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TECHNICAL SPECIFICATIONS- CIVIL

1. The following Technical specification, code of practice etc. referred herein is form a part of the Item
Specification and work shall be executed accordingly. Items which are not covered under Technical
specification shall be carried out as per relevant IS Specification or as per manufactures specification
or as directed by the Engineer- in- charge.

2. In case of discrepancy between technical specification and item specification provided along with
Bill of Quantities, the Item Specification shall prevail.

3. All the measurements shall be as per latest edition of B.I.S.

1.0 EARTH WORK

1.1 Applicable Codes

The following Indian Standard Codes, unless otherwise specified herein, shall be applicable. In all
cases, the latest revision of the codes shall be referred to.

a) IS – 4081 Safety code for blasting and other related drilling operation.
b) IS – 1200 Method of measurement of building works.
c) IS – 3764 Safety code for excavation work.
d) IS – 3385 Code of practice for measurement of civil Engineering works.
e) IS – 2720 Part II Determination of moisture content

Part VIII Determination of moisture content dry density relation using light compaction.

Part XXVIII Determination of dry density of soils, in-place by the sand replacement method.

Part XXIX Determination of dry density of soils, in-place by the core cutter method.

1.2 General

1.2.1 Contractor shall carry out the survey of the site before excavation and set properly all lines and
establish levels for various works such as earthwork in excavation for leveling, basement,
foundations, plinth fillings, roads, drains, cable trenches, pipelines. Etc. It is necessary to establish
permanent bench mark at such point which will not be affected by subsequent work. Such survey
shall be carried out by taking accurate cross sections of the perpendicular to the established
reference/grid lines at 5 m intervals or nearer as determined by the Engineer – in – charge based on
ground profile.

1.2.2 The area to be excavated/filled shall be cleared of fences, trees, plants, slumps, bush, vegetations,
rubbish slush, etc., and other objectionable matter. If any roots or stumps of trees are found during
excavation, they shall also be removed. The material so removed shall be burnt or disposed off as
directed by the Engineer. Where earth fill is intended, the area shall be stripped of all loose / soft
patches, top soil containing deleterious matter/materials before fill commences.

1.2.3 In firm soil if the excavation is deeper than 2 m and in loose, soft or slushy soil, the width of the step
shall be suitably increased or the sides slopped or shoring or strutting may be done as per the
Engineer’s instructions without any extra cost

1.2.4 For excavation in trenches for pipes nothing extra shall be payable for the lift irrespective of the
depth unless specifically mentioned otherwise in the Schedule of Quantities.

1.2.5 The trenches which are ready for concreting shall be got approved by the Engineer.
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1.2.6 The excavated stacked earth shall be refilled in the trenches and sides of foundation in 200 mm
layers and the balance surplus shall be first filled in layers in plinth and the remaining surplus shall
be disposed off by uniform spreading within the site/outside the site as directed by the Engineer.

1.2.7 Adequate protective measures shall be taken by the contractor to see that the excavation for the
building foundation does not affect the adjoining structure’s stability and safety. Contractor will be
responsible if he has not taken precaution for the safety of the people, worker’s property or
neighbor’s property caused by the negligence during the constructional operations.

1.2.8 Lead

Lead for disposal of excavated material inside the site and at convenient places in the surrounding
areas have been specified in the respective items of work and no other extra lead is intended.

1.3 Classification

Any earthwork will be classified under any of the following categories.

1.3.1 All kinds of soils

These shall include all kinds containing kankar, sand, silt, moorum and/or shingle, gravel, clay, loam
peat, ash, shale etc., which can generally be excavated by spade, pick-axe and shovel and which is
not classified under ordinary rock, and hard rock defined below. This shall also include excavation
in macadam and tarred roads and pavements. This shall also include rock boulders up to 200
dm3.Rubble masonry to be dismantled below ground level will also be measured under this item.

1.3.2 Ordinary Rock

These shall include generally any rock which can be excavated by splitting with crow bars or picks
and does not require blasting, wedging or similar means for excavation such as lime stone, sand
stone, hard laterite, hard conglomerate and unreinforced cement concrete below ground level.

1.3.3 Hard Rock

This shall include rock which cannot be easily excavated by pick-axes, hammer, crow bars and
wedges but has to be either heated where blasting is prohibited or has to be blasted. They shall be
staked separately for measurement as directed by the Engineer – in – charge.

1.4 Blasting in rocks

1.4.1 Unless otherwise stated herein, IS 4058, safety code for blasting and related drilling operations shall
be followed. After removal of over burden, if any, excavation shall be continued in rock to such
widths, lengths, depths and profiles as are shown on the drawings or such other lines and grades as
may be specified by Engineer. As far as possible all blasting shall be completed prior to
commencement of construction. At all stages of excavation, precautions, shall be taken to preserve
the rock below and beyond the lines specified for the excavating, in the soundest possible condition.
The quantity and strength of explosive used shall be such as will neither damage nor crack the rock
outside the limits of excavation. All precautions as directed by the Engineer shall be taken during the
blasting operations and care shall be taken that no damage is caused to adjoining buildings or
structure as a result of blasting operations. In case of damage to permanent or temporary structures,
Contractor shall repair the same to the satisfaction of the Engineer at his cost. As excavation
approaches its final lines and levels, the depth of the charge holes and amount of explosives used
shall be progressively and suitably reduced.

1.4.2 Specific permission of the Engineer will have to be taken by Contractor for blasting rock and he
shall also obtain a valid blasting license from the authorities concerned. If permission for blasting is
refused by the Engineer, the rock shall be removed by wedging, pick barring, heating and quenching
or other approved means. All loose/loosened rock in the sides shall be removed by barring, wedging,
etc. The unit rates for excavation in hard rock shall include the cost of all these operations.

1.4.2.1 Contractor shall employ a competent and experienced supervisor and licensed blaster in charge for
each set of operation, who shall be held personally responsible to ensure that all safety regulations
are carried out.
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1.4.2.2 Before any blasting is carried out, Contactor shall intimate Engineer – in – Charge and obtain his
approval in writing for resorting to such operations. He shall intimate the hours of firing charges, the
nature of explosive to be used and the precautions for ensuring safety.

1.5.1 Plinth shall be filled in layers 15-30 cm, of thickness or as specified in items specification watered
and compacted with hand rammers as directed by the Engineer – in – charge, so as to avoid any
settlement at later stage. For the final layer the surface shall be flooded with water and water allowed
to stand for 24 hours. The finished level of filling shall be trimmed to the level specified.

