raft foundation f

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2. CAST IN-SITU WORKS

2.1 INTRODUCTION

This chapter include details about construction of raft foundation and construction of

shear wall.

Construction of raft foundation and shear wall include tender specifications, material

specifications, tools-plants and equipment used, enabling works, manpower employed,

productivity and cost aspects, bar bending schedule etc.

2.2 RAFT FOUNDATION CONSTRUCTION

2.2.1 TENDER SPECIFICATIONS

1. Materials for standard concrete

(a) Cement

Unless otherwise specified, cement shall be OPC in 50kg bags.

Changing of brands or type or cement within same structure is not permitted.

A certified report attesting the conformity of cement to IS from cement manufacturers

chemist shall be furnished to the Engineer, However, Cement will be tested before use by

contractor at his own cost in concrete testing laboratory.

Cement may be stored in bins or silos which provides protection from dampness

contamination & false set.

Cement bags shall be stored in dry enclosed shed well away from outer walls & insulated

from floor to avoid contact with moisture from ground & not more than 12 bags shall be

stacked in any tier.

Cement had in storage for a period of 90 days or longer shall be tested.

The cement shall be tested once in beginning for every brand of cement for structural use

and thereafter at every 250 MT of cement consumed.

The frequency will be reduced to one cement test for every 500 MT consumed after 50%

of RCC is over.

It is required that for every track load, the manufacture has to give test certificate.

(b) Aggregates

Fine aggregates are those which pass through 4.75 mm is sieve & those which are retained

are coarse.

After specific material has been accepted the source of supply shall not be change without

approval of the engineer.

Aggregates shall be chemically inert, hard, durable against weathering of limited porosity

& free from deleterious material which may impair the concrete or reinforcement.

Samples of aggregates for mix design & determination of suitability shall be taken under

the supervision of engineer & delivered to laboratory.

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Record of tested on proposed aggregates on concrete made from this source of aggregates

shall be furnished to Engg. in advance of work for determining suitability.

All course & Fine aggregates shall be stacked separately in stock piles. Contamination with

foreign material while heaping shall be avoided.

Racers shall be used for lifting coarse aggregates from piles.

Coarse aggregates shall be piled in layers not exceeding 10 meter in height to prevent

coning each layer shall be cover the entire stocking area.

Aggregates having specific gravity less than 2.6 (Saturated surface dry basis) shall not be

used.

Fine aggregates shall consist of natural or crashed sand conforming to IS 383.

The sand shall be free from deleterious substance.

Silt content in sand will be measured by volume for every truck load before unloading.

Machine made sand will be acceptable, provided the constituent gravel / rock composition

is sound, hard, dense, non-organic, uncoated & durable against weathering.

Sand shall be prepared for use by careening to remove all objectionable foreign &

deleterious material.

The percentage of deleterious matter in sand delivered to mixer shall not exceed following:

Table 2.1.1 Limiting values of deleterious matter in sand

Materials Percent by weight

Uncrushed Crushed

material finer than 75 micron size 3 15

Shall 1

Coal & Lignite 1 1

Clay lumps 1 1

Total of all above substances

Including items (i) to (iv)

For uncrushed & (iii) & (iv)

For crushed sand

5 2

Where the grading falls outside limits of any particular grading zone of sieve (except 600

micron sieves) by a total amount not exceeding 5%, it shall be regarded as falling within

that zone.

This tolerance shall not be applied to % passing 600 micron sieve or to % passing any other

sieve size on the coarser limit of zone I or finer limit or zone IV.

Fine aggregates conforming to grading zone IV shall not be used.

Table 2.1.2 Zone distribution of sand

Is sieves

Designation

Zone I

(% passing)

Zone II

(% passing)

Zone III

(% passing)

Zone IV

(% passing)

10mm 100 100 100 100

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

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9.36mm 60-95 75-100 85-100 95-100

1.18mm 30-70 55-90 75-100 90-100

600 15-34 35-59 60-79 80-100

300 5-20 8-30 10-40 15-50

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

The sand shall have a fineness modulus of not less than 9.9 or more than 3.9, Fineness

modulus is determined by adding cumulative % on following is sieves: 4.75mm, 9.36mm,

1.18mm, 600, 300, 150 & dividing sum by 100.

Coarse aggregates shall consist of natural or crushed stone or gravel & shall be clean &

free from alkali & organic deleterious matter.

Table 2.1.3 Foreign material limitations for coarse aggregate

Material Percent by weight

Uncrushed Crushed

material finer than 75 micron 3 3

Coal 1 1

clay lumps 1 1

Soft fragments 3

Total 8 5

Pieces shall be angular & shall have granular surface.

The maximum size of coarse aggregate shall be 40mm for class A concrete & 90mm for

class B concrete.

Plums above 160 mm & upto any reasonable size may be used in PCC of large dimensions

upto a maximum limit of 90 % by volume of concrete.

After 24 hours immersion in water, a previously dried sample shall not have gained more

than 10% of its oven dry weight in air.

The amount of fine particles in loose state shall not exceed 1%.

Table 2.1.4 % Passing for single and graded coarse aggregate

Is sieve

designation

% passing for single size aggregate of

nominal size

% passing for graded aggregate of

nominal size

40 20 16 12.5 10 40 20 16 12.5

63 mm 100 100

40mm 85-100 100 90-100 100

20mm 0-20 85-100 100 30-37 90-100 100

16mm 85-100

12.5mm 85-100 90-100

10mm 0-20 0-30 0-45 85-100 10-35 25-55 30-70 40-85

4.75mm 0-5 0-5 0-10 0-20 0-5 0-10 0-10 0-10

2.36mm

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(c) Water

Water used for mixing & curing shall be free from injurious matter, potable water is

generally considered satisfactory.

In case of doubt, suitability of water shall be found by compressive strength & initial setting

time test.

The sample of water taken for testing shall be typical of the water proposed for concrete.

An average of 28 days compressive strength of three 150mm concrete cubes prepared with

proposed water shall not be less than 90% of equivalent cubes made using distilled water.

The initial setting time of test blocks shall not be less than 30 minutes & not differ by more

than 3 minutes from that made from distilled water.

The percentage of solids in water is as follow :

Table 2.1.1 Limiting values for solids in water

Matter / solids Percent

Organic 0.09

Inorganic 0.3

Sulphates (So4) 0.05

Alkali chlorides 0.9

(d) Admixtures

Admixtures may be used in concrete provided that with passage of time, neither

compressive strength nor durability will be reduced. These shall be used in accordance with

manufactures instructions.

Water reducing lignosulphate admixtures shall be added in the form of solution if used.

Where specified & approved by engineer retarding agents may be added to concrete.

