor. Allputlog holes shall be properly filled in advance of the plastering as the scaffolding isbeing taken down. To ensure even thickness and a true surface, plaster about 15 15 cm shall be first applied, horizontally and vertically, at not more than 2 metresintervals over the entire surface to serve as gauges. The surfaces of these gaugedareas shall be truly in the plane of the finished plaster surface. The mortar shall thenbe laid on the wall, between the gauges with trowel. The mortar shall be applied in auniform surface slightly more than the specified thickness. This shall be brought to atrue surface, by working a wooden straight edge reaching across the gauges, withsmall upward and side ways movements at a time. Finally the surface shall befinished off true with trowel or wooden float according as a smooth or a sandy

granular texture is required. Excessive troweling or over working the float shall beavoided.All corners, arrises, angles and junctions shall be truly vertical or horizontal as thecase may be and shall be carefully finished. Rounding or chamfering corners,arrises, provision of grooves at junctions etc. Such rounding, chamfering or groovingshall be carried out with proper templates or battens to the sizes required.When suspending work at the end of the day, the plaster shall be left, cut clean toline both horizontally and vertically. When recommencing the plastering, the edge ofthe old work shall be scrapped cleaned and wetted with cement slurry before plasteris applied to the adjacent areas, to enable the two to properly join together.Plastering work shall be closed at the end of the day on the body of wall and not

nearer than 15 cm to any corners or arrises. It shall not be closed on the body of thefeatures such as plasters, bands and cornices, nor at the corners of arrises.


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Horizontal joints in plaster work shall not also occur on parapet tops and copings asthese invariably lead to leakages. The plastering and finishing shall be completedwithin half an hour of adding water to the dry mortar.No portion of the surface shall be left out initially to be patched up later on. Theplastering and finishing shall be completed within half an hour of adding water to the

dry mortar.

ThicknessWhere the thickness required as per description of the item is 20 mm the averagethickness of the plaster shall not be less than 20 mm whether the wall treated is ofbrick or stone. In the case of brick work, the minimum thickness over any portion ofthe surface shall be not less than 15 mm while in case of stone work the minimumthickness over the bushings shall be not less than 12 mm.

CuringCuring shall be started as soon as the plaster has hardened sufficiently not to be

damaged when watered. The plaster shall be kept wet for a period of at least 7 days.During this period, it shall be suitably protected from all damages. The dates onwhich the plastering is done shall be legibly marked on the various sections plasteredso that curing for the specified period thereafter can be watched.

FinishThe plaster shall be finished to a true and plumb surface and to the proper degree ofsmoothness as required. The work shall be tested frequently as the work proceedswith a true straight edge not less than 2.5 m long and with plumb bobs. All horizontallines and surfaces shall be tested with a level and all jambs and corners with a plumbbob as the work proceeds.

PrecautionAny cracks which appear in the surface and all portions which sound hollow whentapped, or are found to be soft or otherwise defective, shall be cut out in rectangularshape and redone.(i) When ceiling plaster is done, it shall be finished to chamfered edge at an angle atits junction with a suitable tool when plaster is being done. Similarly when the wallplaster is being done, it shall be kept separate from the ceiling plaster by a thinstraight groove not deeper than 6 mm drawn with any suitable method with the wallwhile the plaster is green.

(ii) To prevent surface cracks appearing between junctions of column/beam andwalls, 150 mm wide chicken wire mesh should be fixed with U nails 150 mm centre tocentre before plastering the junction. The plastering of walls and beam/column in onevertical plane should be carried out in one go.6 MM Cement Plaster for Slab BearingCement plaster shall be 6 mm thick finished with a floating coat of neat cement andthick coat of lime wash on top of walls for bearing of slabs.