1.5.2 Where specified in the item description given in the schedule of Quantities that the compaction of
the plinth fill shall be carried out by means of 10/12 tonnes rollers smooth wheeled, sheep foot or
wobble wheeled rollers. As rolling proceeds water sprinkling shall be done to assist consolidation.
Water shall not be sprinkled in case of sandy fill.

1.6 Filling excavated earth in ground for land development

1.6.1 No earth fill shall commence until surface water discharges and streams have been properly
intercepted or otherwise dealt with as directed by Engineer - in charge.

1.6.2 Filling shall be carried out as indicated in the drawings and as directed by the Engineer - in charge.
If no compaction is called for, the fill may be deposited to the full height in one operation and
leveled. If the fill has to be compacted, it shall be placed in layers not exceeding 600 mm and leveled
uniformly and compacted before the next layer is deposited.

1.6.3 Field compaction is called for; test shall be carried out at different stages of filling and also after the
fill to the entire height has been completed. This shall hold good for embankments as well. The tests
for field compaction shall be specified by the Engineer - in charge and the contractor shall arrange to
carry out such tests to the satisfaction of the Engineer - in charge.

1.6.4 Contractor shall protect the earth fill from being washed away by rain or damaged in any other way.
Should any slip occur, contractor shall remove the affected material and make good the slip at his
own cost.

1.6.5 The fill shall be carried out to such dimension and levels as indicated on the drawings after the
stipulated compaction. The fill shall be considered as incomplete if the desired compaction has not
been obtained.

1.6.6 Filling in plinth and ground with earth brought from outside

1.7.1 Filling shall be carried out with approved material. The material and source shall be subject to prior
approval of Engineer -in- charge. The approved area, from where the fill material is to be dug, shall
be cleared of all bushes, roots plants, rubbish, etc., top soil containing salts, sulphate and other
foreign material shall be removed. The materials so removed shall be burnt or disposed off as
directed by Engineer- in-charge. The contractor shall make necessary access roads to those areas and
maintain the same, if such access road does not exist, at his cost.

1.7.2 If any material is rejected by the Engineer in charge, Contractor shall remove the same forthwith
from the site at no extra cost to the owner. Surplus fill material shall be disposed off by uniform
spreading within the site as instructed by the Engineer in charge.

1.7.3 At places backfilling shall be carried out with local sand if directed by Engineer. The sand used shall
be kept flooded with water for 24 hours to ensure maximum consolidation. Any temporary work
required to contain sand under flooded condition shall be to contractor’s account. The surface of the
consolidated sand shall be dressed to required level or slope. Construction of floors or other
structures on sand fill shall not be started until Engineer has inspected and approved the fill.

1.7.4 Bored Cast-in-situ Pile Foundation

1.8.1 The tenderer has to acquaint himself with the site condition before tendering the work.
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1.8.2 The contractor shall be responsible for the correctness of location of pile points as given with the
pile layout drawing which will be supplied to the contractor. If any lateral shift or tilt of the pile is
noticed, the contractor will have to drive alternate pile at his own cost as directed by the Engineer—
in- charge whose decision shall be final. Any excess quantity of RCC pile cap if necessitated due to
driving such alternate pile will have to be done by the contractor, at his own cost.

1.8.3 Piles have t be socketed in hard rock by 500 mm.

1.8.4 The length of pile for payment shall be from bottom of pile cap to the bottom tip of pile.

1.8.5 Concreting of pile shall be done upto ground level and later chipped off upto cut-off level by the
contractor. Charges for these shall be deemed to have been included in the rate quoted for piling.

1.8.6 Main steel of piles shall be kept projecting from the top to the extent of 50 times the diameter of the
bar for use as dowels in pile cap/grade beam.

1.8.7 Cement and steel to be used on the work shall conform to prevailing IS Standards.

1.8.8 Any ground with high water table or in soft soil having unstable pile bores, boring and under ream
may be carried out with suitable drilling works.

1.8.9 The bentonite suspension used in boreholes is basically a clay of montmorillonite group having
exchangeable sodium cations.

1.8.9.1 The bentonite suspension used for piling work shall satisfy the following requirements:

1.8.9.2 The Liquid limit of bentonite when tested in accordance with IS 2720(part V) 1965 shall be more
than 300 percent and less than 450 percent.

1.8.9.3 The sand content of the bentonite powder shall not be greater than 7 percent.

1.8.9.4 Bentonite solution should be made by mixing it with fresh water using pump for circulation
The relative density of the bentonite solution should be about 1.12.

1.8.10 Concreting shall be done as soon as possible after completing the pile bore. The bore hole full of
drilling mud should not be left unconcreted for more than 12 to 24 hours depending upon the
stability of the bore hole.

1.8.11 For placing concrete in bore holes, a funnel should be used and method of concreting should be such
that the entire volume of the pile bore is filled up without the formation of voids and/or mixing of
soil and drilling fluid in the concrete.

1.8.12 In empty bore holes for piles a small quantity of concrete is poured to give about a 100 mm layer of
concrete at the bottom. Reinforcement is lowered next and positioned correctly. Then concrete is
poured to fill up the bore hole. Care should be taken that soil is not scrapped from sides if rodding is
done for compaction. Vibrators shall not be used.

1.8.13 In case the pile bore is stabilized with drilling mud or by maintaining water head within the bore
hole, the bottom of bore hole shall be carefully cleaned by flushing it with fresh drilling mud, and
pile bore will be checked for its depth immediately before concreting.

1.8.14 Concreting shall be done by tremie method. The tremie should have a valve at its bottom and
lowered with its valve closed at the start and filled up with concrete. The valve is then opened to
permit the flow of concrete which permits the upward displacement of the drilling mud. The pouring
should be continuous and tremie is gradually lifted up such that the tremie pipe opening remains
always in the concrete. In the final stage the quantity of concrete in the tremie should be enough so
that on final withdrawal some concrete spills over the ground.

1.8.15 The work shall be done as per IS 2911 (Part I /Section II)1979 latest edition.
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2.0 CONCRETE AND ALLIED WORKS

2.1 Applicable codes

The following codes and standards are made a part of the specifications. All standards, codes of
practices referred to herein shall be the latest edition including all applicable official amendments
and revisions.

In case of discrepancy between this specification and those referred to herein, this specification shall
prevail.