2. Reinforcement

Steel reinforcement shall be plain round M.S. bars in accordance with IS 432-I or medium

tensile steel bars in accordance with IS 432-II or hot rolled M.S. and medium tensile

deformed bars in accordance with is IS 1139 or cold twisted bars in accordance with IS

1786.

(a) Storage

Steel reinforcement shall not be kept in direct contact with ground but stocked on top of

timber sleeper. If the reinforcing bars are to be stored for long duration they be water with

cement wash before stacking.

(b) Quality

Before structural work commences all diameter of steel bar to be tested, In case of TOR

steel, each diameter bar to be tested be free from grease, oil, paint, dust, bitumen etc. which

reduce, destroy the bond.

No welding of bars to attain continuity shall be allowed.

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In case of TMT steel for diameter 8, 10, & 12 on consumption of 50 MT of each dia. and

for diameter 16, 20, 25 on consumption of 30 MT, test shall be conducted.

(c) Laps, Bending & Fixing

Laps & splices shall be shown on the drawing and the bar bending schedules splices shall

be staggered in adjacent bars locations shall be approved by engineer.

No laps to be provided unless length exceeds minimum available length.

All bars shall be accurately bent according to sizes & shapes shown on drawing or bar

bending schedules.

Reinforcing bars shall not be straightened and re-bent in a manner that will injure material.

No reinforcement shall be bent when in position in the work cut-out approval of engineer.

Bars shall be bent cold and those having kinks other than required by design shall not be

used.

Reinforcement shall accurately fixed & maintained in the correct position by the use of

chairs, cover blocks to prevent displacement during placing & compaction of concrete.

Bars intended to be in contact at crossing points shall be bound together by no.16 gauge

annealed soft iron wire.

Dowels must be left straight and not bent by 90 degree to avoid making holes in form work.

Cover to the reinforcement shall be as given in the drawing.

(d) Payment

For the payment of works under this item the actual quantities of steel embedded in concrete

as calculated shall be taken.

Quoted rates shall include all wastage, binding wires etc. For which no separate payment

shall be made.

An unaccountable wastage of 3% shall be allowed for reconciliation only.

3. Controlled Concrete

All concrete used in works shall be Controlled Concrete unless nominal mix such as

1:3:6, 1:4:8 or 1:5:10.Minimum compressive strength of 15 cm cubes at 28 days after

mixing (IS 456 & IS 516) is as follows.

Table 2.1.2 Minimum compressive strength of concrete at 28 days

Grade

(N/mm2)

Assumed standard

deviation (Is 456)

(N/mm2)

Avg. field strength

target strength

(N/mm2)

Recommended

laboratory

strength (N/mm2)

30 6 38.1 43

35 5.3 43.5 50

40 5.6 48.9 56

The total aggregate by weight / 50kg of cement shall not exceed 450kg, except when

permitted by engineer.

If 28 days cube strength for certain structures is below IS456 requirement then payment to

the contractor will be made for lower grade achieved.

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(a) Mix Design

The mix proportion shall be determined by weight adjustment due to moisture present in

aggregates shall be made.

Mix design shall be carried according to ACI 613 or Design of concrete mixes Road

research note no.4, Department of scientific & industrial research, UK.

Whenever there is change in required strength or workability or source of material,

preliminary test shall be repeated to determine revised proportions.

While fixing values for W/C ratio for preliminary mixes, assistance may be derived from

graph (Appendix A, IS 456) showing relationship between 28 days compression strength

& W/C ratio.

(b) Preliminary tests

Test specimen shall be prepared with at least two different W/C ratio for each class of

concrete consistent with the workability required for nature of work.

The object of these tests is to determine the propositions of cement of required consistency

& strength.

4. Proportioning , Consistency, Batching & Mixing of Concrete

(a) Aggregates

Proportioning decided by conducting preliminary tests shall be by weight.

The proportions of cement, fine & coarse aggregates shall be maintained during subsequent

concrete batching by being batches (IS 24722) capable controlling weights within 1%.

The grading of aggregates shall be checked frequently to ensure the maintaining of grading

in accordance with the sample used in preliminary mix design.

The crushing strength shall be tested:

o At start of project

o Six month after the start of project

o Whenever the source is changed

Further sieve analysis shall be carried out

o At start of project

o Every once in 2 weeks.

(b) Cement

Cement shall be measured by weight.

(c) Water

The water added to the mix shall be such as not to cause segregation of material or

collection of excessive free water on the surface of concrete.

Chemical testing shall be done,

o Once at the start of project.

o Once during summer for bore well water.

o For tank water, once every month.

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The water content in aggregates shall be determined frequently and the mixing water shall

be adjusted according to maintain specified w/c ratio.

(d) Consistency & slump

Concrete shall be of workability suitable for work. After amount of water has been

determined, the consistency shall be maintained by conducting slump test and compactor

factor tests.

Slump for various type of contraction.

Table 2.1.3 Slump for different types of construction

Type of construction Slump (mm)

Max Min

Reinforced foundation walls & footing 75 25

Slabs, Beams & Reinforced walls 100 25

Building columns 100 25

(e) Batching & Mixing

The material proportion established by preliminary tests shall be strictly followed.

The accuracy of weight batches be checked periodically.

The needle shall be adjusted to zero when hopper is empty, volume batching is not

permitted.

However, Engineer may permit volume batching by conversion of weights into equivalent

volumes knowing their bulk densities only in small pools not more than 0.25 m3 when

other pours through weigh batching are not likely to be made.

Each batch shall be mixed until the concrete is uniform in colour for a minimum period of

2 minutes after all materials & water are in drum. All water shall be in the drum by the

end of first 15 second of mixing time.

Each time the batches stops, mixes shall be cleaned & when next commencing mixing, the

first batch shall have 10 % additional cement to allow sticking to drum.

5. Sampling for strength of concrete

At least six test cubes of concrete shall be made for every 150 m3 of concrete or part

thereof.

Such samples shall be drawn on each day for each type of concrete.

Of each set of six cubes 3 shall be tested at 7 days & 3 at 28 days.

The engineer will approve the concrete if average strength of specimens is not less than

specified strength subjected to the condition that only one out of 3 consecutive tests may

have valve less than specified but not less than 90% of specified.

Slump tests shall be invariably carried out from the same batch of concrete from which

test cubes are made.

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6. Load tests on Members or any other tests

All formwork shall be checked by the Employees quality assurance department.

The contractor shall initiate a system of poor cards and excavation permits before actual

work begins.

Materials other than those supplied by employer shall be procured in advance of actual so

that employees quality control can check.