ApplicationThe plaster shall be applied over the cleaned and wetted surface of the wall. Whenthe plaster has been brought to a true surface with the wooden straight edge it shall

be uniformly treated over its entire area with a paste of neat cement and rubbedsmooth, so that the whole surface is covered with neat cement coating. The quantity


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of cement applied for floating coat shall be 1 kg per sqm. Smooth finishing shall becompleted with trowel immediately and in no case later than half an hour of addingwater to the plaster mix.When suspending work at the end of the day, the plaster shall be left, cut clean toline both horizontally and vertically. When recommencing the plastering, the edge of

the old work shall be scrapped cleaned and wetted with cement slurry before plasteris applied to the adjacent areas, to enable the two to properly join together.Plastering work shall be closed at the end of the day on the body of wall and notnearer than 15 cm to any corners or arrises. It shall not be closed on the body of thefeatures such as plasters, bands and cornices, nor at the corners of arrises.Horizontal joints in plaster work shall not also occur on parapet tops and copings asthese invariably lead to leakages. The plastering and finishing shall be completedwithin half an hour of adding water to the dry mortar.No portion of the surface shall be left out initially to be patched up later on. Theplastering and finishing shall be completed within half an hour of adding water to thedry mortar.

Lime washThis shall be applied in a thick coat after curing the plaster for three days.

10.3 White Washing with WhitingPreparation of MixWhiting (ground white chalk) shall be dissolved in sufficient quantity of warm waterand thoroughly stirred to form a thin slurry which shall then be screened through aclean coarse cloth. Two kg of gum and 0.4 kg of copper sulphate dissolvedseparately in hot water shall be added for every cum of the slurry which shall then bediluted with water to the consistency of milk so as to make a wash ready for use.

10.4 Oil Emulsion (Oil Bound) Washable DistemperingMaterialsOil emulsion (Oil Bound) washable distemper of approved brand and manufactureshall be used. The primer where used as on new work shall be cement primer ordistemper primer. These shall be of the same manufacture as distemper. Thedistemper shall be diluted with water or any other prescribed thinner in a mannerrecommended by the manufacturer. Only sufficient quantity of distemper required fordays work shall be prepared.

Preparation of the SurfaceFor new work the surface shall be thoroughly cleaned of dust, old white or colourwash by washing and scrubbing. The surface shall then be allowed to dry for at least48 hours. It shall then be sand papered to give a smooth and even surface. Anyunevenness shall be made good by applying putty, made of plaster of paris mixedwith water on the entire surface including filling up the undulations and then sandpapering the same after it is dry.Pitting in plaster shall be made good with plaster of paris mixed with the colour to beused. The surface shall then be rubbed down again with a fine grade sand paper and

made smooth. A coat of the distemper shall be applied over the patches. The


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patched surface shall be allowed to dry thoroughly before the regular coat ofdistemper is applied.

ApplicationPriming Coat

The priming coat shall be with distemper primer or cement primer, as required in thedescription of the item.In the case of new work, the treatment shall consist of a priming coat of whitingfollowed by the application of two or more coats of distemper till the surface showsan even colour.

The application of each coat shall be as followsThe entire surface shall be coated with the mixture uniformly, with proper distemperbrushes (ordinary white wash brushed shall not be allowed) in horizontal strokesfollowed immediately by vertical ones which together shall constitute one coat. Thesubsequent coats shall be applied only after the previous coat has dried. The

finished surface shall be even and uniform and shall show no brush marks.Enough distemper shall be mixed to finish one room at a time. The application of acoat in each room shall be finished in one operation and no work shall be started inany room, which cannot be completed the same day.After each days work, the brushes shall be washed in hot water and hung down todry. Old brushes which are dirty or caked with distemper shall not be used.

Note: If the wall surface plaster has not dried completely, cement primer shall beapplied before distempering the walls. But if distempering is done after the wallsurface is dried completely, distemper primer shall be applied.Oil bound distemper is not recommended to be applied, within six months of thecompletion of wall plaster. However, newly plastered surfaces if required to bedistempered before a period of six months shall be given a coat of alkali resistantpriming Paint and allowed to dry for atleast 48 hours before distempering iscommenced.