2.1.1 Materials

1) IS 269: Specification for ordinary , rapid hardening and low heat Portland cement
2) IS 455: Specification for Portland blast furnace slag.
3) IS 1489: Specification for Portland – Pozzalana cement
4) IS 4031: Methods of physical tests for hydraulic cement
5) IS 650: Specification for standard sand for testing of cement
6) IS 383: Specification for course and fine aggregates from natural sources for concrete.
7) IS 2386(Parts I to VIII): Methods of test for aggregates for concrete.
8) IS 516: Methods of test for strength of concrete.
9) IS 1199: Methods of sampling and analysis of concrete.
10) IS 2396(I) IS 5640 : Flakiness Index of aggregates.
11) IS 3025: Methods of sampling and test(physical and chemical water used in industry).
12) IS 432(Part I &II): Specification for mild steel and medium tensile steel bars and hard
drawn steel wire for concrete reinforcement.
13) IS 1139: Specification for hot rolled mild steel and medium tensile steel deformed bars for
concrete reinforcement.
14) IS 1566: Specification for plain hard drawn steel wire fabric for concrete reinforcement.
15) IS 1785: Specification for plain hard drawn steel (Part I ) steel wire for prestressed
concrete.
16) IS 1786: Specifications for cold twisted steel bars for concrete reinforcement.
17) IS 2090: Specifications for high tensile steel bars used in prestressed concrete.
18) IS 4990: Specifications for plywood for concrete shuttering work.
19) IS 2645: Specifications for integral cement water-proofing compounds.

2.1.2 Equipment

1) IS 1791: Specification for batch type concrete mixers.

2) IS 2438: Specifications for roller pan mixer
3) IS 2505 : Specifications for concrete vibrators immersion type
4) IS 2506: Specifications for screed bored concrete vibrators.
5) IS 2514: Specifications for concrete vibrating tables.
6) IS 3366 : Specifications for pan vibrators
7) IS 4656: Specifications for form vibrators for concrete
8) IS 2722:Specification for portable swing weigh batchers for concrete(single and double bucket
type)
9) IS 2750: Specification for steel scaffoldings.

2.1.3 Codes of Practice

1) IS 456 : Code of practice for plain and reinforced concrete

2) IS 1343 : Code of practice for prestressed concrete
3) IS 457 : Code of practice for general construction of plain and reinforced concrete for dams and
other massive structures
4) IS 3371(Part I to IV): Code of practice for concrete structures for storage of liquids.
5) IS 3935: Code of practice for composite construction
6) IS 3201: criteria for design and construction of precast concrete trusses
7) IS 2204: Code of practice for construction of concrete shell roof.
8) IS 2210 : Criteria for the design of RC shell structures and folded plates.
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9) IS 2751 : Code of practice for welding of mild steel bars used for reinforced concrete
construction
10) IS 2502: Code of practice for bending and fixing of bars for concrete reinforcement
11) IS 3558: Code of practice for use of immersion vibrators for consolidating concrete.
12) IS 3414: Code of practice for design and installation of joints in buildings
13) IS 4014(Part I & II): Code of practice for steel tubular, Scaffolding
14) IS 2571 : Code of practice for laying in situ cement concrete flooring

2.1.4 Construction Safety

1) IS 3696 : Safety code for scaffolds and ladders.

2.1.5 Measurement

1) IS 1200 : Method of measurement of building works.

2) IS 3385 : Code of practice for measurement of civil Engineering works

2.2 General

The quality of materials ,method and control of manufacture and transportation of all concrete work
irrespective of mix, whether reinforced or otherwise shall conform to the applicable portions of this
specification.

2.3.1 Cement

2.3.1.1 If the contractor is instructed to supply cement, then the following points shall be applicable:

a) The cement to be used shall be ordinary Portland cement conforming to IS 8112-1989

for 43 grade OPC unless other wise mentioned. The cement procured should be of
reputed brands such as Malabar cements, ACC, L&T, Shankar cement, etc. and as
approved by the Engineer in charge. As far as possible, all the cement shall be obtained
from a single source throughout the contract. Cement of different types shall not be
mixed together. Different brands of cements or same brand of cements from different
sources shall not be used without the prior approval of the Engineer in charge.

The cement shall be delivered at site in original sealed bags which shall be labeled with
the weight, date of manufacture, brand and type. Cement received in ton or hand
stitched bags shall not be used. For volumetric batching of concrete cement should be
mixed only by box measurement All cement should be fresh when delivered and shall
be stored in an approved manner in stores built by the contractor at his own cost. Set
cement shall not be allowed to be used for any work.

b) A certified report attesting to the conformance of the cement to IS specifications by the

cement manufacturer’s chemist shall be furnished to engineer if demanded.

c) Cement held in storage for a period of sixty (60) days or longer shall be tested. Should
at any time Engineer have reasons to consider that any cement is defective, then
irrespective of its origin, and/or manufacturers test certificate, such cement shall be
tested immediately at contractor’s cost at an approved laboratory and until the results
of such tests are found satisfactory, it shall not be used in any work. Contractor shall
not be entitled to claim of any nature on this account.

d) Contractor will have to make his own arrangements for storage of adequate quantity of
cement.

e) The site Engineer shall be regularly notified when supplies of cement are made to the
site store. Copies of invoices shall be made available to the site engineer and a
common cement register shall be kept at his office showing the supply stock and issue
on a daily basis.
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2.3.1.2 If the cement is supplied by the client

a) Contractor will have to make his own arrangements for the storage of cement. If
supplies are arranged by owner, cement will be issued in quantities to cover work
requirements of one month or more, as deemed fit by Engineer and it will be the
responsibility of the contractor to ensure proper and adequate storage. The Storage
arrangements shall be such that there is no dead storage. The storage arrangement shall
be approved by Engineer.

2.3.2 Aggregates

2.3.2.1 Aggregate in general designates both fine and coarse inert materials used in the manufacture of
concrete. Fine aggregate is aggregate of all of which passes through 4.75 mm sieve. Coarse
aggregate is most of which is retained on 4.75 mm sieve. Specification mentioned against various
item of work may also be followed.

2.3.2.2 All fine and coarse aggregates proposed for use in the work shall be subject to Engineer’s approval
and after specific materials have been accepted the source of supply of such materials should not be
changed without prior approval of Engineer.

2.3.2.3 Aggregates shall, except as noted above, consist of natural sands, crushed stone and gravel from a
source known to produce satisfactory aggregate for concrete and shall be chemically inert, strong,
hard, durable against weathering, of limited porosity and free from deleterious materials that may
cause corrosion of the reinforcement or may impair the strength and/or durability of concrete. The
grading of aggregates shall be such as to produce a dense concrete of specified strength and
consistency that will work readily into position without segregation and shall be based on the mix
design and preliminary tests on concrete specified later.

