good construction practices –part i - acc...

Good Construction Practices – Part I

This report is solely for the internal use. No part of it may be circulated, quoted, or reproduced for distribution outside the company organization without prior written

approval from ACC Limited. This material was used during an oral presentation; it is not a complete record of the discussion.

� Cost Estimation and budgeting� Layout planning, drawing preparation & approval� Excavation, foundation, plinth beam or brickwall up to plinth, DPC, compound wall

� Brick wall up to roof, lintels & Chajjas and openings for doors/ windows, septic tankShuttering for slab, reinforcement fixing, concreting

Construction Sequence of a House

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ACC Limited 26.06.2010Good construction practices

� Shuttering for slab, reinforcement fixing, concreting� Electrical conduit, Plastering work, floor concreting & roof water proofing, water supply & sanitary pipe fixing

� Floor tiles, painting, electrical wiring, fittings in bath/kitchen, door & window shutters, electrical fittings

� Plinth protection, final painting, check list, billing

Estimation of Material Requirements

� For M-20 grades of concrete of 1 cu. m.

� Cement 6.5-7.5 bags, Sand- 0.4m3 , CA- 0.83m3 , water 21-22 litre

� For 100sq.m (1076 sq. ft.) Slab of 4” thk-

� Cement 79 bags, Sand- 4.2m3 , CA- 8.3m3 ,

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� For plaster of 100 sq. m.

Cement Sand

� 1:4 ( 12mm thk) 12 bags 1.6m3

� 1:4 ( 20mm thk) 20 bags 2.6m3

� 1:6 ( 12mm thk) 9 bags 1.8m3

� 1:6 ( 20mm thk) 12 bags 3.0m3

� For brick works of 1 cu. M.- 500 bricks are required.

� Formwork should be watertight so that there is no loss of cement paste through it.

� Properly leveled centering will minimize the cost of finishing� Supports should be provided to slab and beam at sufficient

distance.� Apply a mixture of Greece and diesel before using.

Centering (FORMWORK)

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Formwork

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Why cover blocks?

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Do not use of Aggregates as Cover Blocks

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Cover Blocks for Durability

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Cover Blocks

� Use Proper Cover Blocks

� As per IS, cover should be

� 40mm for columns� 25 mm for columns of minimumdimension of 200 mm or under

� 50 mm for Footing

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ACC Limited 26.06.2010Good construction practices

� 50 mm for Footing� 30mm for moderate exposure� 20mm for mild exposure ( 15mmif bars of 12mm dia are used)

Control Slump

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� Avoid Manual concrete mixing.

� Keep a close watch on water quantity while mixing

� Minimum mixing time should be 2 mins.

� Use Admixtures only if required.

� Admixture dosage should be optimum. Do not add more/less quantity.

Concrete Mixing

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� Admixture should be first added in water and then can be mixed with other ingredients.

� Mortal Plasticizer should be used only for Mortar and concrete plasticizer for concrete.

� Use good quality Water proofing chemical which should be chloride free.

� For RCC minimum grade of concrete should be M 20

Add Water

by

Measurement

Water

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ACC Limited 26.06.2010Good construction practices

at

Construction

Site

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ACC Limited 26.06.2010Good construction practices

Avoid

Segregation

&

Segregation & Bleeding

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ACC Limited 26.06.2010Good construction practices

bleeding

of

concrete

Segregation

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ACC Limited 26.06.2010Good construction practices

� Concrete should be poured from more than 1 m height to avoid segregation.

� Walking rails should be provided on slabs before concrete placement so that R/F will not get disturbed/damaged.

Placing of Concrete

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height to avoid segregation.

� Compaction means removing air from concrete

� It will reduce the voids

� Lesser the voids, stronger the concrete.

Compaction

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the concrete.

� Proper compaction will ensure Water tightness

� For manual compaction of slab use Wooden float and 16 mm bar

Compaction

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ACC Limited 26.06.2010Good construction practices