Distemper CoatFor new work, after the primer coat has dried for at least 48 hours, the surface shallbe lightly sand papered to make it smooth for receiving the distemper, taking care notto rub out the priming coat. All loose particles shall be dusted off after rubbing. Onecoat of distemper properly diluted with thinner (water or other liquid as stipulated by

the manufacturer) shall be applied with brushes in horizontal strokes followedimmediately by vertical ones which together constitutes one coat. The subsequentcoats shall be applied in the same way. Two or more coats of distemper as are foundnecessary shall be applied over the primer coat to obtain an even shade. A timeinterval of at least 24 hours shall be allowed between successive coats to permitproper drying of the preceding coat.15 cm double bristled distemper brushes shall be used. After each days work,brushes shall be thoroughly washed in hot water with soap solution and hung downto dry. Old brushes which are dirty and caked with distemper shall not be used on thework.

10.5 Exterior Painting on WallMaterial


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The paint shall be (Texured exterior paint/Acrylic smooth exterior paint/premiumacrylic smooth exterior paint) of approved brand and manufacture.

Preparation of SurfaceFor new work, the surface shall be thoroughly cleaned off all mortar dropping, dirt

dust, algae, fungus or moth, grease and other foreign matter of brushing andwashing, pitting in plaster shall make good, surface imperfections such as cracks,holes etc. should be repaired using white cement. The prepared surface shall havereceived the approval after inspection before painting is commenced.

ApplicationBase coat of water proofing cement paintAll specifications in respect of base coat of water proofing cement paint shallbe as described belowThe solution shall be applied on the clean and wetted surface with brushes orspraying machine. The solution shall be kept well stirred during the period of

application. It shall be applied on the surface which is on the shady side of thebuilding so that the direct heat of the sun on the surface is avoided. The completedsurface shall be watered after the days work.The second coat shall be applied after the first coat has been set for at least 24hours. Before application of the second or subsequent coats, the surface of theprevious coat shall not be wetted.For new work, the surface shall be treated with three or more coats of water proofcement paint as found necessary to get a uniform shade.Before pouring into smaller containers for use, the paint shall be stirred thoroughly inits container, when applying also the paint shall be continuously stirred in the smallercontainers so that its consistency is kept uniform. Dilution ratio of paint with potablewater can be altered taking into consideration the nature of surface climate. In allcases, the manufacturers instructions shall be followed meticulously.The lids of paint drums shall be kept tightly closed when not in use as by exposureto atmosphere the paint may thicken and also be kept safe from dust.Paint shall be applied with a brush on the cleaned and smooth surface. Horizontalstrokes shall be given, First and vertical strokes shall be applied immediatelyafterwards. This entire operation will constitute one coat. The surface shall befinished as uniformly as possible leaving no brush marks.

Precaution

Water proof cement Paint shall not be applied on surfaces already treated with whitewash, colour wash, distemper dry or oil bound, varnishes, Paints etc. It shall not beapplied on gypsums, wood and metal surfaces.If water proofing cement is required to be applied on existing surface, previouslytreated with white wash, colour wash etc., the surface shall be thoroughly cleaned byscrapping off all the white wash, colour wash etc. completely. Thereafter, a coat ofcement primer shall be applied followed by two or more coat of water proof cement.

10.6 PaintingMaterialsPaints, oils, varnishes etc. of approved brand and manufacture shall be used. Only

ready mixed Paint (Exterior grade) as received from the manufacturer without anyadmixture shall be used.


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Commencing WorkFirstly inspection of the surface is to be done. Painting of external surface should notbe done in adverse weather condition like hail storm and dust storm.Painting, except the priming coat, shall generally be taken in hand after practically

finishing all other building work.The rooms should be thoroughly swept out and the entire building cleaned up, atleast one day in advance of the Paint work being started.

Preparation of SurfaceThe surface shall be thoroughly cleaned and dusted off. All rust, dirt, scales, smokesplashes, mortar droppings and grease shall be thoroughly removed before paintingis started.