2.3.2.4 Sampling and testing

Samples of the aggregates for mix design and determination of suitability shall be taken under the
supervision of the Engineer and delivered to the laboratory, well in advance of the scheduled placing
of concrete. Records of tests which have been made on proposed aggregates and on concrete made
from this source of aggregates shall be furnished to Engineer in advance of the work for use in
determining aggregate suitability. The costs of all such tests, sampling, etc., shall be borne by
contractor.

2.3.2.5 Storage of aggregates

All coarse and fine aggregates shall be stacked in stock separately in stock piles in the materials yard
near the work site or if instructed in bins properly constructed to avoid intermixing of different
aggregates. Contamination with foreign materials and with earth during storage and while heaping
the materials shall be avoided. The aggregate must be specified quality not only at the time of
receiving at site but more so at the time of loading into mixer.

2.3.2.6 Screening and washing

a) Sand shall be prepared for use for such screening or washing, or both, as necessary, to
remove all objectionable foreign matter while separating the sand grains to the required
size fractions.

b) Natural gravel and crushed rock shall be screened and/or washed for the removal of
dirt or dust coating, if so demanded by the Engineer.
2.3.3 Water

2.3.3.1 Water used for both mixing and curing shall be free from injurious amount of deleterious materials.
Potable waters are generally satisfactory for mixing and curing concrete.
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2.3.3.2 In case of doubt, the suitability of water for making concrete shall be ascertained by the compressive
strength and initial setting time test specified in IS 456.The sample of water taken for testing shall be
typical of the water proposed to be used for concreting, due account being paid to seasonal variation.
The Sample shall not receive any treatment before testing other than that envisaged in the regular
supply of water proposed form use in concrete. The sample shall be stored in a clean container
previously rinsed out with similar water
.
2.3.4 Brick Aggregates

The brick bats shall be of new bricks well burnt, hard, durable and broken into sizes, well graded. It
shall be free from dust; the size shall be of 37 mm and down. It shall be free from earth and other
impurities

2.3.5 Mix Design

2.4.1 Classification

2.4.1.1 In case of concrete works, mix design may be necessary as per IS : 456 for certain items as directed
by Engineer – in charge. All concrete in the works shall be of design mix as defined in IS 456,
unless it is a nominal mix concrete such as 1:3:6, 1:4:8, 1:5:10. Whether reinforced or otherwise, all
design mix concrete works to be carried out under this specification shall be divided into the
following classifications (refer clause 2.6.3 for testing of concrete)

MINIMUM COMPRESSIVE STRENGTH OF 15 CM CUBES AT 7 AND 28 DAYS AFTER

MIXING, CONDUCTED IN ACCORDANCE WITH IS 516

Class Preliminary N/SQ.MM Work test N/SQ.MM Max size of

At 7 days At 28 days At 7 days At 28 days aggregates
M30 28.0 42.0 20.0 33.0 40 or 20
M25 23.5 35.0 17.0 28.0 40 or 20
M20 19.4 29.0 13.5 22.0 40 or 20
M15 14 17.0 10.0 16.0 40 or 20

2.4.1.2 It shall be clearly understood that whenever the class of concrete such as M 20 is specified it shall be
the contractor’s responsibility to ensure that minimum crushing strength stipulated for the respective
class of concrete is obtained at works. The maximum total quantity of aggregate by weight per 50 kg
of cement shall not exceed 250 kg except when otherwise specifically permitted by engineer.

2.4.1.3 To fix the grading of aggregates, water cement ratio, workability and the quantity of cement required
to give preliminary and works cubes of the minimum strength specified, the proportions of the mix
shall be determined by weight. Adjustment of aggregate proportions due to moisture presenting the
aggregate shall be made. Mix proportioning shall be carried out according to Indian Standard
Specifications

2.4.1.4 Whenever there is a change either in required strength of concrete or water cement ratio or
workability or the source of aggregates and/or cement, preliminary tests shall be repeated to
determine the revised proportions, of the mix to suit the altered conditions.

2.4.1.5 While fixing the value for water cement ratio for preliminary mixes, assistance may be derived from
the graph(appendix IS 456) showing the relationship between the 28 day compressive strengths of
concrete mixes with different water cement ratios and the seven day s compressive strength of
cement tested in accordance with IS 269.

2.4.2 Preliminary tests

2.4.2.1 Test specimens shall be prepared with at least two different water cement ratios for each class of
concrete, consistent with workability required for the nature of the work. The materials and
proportions used in making preliminary tests shall be similar in all respects to those to be actually
employed in the works as the objects of these tests is to determine the proportions of cement,
aggregates and water necessary to produce concrete of required consistency and to give the
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specified strength. It will be the contractor’s sole responsibility to carry out these tests and he shall
therefore furnish to Engineer a statement of proportions proposed to be used for the various concrete
mixes.

2.4.2.2 Materials shall be brought to room temperature and all materials shall be in a dry condition. The
quantities of water, cement and aggregates for each mix shall be determined by weight/volume to an
accuracy of 1 part in 1000 parts.

2.4.2.3 Mixing shall be done by a mixer machine as per IS516 in such a manner as to avoid loss of water.
The cement and fine aggregates shall first be mixed dry until the mixture is uniform in colour. The
coarse aggregate shall then be added, mixed and water added and mixed thoroughly for a period of
not less than 3 minutes until the resulting concrete is uniform in appearance. Each mix of concrete
shall be of such a quantity as to leave about 10 % excess concrete after moulding the desired number
of test specimens.

2.4.2.4 The consistency of each mix of concrete shall be measured immediately after mixing, by then slump
test in accordance with IS 1199.If in the slump test, care is taken to ensure that no water or other
materials is lost, the materials used for slump test may be remixed with the remainder of the concrete
for making the specimen test cubes. The period of remixing shall be as short as possible yet
sufficient to produce am homogeneous mass.

2.4.2.5 Compression tests of concrete cubes shall be made as per IS 516 on 15 cm cubes. Each mould shall
be provided with a metal base having a plane surface so as to support the mould during filling
without leakage. The base plate shall be preferably attached to the mould by springs or screws. The
parts of the mould when assembled shall be positively and rigidly held together. Before placing
concrete the mould and base plate shall be cleaned and oiled. The dimensions and internal faces of
the mould shall be accurate within the following limits.

2.4.2.6 Height and distance between the opposite faces of the mould shall be of specified size plus or minus
0.2mm.The angle between the adjacent internal faces and between internal faces and top and bottom
planes of mould shall be 90 deg plus or minus 5 deg. The interior faces of the mould shall be plane
surfaces with a permissible variation 0.03mm.