In the event of any work being suspected of having been constructed using faulty material

or workmanship, it should be load tested with following provisions :

o Test loads shall be 125% of max superimposed load for which structure was designed

such load shall not be applied 56 days after the effective hardening of concrete , during

the test starts strong enough to take whole load shall be placed in position under the

members. Test load shall be maintained for 24 hrs.

o If within 24 hours of removal of load, the structure does not show recovery of at least

75% of maximum deflection shown, loading shall be repeated after a lapse of 72 hrs.

The Structure shall be considered to have failed if recovery after 2nd test is not at least

75 % of max deflection shown during 2nd test.

Any other test, e.g. Concrete cores, examination & tests on such cores, sonic testing etc.

7. Preparation prior to concrete placement

Before concrete placing the insides of formwork should be inspected to see that they have

been cleaned & oiled.

Temporary opening shall be provided to facilitate inspection, especially at the bottom of

column & wall to forms permit removal of dust, binding wire, dirt etc.

The various trades shall be permitted times to ... drainage & plumbing lines, drains,

conduits etc.

All embedded parts, inserts etc. shall be correctly positioned & secured in the formwork to

prevent displacement during pouring and vibrating of concrete.

To guard against damage that may be caused by rains, work shall be covered with tarpaulins

immediately after concrete has been poured & compacted.

Immediately before concrete pouring begins prepared surfaces, except formwork that will

come in contact with concrete shall be covered with bonding mortar.

Irrespective of the method of transportation adopted concrete shall be delivered with

required consistency and plasticity without slump loss.

However chutes shall not be used without prior permission.

All equipment used for mixing, transporting & placing concrete shall be thoroughly cleaned

after each period of placement.

8. Procedure for pouring concrete

Equipment for concreting shall be of such size and design to ensure a practically continuous

flow of concrete during deposition without segregation of materials, considering the size

of job & placement location.

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Concrete shall be poured in its final portion before cement reaches its initial set and shall

be normally compacted in its final position within 30 minutes or learning the mixed. Once

compacted, shall not be disturbed.

Concrete shall in all cases, be deposited as nearly as practicable directly in its final position

& shall not be re-handled.

Concrete shall not be dropped from height more than 1m.

When using mechanical equipment for pouring, concrete shall be discharge by a vehicle

drop into the middle of bucket and this principle or vertical discharge shall be followed

during all stages of delivery. Central bottom-dump bucket shall be used.

The open bucket shall clear the concrete of ready placed & drop shall not exceed 1m.

Chutes when used shall have slopes not flatter than 1(vertical): 3 and not sleeper than 1(V):

2. Chutes shall be of metal and have rounded cross section. The fall of concrete from the

end of chute shall not be more than 1m.

To allow for loss of mortar against sides of chutes, the first mixes shall have coarse

aggregate.

When pumping is adopted, before pumping of concrete, the pipeline shall be lubricated

with one or two batches of mortar of one part cement & two part sand.

Concreting once started shall be continuous until the pour is completed. Concrete shall be

poured in successive horizontal layers of uniform thickness ranging from 15 to 90 m as

directed by engineer.

The thickness of each layer shall be such that it can be deposited before the previous layer

has stiffened the top surface of each pour & bedding planes shall be approximately

horizontal.

Concrete shall be compacted during placing with approved vibrating equipment till

concrete is compacted to maximum density. Particular care shall be taken to ensure that all

concrete placed against formwork faces & into corners is free from voids or cavities.

Vibration shall not be over exercised to the point that segregation results.

Immersion vibrators shall be inserted vertically at points not more than 450mm apart &

withdrawn when air bubbles cease to come to surface.

Immersion vibrators shall penetrate the layer being placed & also penetrate the layer below

while the under layer is still plastic to ensure good bond & homogeneity.

Immersion Vibrators shall not be allowed to come in contact with reinforcement steel after

the initial set.

They shall not be allowed to come in contact with formwork.

Each part of concrete in multiple light work shall be allowed to set for at least 24hrs after

final set of work & before the start of subsequent part.

When pouring concrete in walls with opening in floors of integral slab and beam

construction, pouring shall stop when the concrete reaches the top of the opening in wall

or bottom horizontal surface of the slab. Pouring shall be resumed before concrete in place

takes initial set.

Bleeding or free water on top of concrete being deposited into formwork shall be a cause

to stop the concrete pour and the condition casing this elected corrected before any further

concreting is resumed.

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When pouring concrete through steel rebars, care shall be taken to prevent segregation of

coarse aggregates.

9. Construction joint & keys

Concrete shall be poured without interruption until completion of the past of the work

between predetermined construction joints.

If stopping of concreting becomes inevitable, a properly formed construction joint shall be

made where the work is stopped.

Joints shall be horizontal or vertical or at right angles to the axis of inclined or curved

members.

Vertical joints shall be formed against stop boards.

Where not described joints shall be in accordance with following:

o Column joints

Joints shall be formed 75mm below the lowest soffit of beams including haunches. In

flat slab, construction joints shall be 75mm bellow the soffit of column capitals. At least

&2 hours shall elapse after depositing concrete in columns and before depositing in

beams or slabs.

o Beam & slab joints:

Concrete in beams shall be placed throughout without joints but if it is unavoidable,

joints shall be vertical and at the centre or within the middle third of the open. Where

beams intersects girders joints in the girders, it shall be offset a distance equal to twice

the width of beam and additional reinforcement provided for shear.

Joints in slabs shall be vertical and parallel to principal reinforcement. Where they are

unavoidably perpendicular to principle reinforcement, they shall be at the middle.

Dowels for concrete work, not likely to be taken up in near future, shall be wrapped in tar

paper.

Mass foundation shall be poured in light not exceeding 1.5m in thickness.

Treatment of construction joints on resuming: All loose stones shall be thoroughly remove

by wire brushing & hacking and surface washed. Just before concreting & is resumed, the

roughened surface shall be cleaned and treated with thin layer of cement group (1:2 by

volume proportion) and worked well into the surface. The new concrete shall be well

worked against prepares face before mortar sets.

10. Curing & protection, repairing, finishing

All concrete shall be cured by keeping it damp for the period of time required for complete

hydration and hardening to take place.

Preference shall be given to the use or continuous sprays or ponded water, continuously

saturated coverings of sacking, hessian or approved curing compounds.

Fresh concrete shall be kept continuously wet for a minimum of 10 days from date of

pouring of concrete, following a lapse of 12 to 14 hours after pouring. The curing of

horizontal surface exposed to wind shall begin immediately after the concrete has hardened.

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Water shall be applied to uniformed surface within 1 hour after concreting has set

immediately upon removal of form.