Application

Before pouring into smaller containers for use, the Paint shall be stirred thoroughlyin its containers, when applying also, the Paint shall be continuously stirred in thesmaller containers so that its consistency is kept uniform.The painting shall be laid on evenly and smoothly by means of crossing and layingoff, the latter in the direction of the grains of wood. The crossing and laying offconsists of covering the area over with Paint, brushing the surface hard for the firsttime over and then brushing alternately in opposite direction, two or three times andthen finally brushing lightly in a direction at right angles to the same. In this process,no brush marks shall be left after the laying off is finished. The full process ofcrossing and laying off will constitute one coat.Where so stipulated, the painting shall be done by spraying. Spray machine usedmay be (a) high pressure (small air aperture) type, or (b) a low pressure (large airgap) type, depending on the nature and location of work to be carried out. Skilled andexperienced workmen shall be employed for this class of work. Paints used shall bebrought to the requisite consistency by adding a suitable thinner.Spraying should be done only when dry condition prevails. Each coat shall beallowed to dry out thoroughly and rubbed smooth before the next coat is applied.This should be facilitated by thorough ventilation. Each coat except the last coat,shall be lightly rubbed down with sand paper or fine pumice stone and cleaned offdust before the next coat is laid.No left over Paint shall be put back into the stock tins. When not in use, the

containers shall be kept properly closed.No hair marks from the brush or clogging of Paint puddles in the corners of panels,angles of mouldings etc. shall be left on the work.In painting doors and windows, the putty round the glass panes must also be paintedbut care must be taken to see that no Paint stains etc. are left on the glass. Tops ofshutters and surfaces in similar hidden locations shall not be left out in painting.However, bottom edge of the shutters where the painting is not practically possible,need not be done nor any deduction on this account will be done but two coats ofprimer of approved make shall be done on the bottom edge before fixing theshutters.On painting steel work, special care shall be taken while painting over bolts, nuts,

rivets overlaps etc.


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The additional specifications for primer and other coats of Paints shall be asaccording to the detailed specifications under the respective headings.

Brushes and ContainersAfter work, the brushes shall be completely cleaned of Paint and linseed oil by

rinsing with turpentine. A brush in which Paint has dried up is ruined and shall on noaccount be used for painting work. The containers when not in use, shall be keptclosed and free from air so that Paint does not thicken and also shall be kept safefrom dust. When the Paint has been used, the containers shall be washed withturpentine and wiped dry with soft clean cloth, so that they are clean, and can beused again.

10.7 Wall Painting with Plastic Emulsion PaintThe plastic emulsion Paint is not suitable for application on external, wood and ironsurface and surfaces which are liable to heavy condensation. These Paints are to beused on internal surfaces except wooden and steel.

Painting on New SurfaceThe surface shall be thoroughly cleaned and dusted off. All rust, dirt, scales, smokesplashes, mortar droppings and grease shall be thoroughly removed before paintingis started.

ApplicationThe number of coats shall be as stipulated in the item. The Paint will be applied inthe usual manner with brush, spray or roller. The Paint dries by evaporation of thewater content and as soon as the water has evaporated the film gets hard and thenext coat can be applied. The time of drying varies from one hour on absorbentsurfaces to 2 to 3 hours on non-absorbent surfaces.The thinning of emulsion is to be done with water and not with turpentine. Thinningwith water will be particularly required for the under coat which is applied on theabsorbent surface. The quantity of water to be added shall be as per manufacturersinstructions.The surface on finishing shall present a flat velvety smooth finish. If necessary morecoats will be applied till the surface presents a uniform appearance.

Precautions(a) Old brushes if they are to be used with emulsion Paints, should be completelydried of turpentine or oil Paints by washing in warm soap water.Brushes should be quickly washed in water immediately after use and keptimmersed in water during break periods to prevent the Paint from hardening on thebrush.(b) In the preparation of wall for plastic emulsion painting, no oil base putties shall beused in filling cracks, holes etc.(c) Splashes on floors etc. shall be cleaned out without delay as they will be difficultto remove after hardening.(d) Washing of surfaces treated with emulsion Paints shall not be done within 3 to 4

weeks of application.


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