2.4.2.7 Concrete test cubes shall be moulded by placing fresh concrete in the mould and compacted as
specified in IS 516.

2.4.2.8 Curing shall be as specified in IS 516.The cubes shall be kept in moist air of at least 90% relative
humidity at a temperature of 27 deg C +/- 2 deg C for 24 hours +/- half hour from the time of adding
water to the dry ingredients. Thereafter they shall be removed from the moulds and kept immersed in
clean, fresh water and kept at 27 deg C+/- 2 deg C temp. Until required for test. Curing water shall
be renewed every 7 days. A record of maximum and minimum temperatures at the place of storage
of the cubes shall be maintained during the period they remain in storage.

2.4.2.9 Testing of specimens

The strength shall be determined based on not less than five cubes test specimens for each age and
each water cement ratio. All these laboratory test results shall be tabulated and furnished to
Engineer. The test result shall be accepted by Engineer if the average compressive strengths of the
specimens are tested subject to the condition that only one out of the five consecutive tests may give
a value less than the specified strength for that age. The Engineer may direct the contractor to repeat
the tests if the results are not satisfactory and also to make such changes as he considers necessary to
meet the requirements specified. All these preliminary tests shall be conducted by the contractor at
his own cost in an approved laboratory.

2.4.3 Proportioning, consistency, batching and mixing of concrete

2.4.3.1 Aggregate

The proportions which shall be decided by conducting preliminary test shall be by volume. These
proportions of cement, fine and coarse aggregates shall be maintained during subsequent concrete
mixing. The supply of properly graded aggregate of uniform quality shall be maintained over the
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period of work, the grading of aggregates shall be controlled by obtaining the coarse aggregate in
different sizes and blending them in the right proportions. The different sizes shall be stocked in
separate stock piles. The grading of coarse and fine aggregates shall be checked as frequently as
possible as determined by the Engineer, to ensure maintaining of grading in accordance with the
samples used in the preliminary mix design. The materials shall be stock piled well in advance of
use.

2.4.3.2 Cement
The cement shall be measured by weight.

2.4.3.3 Water

Only such quantity of water shall be added to the cement and aggregates in the concrete mix as to
ensure dense concrete, specified surface finish, satisfactory workability, consistent with the strength
stipulated for each class of concrete. The water added to the mix shall be such as not to cause
segregation of material or the collection of excessive free water on the surface of concrete
The water cement ratio will be decided by the Engineer in charge on weight basis and this shall be
strictly followed at site.

2.4.3.4 Proportioning by water cement ratio

The water cement ratio specified for use by Engineer shall be maintained. The contractor shall
determine the water content of the aggregates as frequently as directed by the Engineer as the work
progress and as specified in IS 2386(part III) and the amount of water added to the mixer shall be
adjusted as directed by the Engineer so as to maintain the specified W/C ratio. To allow for the
variation in volume of aggregates due to variation in their moisture content suitable adjustments in
the volume of aggregates shall also be made.

2.4.3.5 Consistency and slump

Concrete shall be of a consistency and workability suitable for the conditions of the job. After the
amount of water required is determined, the consistency of the mix shall be maintained throughout
the progress of the corresponding parts of the work and approved tests e.g. Slump tests, compacting
factor tests, in accordance with IS 1199 shall be conducted from time to time to ensure the
maintenance of such consistency.

2.5 Slumps for various types of construction

Only sufficient quantity of water shall be added to concrete during the mixing to produce a mix of
sufficient workability to enable it to be well consolidated, to be worked into the corners of the
shuttering and around the reinforcement, to give the specified surface finish, and to have the
specified surface strength. The following slumps shall be adopted for different kinds of works:

Placing Conditions Degree of Workability Slump(mm)

(1) (2) (3)
Blinding Concrete
Shallow sections Very low
Pavements using pavers
Mass Concrete: Low 25-75
Lightly reinforced sections in slabs,
Beams, walls, columns
Floors
Hand placed pavements Medium
Canal Lining
Strip footings
Heavily reinforced sections in slabs, 50-100
Beams, walls, columns 75-100
Slip form work, Pumped concrete Trench High 100-150
fill
In-Situ piling Very high
Tremie concrete
 - 11 -

2.6 Sampling and testing concrete in the field

2.6.1 Facilities required for sampling materials and concrete in the field shall be provided by the
contractor at no extra cost. The following equipment with operator shall be made available at
Engineer’s request (all must be in serviceable condition):

a) One concrete cube testing machine suitable for 15 cm cubes of 100 tonnes capacity
with proving calibration ring.
b) Twelve cast iron cube moulds of 15 cm size
c) One Lab. balance to weigh upto 5 Kg with sensitivity of 10 gm.
d) One set of sieves for coarse and fine aggregates
e) One set of slump cone complete with tamping rod
f) A set of measures from 5 litres to 0.1 litres.
g) One electric oven with thermostat upto 120 Deg cent.
h) One flakiness gauge
i) One elongation index gauge
j) One sedimentation pipette
k) One pyconometer
l) Two calibrated glass jar of 1 litre capacity.

2.6.2 Arrangement can be made by the contractor to have the cubes tested in an approved laboratory in
lieu of a testing machine at site at his expense, with the prior consent of the Engineer.

2.6.3 At least 6 test cubes of each class of concrete shall be made fore very 15 cu.m of concrete or part
thereof. Such samples shall be drawn on each day for each type of concrete. Of each set of 6 cubes,
three shall be tested at 7 days age and three at 28 days age. The laboratory test results shall be
tabulated and furnished to Engineer. Engineer will pass the concrete if average strength of the
specimens tested is not less than the strength specified, subject to the condition that only one out of
three consecutive tests may give a value less than the specified strength but this shall not be less than
90% of the specified strength. The cubes shall be tested on 7 th and 28 th day from the day of casting
of the cubes.

2.7 Admixtures

2.7.1 Admixtures may be used in concrete only with the approval of the Engineer based upon evidence
that, with the passage of time, neither the compressive strength nor its durability reduced. Calcium
chloride shall not be used for accelerating setting of the cement for any concrete containing
reinforcement, or embedded steel parts. When Calcium chloride is permitted to be used, such as in
mass concrete works, it shall be dissolved in water and added to the mixing water in an amount not
to exceed 1.5% of the volume of cement in concrete. When admixtures are used, the designed
concrete mix shall be corrected accordingly. Admixtures shall be used as per manufacturer’s
instructions and in the manner and with the control specified by the Engineer in charge.