A continuous fine mist spraying or sprinkling through hose shall be used instead of

continuous spraying, wet gunny bags which prevent loss of moisture may be used.

For curing of floors, roofs, ponding method is preferred.

No curing compound shall be used on surfaces where future blending with concrete,

pointing is specified.

All sunken slabs, terrace slabs shall be tested for water tightness by flooding with water for

48 hours before waterproofing. Leaks shall be grouted either with cement grout or epoxy.

Immature concrete shall be protected from damage by debris, excessive loading or contact

with other materials and workman shall be prevented from disturbing green concrete during

jetting period.

After the removal of formwork, concrete surface shall be very carefully inspected and all

defective areas shall be patched or concrete may be rejected partially or entirely.

Holes left for formwork tie rod shall be filled up & made good with mortar composed of

1(cement): 1.5(sand) passing 2.36mm IS sieve. Mortar filling shall be flush with face of

concrete.

Surface irregularities on concrete surface shall be removed by grinding.

Superficial honey combed surface shall be similarly made good after formwork removal.

If reinforcement is exposed or honey combing is occurs at vulnerable positions, e.g. ends

of beams or columns, it may be necessary to reconstruct the member.

If only patching is necessary, defective concrete shall be cut out until solid concrete is

reached (or to a minimum depth of 25mm), the edges being cut perpendicular to affected

surface.

Anchors, tees shall be provided to attach new concrete securely in place. An area if

necessary extending several centimetres beyond edges and surface of prepared voids shall

be saturated with water for 24 hours after placing of patch material.

Epoxy use for bonding, fresh concrete used for repair shall be permitted after approval.

Small size holes having surface dimensions approximately equal to depth of hole, holes left

after removal of tie rods shall be repaired as follows,

o Holes to be patched shall be roughened & soaked with clean water until absorption

stops. A 5mm thick layer of grout of equal parts of cement and sand shall be brushed

into the surface to be patched followed by patching concrete which shall be

consolidated with wooden flat. This patch shall be built in 10mm thick layers. After an

hour, it shall be flushed with wooden flat. The concrete grade used for patching shall

be same as that of underplaying concrete.

o Mortar filling by pressure (guniting) shall be used for areas too large or too shallow for

mortar patching. While cement shall be substituted for OPC to match the shade with

concrete.

o Patched area shall be covered immediately with gunny bags which shall be kept wet for

24 hours. Thereafter cured for at least 10 days.

Formed surface finish: The type of finish for formed concrete surface shall be as follows:

o For surface against which barriers or concrete is to be placed, no treatment is required

apart from repairs.

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o For surface that will receive waterproofing shall be free of surface irregularities which

may interfere with water-proofing material.

For form finish concrete, following is required:

o Contractor shall submit detailed calculations & sketches showing entire scheme of

formwork, 1 week before starting of work.

o Plywood (12mm thick) shall not be used more than 6 times.

o Gradual irregularities shall be measured as deviations from a plane surface with a

template (6mm long) & irregularities shall not exceed 6mm.

If specified finish is not obtained, contractor will only be paid 50% of quoted rate for the

defective area.

Surface exposed to weather shall be sloped for drainage. The tops of narrow surface such

as stair tread, walls, and parapets shall be sloped approximately 1 in 30. Broader surface

such as walkways, roads shall be sloped approximately 1 in 50 across width. Surface

irregularities shall not exceed 6mm.

Exposed concrete (exposed to view) shall have smooth finish achieved through use of lined

or plywood forms having smooth & even surface.

11. Anti-termite treatment

The Indian standard codes are

o 6313(part 1): Code of practice for anti-termite treatment in building constructional

measures.

o 6313(part 2): Code of practice for anti-termite treatment in building (pre-construction

treatment)

One of the following chemicals in water emulsion shall be used.

Table 2.1.4 Anti- termite chemicals

Chemical Concentration by weight (%)

Chloropyrifos As per manufacturers instructions Indosulfon

Soil treatment should start when foundation trenches and pits are ready to take mass

concrete, laying of concrete should start when the chemical emulsion has been absorbed by

soil & surface is dry.

Once formed, treated soil barriers shall not be disturbed. If disturbed, immediate steps shall

be taken to re-attain the continuity of barriers.

The bottom surface and sides (up to height 300mm above foundation level) of excavation

basements shall be treated with chemical at the rate of 5 liters/m2.

In the case of RCC framed structures with columns & RCC basements, the treatment shall

start at the depth of 500mm below ground level, from this level, the backfill shall be treated

at the rate of 15 liters/m2 of vertical surface.

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When pipes, conduits enter the soil inside the area of foundation, the soil surrounding the

points of entry shall be loosened for a distance of 15cm & up to depth of 7.5cm before

treatment is commenced.

A pressure pump shall be used to carry out spraying operations to facilitate uniform

spraying & penetration of chemical into earth.

Tenderers must ensure that the work will be carried out through professional pest control

operators who should be members of Indian pest control association.

12. Preparation of strata of foundations

To provide light bond with rock foundations, rock surface shall be prepared as follows:

o Concrete shall not be deposited on large sloping rock surface. Rocks shall be cut form

rough steps or benches to provide roughness or suitable bearing surface.

o Rock strata shall be prepared by picking, wedging and similar methods that bear rock

in sound condition.

o Shortly before concrete is poured, rock surface shall be cleaned with high pressure

water.

o Prior to pouring, rocks surfaces shall be kept let for a period of 2 to 4 hours.

All earth surface upon which concrete is to be poured shall be well compacted and free

from water, mud or debris. The surface of absorptive soils against which concrete is to be

placed shall be moistened.

After the surface is prepared, it shall receive a bonding treatment immediately before

pouring of concrete. The bonding medium shall be a coat of cement-sand mortar. The

mortar shall have same cement-sand proportions as the concrete that shall be placed upon

it.

Bonding mortar shall be about 10mm thick for rock and 5mm thick for concrete. It shall be

worked thoroughly into all crakes & services.

In pouring concrete against formed construction joints, surfaces of joints shall be wetted

with specified bed-joint bonding mortar or by scrubbing with wire brooms dipped into fresh

concrete.

2.2.2 MATERIAL SPECIFICATIONS

1. Concrete materials

(a) Cement

Type: OPC 53 grade

Source: Ultratech OPC 53, Andhrapradesh(Tatapathre)

Rate: Rs 260/bag

Quality check: Fineness test(cement is passed through 90 sieve)

Specifications ( required as per IS):

o Fineness: 225 m2/kg

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o Setting time in minutes

Initial: 30

Final: 600

o Soundness:

Lechatelier: 10mm

Autoclave: 0.8%

o Compressive strength:

3 days: 27 Mpa

7 days: 37 Mpa

28 days: 53 Mpa

(b) Aggregates

i. Coarse aggregates (20 mm & down)

Angular crush broken coarse aggregates of max size 20mm

Source: Chikaballapura, Karnataka.