2.7.2 Air Entraining agents

Where specified and approved by the Engineer, neutralized vinyl resin or any other approved air
entraining agent may be used to produce the specified amount of air in the concrete mix and these
agents shall conform to the requirements of ASTM standard 6260, air entraining admixtures for
concrete. The recommended total air content of the concrete is 4% plus/minus 1%.The method of
measuring air content shall be as per IS 1199.

2.7.3 Water reducing admixtures

Where specified and approved by the engineer in charge water reducing lignosulfonate mixture shall
be added in quantities specified by the Engineer. The admixtures shall be added in the form of a
solution.
 - 12 -

2.7.4 Retarding admixtures

Where specified and approved by the Engineer in charge water proofing agent conforming to IS
2645 shall be added in quantities specified by the Engineer

2.8 Optional tests

2.8.1 Engineer in charge may order tests to be carried out on cement, sand, coarse aggregate and water in
accordance with the relevant Indian Standards.

Tests on cement shall include

1) Fineness test
2) Test for normal consistency
3) Test for setting time
4) Test for soundness
5) Test for tensile strength
6) Test for compressive strength
7) Test for heat of hydration by experiment and by calculations in accordance with IS 269

Tests on sand shall include

1) Sieve test
2) Test for organic impurities
3) Decantation test for determining clay and silt content
4) Specific gravity test
5) Test for unit weight and bulkage factor

Tests on coarse aggregate shall include

1) Test for sieve analysis
2) Specific gravity and unit weight of dry loose and rodded aggregate
3) Soundness and alkali aggregate reactivity
4) Pertrographic examination
5) Deleterious materials and organic impurities
6) Test for aggregate crushing value

Any or all these tests would normally be ordered to be carried out only if Engineer feels the
materials are not in accordance with the specifications or if the specified concrete strengths are not
obtained and shall be performed by the contractor at site or at an approved test laboratory.

2.8.2 If the work cubes do not give the stipulated strengths Engineer in charge reserves the right to ask the
contractor to dismantle such portions of work which in his opinion are unacceptable and redo the
work to the standard stipulated at contractor’s cost.

2.9 Preparation prior to concrete placement

2.9.1 Before the concrete is actually placed in position, the insides of the form work shall be inspected to
see that they have been cleaned and oiled. Temporary openings shall be provided to facilitate
inspection, especially at bottom of columns and walls forms to permit removal of saw dust, wood
shavings, binding wire, rubbish dirt, etc. Openings shall be placed or holes drilled so that these
materials and water can be removed easily. Such openings/holes shall be later suitably plugged.

2.9.2 The various agencies shall be permitted ample time to install drainage and plumbing lines in floor
and trench drains, conduits, hangers, anchors, inserts, sleeves, bolts, frames and other miscellaneous
embedments to be cast in the concrete as indicated on the drawings or as is necessary for the proper
execution of the work. Contactor shall cooperate fully with all such agencies and shall permit the use
of scaffolding formwork, etc., by other agencies at no extra cost.

2.9.3 All embedded parts, inserts, etc., supplied by owner or contractor shall be correctly positioned and
securely held in the forms to prevent displacement during depositing and vibrating of concrete.

2.9.4 Anchor bolts shall be positioned and kept in place with the help of properly manufactured templates.
The use of all such templates, fixtures, etc., shall be deemed to be included in the rates.
 - 13 -

2.9.5 Slots, openings, holes, pockets, etc., shall be provided in the concrete work in the positions indicated
in the drawings or as directed by the Engineer in charge.

2.9.6 Prior to concrete placement all work shall be inspected and approved by Engineer and if found
unsatisfactory, concrete shall not be poured until after all defects have been corrected at contractor’s
cost. Cat ladders shall be provided on the reinforcement to facilitate labour movement.

2.9.7 Approval by Engineer for all materials and work as required herein shall not relieve contractor from
his obligation to produce finished concrete in accordance with the drawings and specifications.

2.9.8 No concrete shall be placed in wet weather or on water covered surface. Any concrete that has been
washed by heavy rains, the work shall be entirely removed, if there is sign of cement and having
been washed from the concrete mixture. To guard against damage which may be caused by rains ,
the works shall be covered with tarpaulins immediately after the concrete has been placed and
compacted. Any water accumulating on the surface of the newly placed concrete shall be removed
by approved means and no further concrete shall be removed by approved means and no further
concrete shall be placed thereon until such water is removed. To avoid flow of water over/around
freshly placed concrete, suitably drains and sumps shall be provided.

2.9.9 Immediately before concrete placement begins, proposed surfaces except framework, which will
come in contact with the concrete to be placed, shall be covered with a bonding mortar.

2.10 Transportation

2.10.1 All buckets, containers or conveyors used for transporting concrete shall be mortar tight. Irrespective
of the method of transportation adopted, concrete shall be delivered with the required consistency
and plasticity without segregation or loss of slump. However, chutes shall not be used for
transportation of concrete without the written permission of Engineer and concrete shall not be
rehandled before placing.

2.10.2 Concrete must be placed in its final position before it becomes too stiff to work. On no account,
water shall be added after the initial mixing of concrete which has become stiff or has been
contaminated with foreign materials shall be rejected and disposed off as directed by the Engineer.

2.10.3 All equipment used for mixing, transporting and placing of concrete shall be maintained in clear
condition. All pans, buckets, hoppers, chutes, pipelines and other equipment shall be thoroughly
cleaned after each period of placement.

2.11 Procedure for placing of concrete

2.11.1 Before any concrete is placed, the entire placing programme, consisting of equipment, layout,
proposed procedures and methods shall be submitted to Engineer for approval if so demanded by
Engineer and no concrete shall be placed until Engineer’s approval has been received. Conveyor for
conveying concrete shall be of such size and design as to ensure a practically continuous flow of
concrete during depositing without segregation of materials, considering the size of the job and
placement location.

2.11.2 Concrete shall be placed in its final position before the cement shall normally be compacted in its
final position within thirty minutes of leaving the mixer and once compacted it shall not be
disturbed.

2.11.3 Concrete, in all cases, be deposited as nearly as practicable

2.11.4 Except when otherwise approved by Engineer, concrete shall be placed in shovels or other approved
implements and shall not be dropped from a height more than 1 m or handled in a manner which will
cause segregation.