Rate: Rs 600/ton

Characteristics:

Table 2.1.9 Coarse Aggregate (20mm and down) properties

1 Shape Angular

2 Dry rodded bulk

density 1585 kg/m3

3 Loose bulk density 1386 kg/3

4 Specific gravity 2.7

5 Water absorption 0.2%

Table 2.1.10 Sieve analysis results

IS sieve Cumulative percent

Retained Passing

40mm 0 100

20mm 8.3 91.7

12.5mm 86.8 13.2

10mm 96.7 3.3

4.75mm 99.9 0.1

ii. Coarse aggregates (12.5mm & down)

Angular crusher broken coarse aggregates

Source: Chikaballapura, Karnataka.

Quality checks in Lab: Impact, crushing, Flakiness and Elongation tests for coarse

aggregates

Rate: Rs 530/ton

Characteristics:

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Table 2.1.11 Coarse Aggregate (12.5mm and down) properties

1 Shape Angular

2 Dry rodded bulk density 1513 kg/m3

3 Loose bulk density 1320 kg/m3




IS sieve Cumulative percent

Retained Passing

40mm 0 100

20mm 9.8 90.2

12.5mm 50.4 49.6

10mm 95.5 4.5

4.75mm

iii. Fine aggregates

Type: Manufactured sand

Source: Robosilicon Pvt. Ltd.

Rate: Rs 670/ton

Quality checks: Sieve analysis in laboratory

Characteristics:

Table 2.1.13 Fine aggregates properties

1 Dry rodded bulk density 1844 kg/m3

2 Loose bulk density 1706 kg/m3




IS sieves Cumulative percent

Retained Passing

4.75mm 0 100

2.36mm 14.4 85.6

1.38mm 37.3 62.7

600 microns 54.8 45.2

300 microns 73.5 26.5

150 microns 90.7 9.3

(c) Ground granulated blast furnace slag (Mineral admixture)

GGBS from JSW steel Ltd.

Source: Ballari, Karnataka.

Rate: Rs 3128/ton

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Confirms to IS 12089-1987 & BS-6699

Characteristics:

Table 2.1.15 GGBS properties

Sr. No. Characteristics

Requirement

as per BS-

6699

Test result

1 Fineness (m2/kg) 275 minimum 376

2 Particle size

(Cumulative %) 45 /90 96.15/100

3 Insoluble residue (%) 1.5 max 0.29

4 Magnesia content (%) 14.0 max 8.33

5 Sulphide sulphur (%) 2.0 max 0.49

6 Sulphur content (%) 2.5 max 0.34

7 Loss on ignition (%) 3 max 0.19

8 Manganese content (%) 2 max 0.08

9 Chloride content (%) 0.1 max 0.01

10 Glass content (%) 67 min 90

11 Moisture content (%) 1 max 0.14

12

Cao+Mgo+Sio2 66.66 min 76.24

Cao+Mgo+Sio2 >1 1.26

Cao/Sio2

37

Source: TATA TISCON steel

Rate: Rs 43/kg

Quality check: unit weight per meter length (in lab at site) complying to IS 1786 (7850

kg/m3)

Bars available in diameter: 6,8,10,12,16,20 and 25mm.

Product packaging: TATA TISCON 500D rebar is supplied in fixed length of 12 meter.

Table 2.1.18 Comparison between ordinary Fe 500 and TISCON 500D

Chemical Unit IS:1786 Fe500 TATA TISCON 500D

Carbon % 0.300 max 0.250 max

Carbon % 0.420 max 0.400 max

Sulphar % 0.055 max 0.035 max

Phosphorus % 0.055 max 0.035 max

S and P % 0.105 max 0.070 max

Table 2.1.19 Mechanical properties of TISCON 500D and ordinary Fe 500

Mechanical properties Unit IS 1786 Fe 500 TATA TISCON 500D

Yield stress(YS) N/mm2 500min 540 min

Ultimate tensile

stress(UTS) N/mm2 545 min 600 min

UTS/YS Ratio 1.08 min 1.12 min

Elongation % 12 min 18 min

3. Shuttering related materials

(a) Peri Domino formwork

Material: Peri domino wall panels ( Metsawood ply and Steel frame)

Company: PERI

Rate: Rs 8000/m2

Panels available in sizes of 1m, 0.75m, 0.5m, & 0.25m

Characteristics:

o With concreting height of up to 2.5m, the system has been designed for the full

hydrostatic pressure.

o For larger heights, 60 kN/m2 fresh concrete pressure is allowed.

(b) Shutter oil

Product name: Reebol WB

Company: FOSROC construction solutions

Rate: Rs 78/lit

Properties:

38

o Formwork surface: Reebol WB is compatible with timber, steel, GRP and resinous

formwork surfaces.

o Non-staining: Does not stain concrete, safely use with white cement.

o Steam curing: Reebol WB is effective at elevated temperature and can be used for steam

curing at 750 C.

Table 2.1.20 Mould oil properties

Colour White

Specific gravity 0.995 (at 200 C)

Viscosity 10 secs (at 200 C)

(c) Ply-board (12mm thick)

Company: Sharp-ply enterprise

Rate: Rs 590/m2

Properties: Concrete form plywood is a plywood with a plastic or phenolic impregnated

paper overlay to give excellent off form finishes and multiple re-uses.

(d) Cover blocks (PVC)

Sizes: 25mm, 50mm, 75mm.

Rate: 70 paise/block, Rs 1.5/block, Rs 2.2/block respectively.

Source: Bangalore (local dealer)

Ordered as per requirement, approx. 2000 pieces at a time.

(e) Binding wires

Source: TATA stock yard

Price: Rs 55/kg

(f) Hessian cloth for curing

Source: SPEC Hardware Shopyard

Rate: Rs 10/m

4. Material for anti-termite treatment and construction joint

(a) Anti-termite chemical

Chemical: BIFLEX-TC

Price: Rs 500/lit

Proportion with water: 1 part of chemical with 49 part water

Coverage: 3 litres/m2

Properties:

o It is a synthetic pyrethroid modelled on mother-natures very effective insecticide

pyrethrum which is extracted from the pyrethrum daisy.

o It has greater soil stability because it is less affected by soil factors such as soil pH, UV

light and soil moisture.

39

o Protection period is longer than other anti-termite chemicals like Chlorpyriphos and

Limidacloprid and it is around 12 to 13 years.

(b) Chemical for construction joint

Chemical: Nitobond EP Hardner

Company: FOSROC constructive solutions

Rate: Rs 1300/ lit

Coverage: 2.5 m2/liters

Properties:

o It has two component solvent-free epoxy resin.

o The two components shall be differently pigmented in order to ensure visually the

correct mixing has taken place prior to application.

o Two components are base and hardener which mixing thoroughly for at least 3

minutes until a uniform colour is obtained.

o Pot life for chemical is 35 to 45 minutes

o The base component is white and the hardener component is green, providing visual

evidence that adequate mixing has been achieved.

o The product shall achieve 70 N/mm2 compressive strength, 36 N/mm2 bond strength

and water absorption of 0.05% when tested in accordance to ASTM C881.

o Initial hardness is achieved in 24 hours.

o Full curing of 7 days is required.

o Minimum application temperature is 5o C.

o In general bond will always exceed the tensile strength of the concrete.

2.2.3 TOOLS, PLANTS & EQUIPMENT USED 1. Equipment

(a) For surveying

Total station: PENTAX COMPANY, Model-R205 XE

Auto level: SOKKIA B40

(b) For surface preparation

Soil compactor

(c) For reinforcement

Bar bending machine: SPARTAN SBM 42-S (2 Nos.)

Bar cutting machine: SCM 42

(d) For concreting

Transit mixer: SCHWING STETTER

Needle vibrator: WACKER NEUSON (60mm needle diameter)

Spraying equipment for anti-termite treatment.

40

Portable concrete pump: SCHWING BP 1800

Table 2.1.21 Portable concrete pump specifications

Description Units BP 1800 (Model name)

Engine/motor capacity kW 74

Pumping cylinder mm 2001600

Max. no. of strokes Per minute 24

Max. theoretical output M3/hour 73

Max. concrete pressure BAR 108

Dead weight Kg 4000

2. Plant

(a) Batching plant

Model: CP30

Company: SCHWING STETTER

3. Tools

Plumb bob

Straight edge aluminium beam for finishing (Screed)

Shovel

Line-dori

Hooked rod for binding wires (Aakdi)

Hammer

Measure tape

2.2.4 ENABLING WORKS

Construction of ramp

Availability of lighting mast & lighting facility for concreting at night

Housekeeping arrangement

2.2.5 CONCRETE POUR CARD (FOR RAFT OF TOWER-21) Table 2.1.22 Concrete Pour card (RAFT)

Sr no Date 6/2/14

1 Grade of concrete M30

2 Quantity of concrete 472 m3

3 Location Tower: 21 Raft

4 Are shuttering, reinforcement and

services completed Yes

5 Starting time 5 pm

6 Completion time 1 pm (7/2/14)

7 Number of cubes taken for testing 6

41

8 Slump value 120mm

2.2.6 CONSTRUCTION PROCEDURE

Construction activity is construction of raft of tower no. 21

Construction of raft include levelling of excavated surface, surveying of raft boundaries,

plain cement concrete, placing of reinforcement, shuttering and concreting.

However, excavation procedure was not in the scope of SPCL, it was done by the other

contractor from client side.

Construction procedure for above listed activities is as follow,

1. Setting out

There were two instruments used for the surveying work,

1] Auto level: For levelling purpose.

2] Total station: For setting out corner points and other necessary points.

Now, first when excavation is done, surveyor set-out corner point of boundary by

following procedure,

Two RL points on construction site is already established and their co-ordinates are

known.

Now instrument station is established and we can find the co-ordinates of instrument

station by re-section method, using two given RL points.

Now, on-paper co-ordinates of all points of boundary of raft is already inserted in the

instrument (Total station).

So, for setting any point on the boundary of raft, surveyor select point in total-station,

rotate it in horizontal plane and check the difference b/w inserted co-ordinates &

actual co-ordinates.

When this difference become (0,0), the point is set on boundary.

Than if any error in horizontal distance, than surveyor give order to the person which

was on point with prismatic rod to move on horizontal line until difference of

horizontal distance became zero or 1mm.

Than other corner points also set-out by this same re-section method.

Now, once boundary points were established, they insert rod (reinforcement of small

height) at all corner points.

Then levelling of the surface is done by the following procedure,

1] Levelling was done using auto-level and considering level of adjacent podium as

reference level

2] Adjacent podium taken as reference was podium between tower 35 & tower 21.

3] So once excavation is done up to nearly depth of 850mm (750mm raft thickness

100mm PCC), levelling is done by soil compactor to nearly attain the levelled

surface.

4] Then this levelled surface is checked by auto level at every 1m distance on both

side and on random points in between the raft area.

42

5] This bottom level must be (93m-0.85m) =92.15m, where 93m=Reference level of

top surface of adjacent podium and, 92.15m is level of bottom excavated levelled

surface.

6] So, if level of 92.15m is achieved at every selected points than levelling is

completed, otherwise same procedure is repeated again.

7] Level of the top surface of the raft is also 93m.

8] Levelling of the lift pit of trapezoidal shape is also done in same manner by

inserting rods at 4 upper points and 4 bottom points of pit and connecting them by

line-dory and then levelling the surface in parallel sloppy planes.


Anti-termite treatment is done after surface is levelled & before PCC is done.

Anti-termite material used is BIFLEX-TC and proportion with water is 1(chemical):

49(water).

This mixture is sprayed on surface by spraying machine at a rate of 3litre/m2.

Rate prescribed in IS code is 5litre/m2.

Once anti-termite is done, care should be taken to not disturb the surface.

3. PCC laying

Once levelled surface is attained in raft and lift pit, PCC work is done.

Grade of PCC used was M7.5 with proportion,

[1 (cement): 4 (FA): 8 (CA): 0.9 (water)]

Form work at boundary of raft is done by using channel section of ISMC-100 having

depth of 100mm which is equal to the thickness of PCC.

Also mark of 100mmis done on the rods inserted at corner points of raft and also at every

1m distance on both sides of raft.

PCC work is done by 15 no of labours, (3 masons and 12 unskilled labours) in the time of

24 hours.

Volume of PCC as per requirement is ordered from batching plant and transported to site

location by transit mixer having capacity of 8m3 but used only 6m3.

Levelling of PCC is done by levelling straight edge aluminium beam.

PCC of lift pit take 8 hours from whole duration.

Then this levelled PCC surface is checked by auto level and if undulations are there then

need to be corrected.

Then final level check is done from client side, and if levelling is done satisfactorily than

activity is approved.

Once PCC is done and surface is hardened, setting out of shear-wall edge points is done

by total station by same method of re-section by following same procedure stated earlier.