2.11.5 The following specification shall apply when placing of concrete by use of mechanical equipment is
specifically called for while inviting bids or is warranted considering the nature of work involved.
The control of placing shall begin at the mixer discharger, concrete shall be discharged by a vertical
 - 14 -

drop into the middle of the bucket or hopper and this principle of a vertical discharge of concrete
shall be adhered to thoroughly all stages of delivery until the concrete comes to rest in its final
position.

2.11.6 Central bottom dump buckets of a type that provides for positive regulation of the amount and rate
of deposition of concrete in all dumping position shall be employed.

2.11.7 In placing concrete in large open areas, the bucket shall be spotted directly over the position
designated and then lowered for dumping. The open bucket shall clear the concrete already in place
and the height of drop shall not exceed 1 m. The bucket shall be opened slowly to avoid height
vertical bounce. Dumping pf buckets on the swing or in any manner which results in separation of
ingredients or disturbance of previously placed concrete will not be permitted.

2.11.8 Concrete placed in restricted forms by wheel barrows, buggies, cars, short chutes or hand shoveling
shall be subject to the requirement for vertical delivery of limited height to avoid segregation and
shall be deposited as nearly as practicable in its final position.

2.11.9 Where it is necessary to use transfer chutes, specific approval of Engineer must be obtained to the
type, length, slopes, baffles, vertical terminals and timing of operations, the discharge and without
segregation. To allow for the loss of mortar against the sides of the chutes, the first mix shall have
less coarse aggregate. During cleaning of chutes the waste water shall be kept clear of the forms.
Concrete shall not be permitted to fall from the end of the chutes by more than 1 m. Chutes when
approved for use shall have slopes not flatter than 1:2. Chutes shall be of metal or metal lined and of
rounded cross section. The slopes of all chutes sections shall be approximately the same. The
discharge end of the chutes shall be maintained above the surface of the concrete in the forms.

2.11.10 Concrete may be conveyed and placed by mechanically operated equipment eg. Pumps or pneumatic
placers only with the written permission of the Engineer. The slump shall be held to the minimum,
necessary for conveying concrete by this method.

2.11.11 When pumping is adopted, before pumping of concrete is started, the pipeline shall be lubricated
with one or two batches of mortar composed of one part cement and two parts sand. The concrete
mix shall be specially designed to suit pumping. Care shall be taken to avoid stoppages in work once
pumping has started.

2.11.12 When pneumatic placer is used, the manufacturer’s advice on layout of pipeline shall be followed to
avoid blockages and excessive wear. Restraint shall be provided at the discharge box to cater for the
reaction at this end. Manufacturer’s advice shall be followed regarding concrete quality and all other
related matters when pumping or pneumatic placing equipment are used.

2.11.13 Concreting once started, shall be continuous until the pour is completed. Concrete shall be placed in
successive horizontal layers of uniform thickness ranging from 15 to 90 mm as directed by the
Engineer. These shall be placed as rapidly practicable to prevent the formation of cold joints or
planes of weakness between each succeeding layer within the pour. The thickness of each layer shall
be such that it can be deposited before the previous layer has stiffened. The bucket loads or other
units of deposit shall be spotted progressively along the face of the layer with such overlap as well
facilitate spreading the layer to uniform depth and texture with a minimum of shoveling. Any
tendency to segregation shall be corrected by shoveling stones into mortar rather than mortar on to
stones. Such a condition shall be corrected by redesign of mix or other means, as directed by
Engineer.

2.11.14 The top surface of each pour and bedding planes shall be approximately horizontal unless otherwise
instructed.

2.12 Compaction

2.12.1 Concrete shall be compacted during placing with approved vibrating equipment until the concrete
has been consolidated to the maximum practicable density, is free of pockets of coarse aggregate and
fits tightly against all form surfaces, reinforcement and embedded fixtures. Particular care shall be
taken to ensure that all concrete placed against the forms faces and into corners of forms or against
hardened concrete at joints is free from voids or cavities. The use of vibrators shall be consistent
 - 15 -

with the concrete mix and caution exercised not to over-vibrate the concrete to the point that
segregation results.

2.12.2 Vibrators shall conform to IS specifications. Type of vibrator to be used shall depend on the
structure where concrete is to be placed. Shutter vibrators to be effective, shall be firmly secured to
the formwork which must be sufficiently rigid to transmit the vibration and strong enough not to be
damaged by it. Immersion vibrators shall have no load frequency, amplitude and acceleration as per
IS 2505 depending on the size of the vibrator. Immersion vibrators in sufficient numbers and each of
adequate size shall be used to properly consolidate all concrete.

2.12.3 The exact manner of application and the most suitable machines for the purpose must be carefully
considered and operated by experienced men. Immersion vibrators shall be inserted vertically at
points not more than 450 mm apart and withdrawn when air bubbles cease to come to the surface.
Immersion vibrators shall be withdrawn very slowly. In no case shall immersion vibrators be used to
transport concrete inside the forms. Particular attention shall be paid to vibration at the top of a lift
e.g. in a column or wall.

2.12.4 When placing concrete in layers, which are advancing horizontally as the work progresses, great
care shall be exercised to ensure adequate vibration, blending and mixing of the concrete between
the succeeding layers.

2.12.5 The immersion vibrator shall penetrate the layer being placed and also penetrate the layer below
with the under layer is still plastic to ensure good bond and homogeneity between the two layers and
prevent the formation of cold joints.

2.12.6 Care should be taken to prevent contact of immersion vibrators against reinforcement steel.
Immersion vibrators shall not be allowed to come in contact with the reinforcement steel after start
of initial set. They shall also be not allowed to come in contact with forms or finished surfaces.

2.12.7 Form attached vibrators shall be used only with specific authorization of the Engineer.

2.12.8 The surface vibrators will not be permitted under normal conditions. However for thin slabs
vibration by specially designed vibrators may be permitted upon approval of Engineer

2.12.9 The formation of stone pockets or mortar bondages in corner and against faces of forms shall not be
permitted. Should these occur, they shall be dug out, reformed and refilled to sufficient depth and
shape for thorough bonding, as directed by Engineer.

2.13 Placement Interval

Except when placing slip forms each placement of concrete in multiple lift work, shall be allowed to
set for at least 24 hours after the final set of concrete and before the start of a subsequent placement.

2.14 Special provision in placing

When placing concrete in walls with openings and in floors of integral slab and beam construction
and other similar conditions, the placing shall stop when the concrete reaches the top of the openings
in walls and bottom horizontal surface of the slab, as the case may be placing shall be resumed
before the concrete in place takes initial set, but not until it has time to settle as determined by
Engineer.