43

Figure 2.1.1 PCC laying arrangement for Lift pit's slopy surface

4. Reinforcement fabrication and placing

Once PCC is done and activity is approved by the client & PCC is hardened enough,

reinforcement placing is started.

Reinforcement for the raft is cut and bend in shape in steel yard and transported to the site

by trolley attached with tractor.

Marking is done on raft for laying reinforcement.

Once marking is done, bottom mesh is laid first.

Once bottom mesh is fixed in place, chairs are fixed on bottom mesh at approximate

distance of 1.5m to 1.2m.

Than top mesh is placed and fixed on chairs.

Points of shear-wall is already given by total station, so after deducting 25mm cover from

all sides, shear-wall reinforcement are placed in position.

Lift pit reinforcement are laid after bottom mesh is fixed and then top mesh is laid.

Extra bottom and extra top reinforcement are also laid as per drawing.

Development length (Ld) is given at every in-between termination of bars due to length

limitation.

Shear-key is provided at edge where raft is in-continuation with grade slab.

Also reinforcement of top mesh of raft is extended up to Ld length to maintain continuity

with grade-slab reinforcement.

Once all reinforcement are placed, reinforcement is checked by engineer from client side.

5. Shuttering

Once reinforcement laying is done and check by the client side, than after that, formwork

is done prior to concreting.

44

Formwork is done in adjacent two sides of raft where construction of grade slab was not

done.

Formwork is also done in lift pit.

This faces of raft where formwork is done is shown in drawing of formwork with detailed

sections of formwork.

Material used for formwork was

Peri-domino wall panels at boundary of raft.

Ply-formwork with stiffeners in lift pit and on boundary of raft.

ISMC 100 channel sections & hollow square sections at raft boundary.

Formwork is done by 12 labours in time duration of 8 hours.

Formwork is supported by inclined props from outside in lift pit and horizontal and

vertical props from inside also. (Shown in formwork drawing).

Formwork at periphery is also supported by inclined props from outside.

Oiling is done prior to fixing the formwork in PERI-DOMINO and in ply formwork.

6. RCC (M30 grade) laying

Once formwork is done and surface is cleaned from boulders & debris, than water is

sprayed on surface prior to concreting to wetting the surface.

Than once client approve the work and allow for concreting work than concreting is done.

Concreting is done by portable concrete pump.

Volume of concrete required is ordered from batching plant in transit mixture.

15 labours are there for concreting work, out of which 4 are mesons & 11 are unskilled

labours.

Compaction is done by immersion vibrators.

Time taken to complete concreting activity is 20 hours.

Pipe laid for concreting is shown in drawing.

Finishing of the surface is done by finishing aluminium beam.

Total quantity of concrete consumed in raft of tower no 21 is 470.9 m3.

Concreting is done in two-layer of equal depth & concreting is done in night time.

Slump obtained in laboratory for concrete is nearly about 120mm.

Once concreting is done, curing is done after 8-10 hours of concreting and curing is done

by ponding method.

2.2.7 MANPOWER EMPLOYED, PRODUCTIVITY AND COST

ASPECT

1. Plain cement concrete (PCC)

(a) Manpower employed:

15 labours out of which 3 were skilled and 12 were unskilled.

45

Time taken for activity: 24 hours out of which 8 hours were taken to complete lift pit PCC

due to slope surface and rest of duration in PCC of plain surface.

Theoretical consumption of PCC: It was calculated by plan dimension of raft and thickness

of PCC layer which was 100mm.

o Theoretical volume= 55.74m3 (plan rectangle) + 10.26m3 (side slope) + 6.725 m3 (lift

slope) 3.724m3 (lift plain surface) + 6.6m3 (outer projection)

o Theoretical volume=75.601 m3

Actual consumption on site for PCC of raft was 49m3.

(b) Productivity

Estimated productivity= 0.3125 m3/labour/hour (Estimation of productivity is assumed to

be same for skilled and unskilled labours since it is calculated considering them together).

Actual productivity = volume consumed actually/ (No. of labours hours).

=49m3/ (2415)

=0.136 m3/labour/hour

(c) Cost aspect

Per m3 cost of material for PCC is as follow,

o Total 13.9 kg=0.00567 m3

? = 1 m3

Hence, 2452.58 kg PCC/m3

Proportion for PCC is [1 (cement) : 4 (sand) : 8 (aggregates) : 0.9 (water)]

o Cement in kg/m3=176.44 kg/ m3

o FA in kg/ m3=705.77 kg/ m3

o CA in kg/ m3=1411.55 kg/ m3

Hence, per m3 cost = 176.445.2 + 0.67705.77 + 0.61411.55

= Rs 2237.28 / m3

Wages given to labour is Rs 250 for mason & 200 for unskilled labour.

So, per m3 labour cost=Rs 9450 for 49 m3

? for 1 m3

= Rs 192.86/ m3

Total cost incurred per m3 = Rs 2237.28 + 192.86

= Rs 2430.14 / m3

Now, rate as per BOQ = Rs 4224 / m3

Hence, (profit +overheads) / m3=Rs 1793.86/ m3

2. Form work

(a) Manpower employed

No of labours for shuttering=12

Time taken for shuttering =8 hours

Area covered

o Area for C=4.691 m2

o Area for SC=1.119 m2

46

o Area for CS=0.941 m2

o Area for 2C=0.92 m2

o Area for PD=4.675 m2

o Area for P= 8.46 m2

o Area for lift shuttering= 37.4 m2

o Total area = 58.286 m2

Where C, SC, CS, 2C, PD & P notations are given in drawing of formwork layout.

(b) Productivity

Estimated productivity=0.375 m2/labour/hour

Actual productivity= Area covered/ (no of labour time taken)

= 58.286 / (12 m2 8)

= 0.607 m3/labour/hour

(c) Cost aspect

Cost for Peri domino wall panel=Rs 8000/ m2

o No of repetitions (approx.) = 200 times

So, cost for one time = Rs 40 / m2

Cost for ply-wood formwork=Rs 590/ m2

o No of repetitions (approx.) = 30 times

So, cost for one time= Rs 19.67/ m2

Total material cost per m2=Rs 59.67 / m2

Total labour cost per m2= Rs 120 / m2

So, total shuttering cost= Rs 179.67 / m2

Rate quoted as per BOQ= Rs 475 / m2

Hence, (profit +overheads) / m2=Rs 295.33 / m2 (164.37%)

3. Reinforcement laying


No of labours for reinforcement laying=18

Time taken for reinforcement laying=5 days (12 hours in one day)

(b) Productivity

Estimated productivity= 18.75 kg/labour/hour

Actual productivity=(Total weight of reinforcement)/(No of labours time)

= 21226 kg / (18 60)= 19.65 kg/ labour hour

Where, 21226 kg= quantity of reinforcement in raft calculated in BBS= 4888 kg (shear

wall reinf.) + 16338 kg (raft reinf.)

(c) Cost aspect

Material cost = Rs 43 / kg

Labour cost= Rs 3.5 / kg

Total cost= Rs 46.5 / kg

47

Rate quoted in BOQ= Rs 60.645 / kg

Hence, (profit +overheads) / kg= Rs 14.145 / kg (30.41%)

4. Concrete work


No. of labour for concrete work=14 (4 masons + 10 labours)

Time taken for concrete work= 20 hours

1 supervisor and 1 site engineer was on site during the time of concreting.

(b) Productivity

Productivity of concrete work estimated is based on productivity of concrete pump.

Estimated productivity= 30 m3/hour

Actual productivity = Total volume of concreting actually consume/ time

= 478.95 m3/ 20 hours=23.947 m3/hour

(c) Cost aspect

Volume of concreting estimated as per plan dimensions and thickness of raft which was

750 mm is as below,

o Total volume of concreting

=418.07 m3 (volume of whole rectangle) + 9.4 m3 (volume of slope corner) + 31.54 m3

(volume of lift pit) 6.67 m3(Volume of hollow lift gap)

=470.95 m3

Proportion of mix design for concrete was:

[1(cement):1.787(FA):2.324(CA):0.3255(water):0.321(GGBS)]

Material in one m3

o Cement=265 kg/ m3

o GGBS=85 kg/ m3

o FA= 826 kg/ m3

o CA=1074.5 kg/ m3

o Water=150.5 kg/ m3

o Admixture=1.575 litres

Cost of material per m3= 2655.2 + 853.128 + 8260.67 + 644.70.6 +429.80.53 +

1.57554 = Rs 2896.96 / m3

Labour cost / m3=Rs 15.65

Total cost incurred=Rs 2912.61/ m3

Rate quoted in BOQ=Rs 5456/ m3

Hence, (profit +overheads) in Rs / m3=2543.12/ m3 (87.31%)


Material used=BIFLEX TC

Coverage=3 litres/ m2

Proportion is 1 time chemical with 49 times water

48

o So, in 3 litres, quantity of chemical= 0.06 litres

o And, spray of chemical per m2=0.06 litres

Now, cost of chemical per m2=Rs 30

Rate quoted in BOQ per m2=Rs 52

Hence, (profit+overheads) per m2=Rs 22 (73.33%)

Table 2.1.23 TOTAL COST FOR RAFT

Sr. no Activity Price as per BOQ(Rs) Cost incurred (Rs) Profit

overheads(Rs)

1 PCC 4224 75.6=3,19,3334 2430.1449=1,19,077 2,00,257.4

2 Formwork 47558.936=28,007.43 141.5550.535=7153 20,854.43

3 Reinforcement 60.64521226=12,84,250 46.521226=9,87,009 3,00,241

4 Concrete

works-M30 5456474.7=25,89,963 2912.61478.95=13,94,994 11,35,998

5 Anti-termite

treatment 53554.43=29,543 30557.43=16,772 12821

6 Total 42,54,097.43 25,25,005 17, 29,092.43

(68.48%)

Formwork area(considered by client) = 0.3m depth (38.31m + 33.565m)

= 21.563 m2 (non-lift area)

o Lift area = (8.5m 2) (2.2m height)= 37.4 m2

o Total area= 58.936 m2

2.2.8 INSPECTION AND QUALITY CHECKS Inspection and quality checks for any construction activity involves filling up of

CHECKLIST which covers following points.

1. Checks for surveying work for raft

Checking of co-ordinates of raft corners and shear walls corners by surveyor from client

side.

They check that the points located by SPCL surveyor is correct or not.

Tolerance of 1mm in horizontal direction is allowed.

2. Checklist for reinforcement

Checklist for form work.

Test conducted on received material & report.

Structural drawing checked & last revision being used.

Bar bending schedule prepared & bar bending and cutting is done satisfactorily.

Bar sizes, spacing, grades, shapes & lengths as per drawing.

Adequate laps

49

Chairs/cover blocks placed

Binding wire not touching shuttering and proper binding

Dowels & positioning as per drawings.

Joggling is avoided and if it is to be done then it should not be more than 1 in 6.

3. Checklist for shuttering

Are all the safety norms being covered as per HSEM (health & safety executive minute)

process?

Check for shuttering for availability and arrangement.

Are all plates and ply-woods cleaned and polished properly.

Type of oil/polish used on the surface of shuttering.

Check for suitability, stability, safety and rigidity of assembled forms

Check for provisions for service piping.

Vertical member-Shear walls

Checking alignment of all vertical members at floor level with respect to grid lines.

Check plumb for vertical members (minimum 2 sides).

Check right angles and diagonals of the vertical members from the top.

Check for alignment with respect to adjacent vertical members.

Check for adequate support as per shuttering design.

Check for adequacy of cover blocks.

4. Checklist prior to concreting

All the safety norms being covered as per HSEM process?

Check whether the concrete is as per approved mix design.

Check for formwork, reinforcement and cleanliness of the area to be concreted, is it OK?

Check for completion of preceding activities such as fixing of inserts and embedment.

Check for completion of preceding activities such as fixing of services conduits, electrical

conduits etc.

Check whether the location of expansion joints are as per drawings?

Is the sequence of concreting decided and explained to all concerned?

Check for readiness of electrical equipment during concreting.

Are protective covers against rain provided?

Check whether sufficient material and manpower are available?

Check the availability of sufficient no. of cube modules, slumps quality apparatus?

Are the reference levels transferred from TBM marked?

Mode of concreting proposed (mixer machine, Batching plant)

Grade of concrete

Total quantity of concrete

Date & time of concreting

50

5. Checking during concreting

Check for slump.

Check for temperature of concrete in case of temperature controlled concrete.

Check for placing methodology of concrete. Is it OK?

Is concrete being consumed within the initial setting period of concrete?

Check for provision of construction joints as per drawings?

Check for levelling and finishing of exposed concrete surface for planner structures like

slabs/rafts & pavements.

6. Check list after concreting

Check for suitable curing arrangements.

Check for casting date is marked on the structural element.

Check whether inserts which are embedded with concrete surface are exposed properly.

Check for alignment of construction joints, if any.

Is the line/level of concrete surface is OK?

Check for defects on exposed concrete

o Honey combing

o Dimension variance

o Bulging

o Exposed reinforcement

o Damaged edges and corners

raft foundation f

Documents

cement bags

mt of cement

cement test

coarse aggregates

conformity of cement

brand of cement

source of aggregates

b aggregates fine aggregates