2.15 Placing concrete through reinforcement steel

When placing concrete through reinforcement steel, care shall be taken to prevent segregation of the
coarse aggregate. When the congestion of steel makes placing difficult it may be necessary to
temporarily move the top steel aside to get proper placement and restore reinforcing steel to design
position.
 - 16 -

2.16 Bleeding

Bleeding of free water, on top of concrete being deposited, in to the forms shall be caused to stop the
concrete pour. The conditions causing this defect corrected before any further concreting is resumed.

2.17 Curing, protecting, repairing and finishing

2.17.1 Curing

2.17.1.1 All concrete shall be cured by keeping it continuously damp for a period of time required for
complete hydration and hardening to take place. Preference shall be given to the use of continuous
sprays or ponded water continuously saturated covering of sacks, canvas, hessian, polythene sheets
or other absorbent materials, or approved effective curing compounds applied with spraying
equipment capable of producing a smooth, even textured coat. Extra precautions shall be exercised
in curing concrete during cold and hot water as outlined herein after. The quality of curing water
shall be the same as that used for mixing concrete.

2.17.1.2 Certain types of finish or preparation for overlaying concrete must be done at certain stage of the
curing process and special treatment may be required for specific concrete surface finish.

2.17.1.3 Curing of concrete made of high alumina cement and supersulphated cement shall be carried out as
directed by the Engineer.

2.17.1.4 Fresh concrete shall be kept continuously wet for a minimum period of 15 days from the date of
placing of concrete following a lapse of 12 to 14 hours after laying of concrete. The curing of
horizontal surfaces exposed to the drying winds shall however begin immediately the concrete has
hardened. Water shall be applied to formed surfaces immediately upon removal of forms. Quality of
water applied shall be controlled so as to prevent erosion of freshly placed concrete

2.17.1.5 Curing shall be assured by use of an ample water supply under pressure in pipes with all necessary
appliances of hose, sprinklers and spraying devices. Continuous fine mist spraying or sprinkling
shall be used, unless otherwise specified or approved by the Engineer.

2.17.1.6 Whenever, by the judgement of the Engineer, it may be necessary to omit the continuous spray
method, a covering of clean sand or other approved means such as wet gunny bags which will
prevent loss of moisture from the concrete during or after the curing period. Covering shall be kept
continuously wet during the curing period.

2.17.1.7 For curing of concrete in pavements, side-walks floors, flat roofs or other level surfaces, the ponding
method of curing is preferred. The method of containing the ponded water shall be approved by the
Engineer. Special attention shall be given to edges and corners of the slabs to ensure proper
protection to these area. The ponded area shall be kept continuously filled with water during the
curing period.

2.17.1.8 Surface coating type compounds shall be used only by special permission of Engineer, curing
compounds shall be liquid type white pigmented. Other curing compounds shall be used on surfaces
where future blending with concrete, water or acid proof membrane or painting is specified.

2.17.1.9 All equipment and materials required for curing shall be on hand and ready for use before concrete is
placed.

2.17.2 Protecting fresh concrete

2.17.2.1 Fresh concrete shall be protected from defacements and damage due to construction operation by
leaving forms in place for an ample period as specified later in this application. Newly placed
concrete shall be protected by approved means such as tarpaulins from rain, sun and winds. Steps as
approved by Engineer shall also be taken to protect immature concrete from damage by debris,
excessive loading, vibration, abrasion or contact with other materials, etc., that may impair the
strength and/or durability of the concrete. Workmen shall be warned against and prevented from
disturbing green concrete during its setting period. If it is necessary that workmen enter the area of
freshly placed concrete, Engineer may require that bridges be placed over the area.
 - 17 -

2.17.3 Repair and replacement of unsatisfactory concrete

2.17.3.1 Immediately after the shuttering is removed, the surface of concrete shall be very carefully inspected
and all defective areas called to the attention of Engineer who may permit patching of the defective
areas or also reject the concrete unit either partially or entirely. Rejected concrete shall be removed
and replaced by contractor at no additional expense to owner. Holes left by form bolts, etc., shall be
filled up and made good with mortar composed of one part of cement to one and half parts of sand
passing 2.36 mm IS sieve after removing any loose stones adhering to the concrete shall be finished
as described under the particular items of work.

2.17.3.2 Superficial honey combed surfaces and rough patches shall be similarly made good immediately
after removal of shuttering in the presence of Engineer and superficial water and air holes shall be
filled in. The mortar shall be well worked into the surface with a wooden float. Excess water shall be
avoided. Unless instructed otherwise by Engineer the surface of the exposed concrete placed against
shuttering be rubbed down immediately on removal of shuttering to remove fine or other
irregularities and necessary care being taken to avoid damage to the surface. Surface irregularities
shall be removed by grinding.

2.17.3.3 If reinforcement is exposed or the honey combing occurs at vulnerable positions eg. Ends of beams
or columns it may be necessary to cut out the member completely or in part and reconstruct. The
decision of the Engineer shall be final in this regard. If only patching is necessary, the defective
concrete shall be cut out till solid concrete is reached (or to a minimum depth of 25 mm) the edges
being cut perpendicular to the affected surface or with small under cut if possible. Anchors, tees or
dovetail slots shall be provided whenever necessary to attach the new concrete securely in place an
area extending several centimeters beyond the edges and the surfaces of the prepared voids shall be
saturated with water for 24 hours immediately before the patching material is placed.

2.17.3.4 The use of epoxy for bonding fresh concrete used for repairs will be permitted upon written approval
of Engineer. Epoxy shall be applied in strict accordance with the instructions of the manufacturer.

2.17.3.5 Small size holes having surface dimensions about equal to the depth of the hole, holes left after
removal of form bottom, grout insert holes and slots cut for repair of cracks shall be repaired as
follows. The hole to be patched shall be roughened and thoroughly soaked with clean water until
absorption stops.

2.17.3.6 A 5 mm thick layer of grout of equal parts of cement and sand shall be well brushed into the surface
to be patched, followed immediately by the patching concrete which shall be well consolidated with
a wooden float. The concrete patch shall be built up in 10 mm thick layers. After an hour or more,
depending upon weather conditions, it shall be worked off flush with a wooden float and smooth
finish obtained by wiping with hessian, a steel trowel shall be used for this purpose. The mix for
patching shall be of same materials and in the same proportions as that used in the concrete being
repaired, although some reduction in the maximum size of the coarse aggregates may be necessary
and the mix shall be kept as dry as possible.

2.17.3.7 Mortar filling by air pressure (guniting) shall be used for repairing of areas too large and/or too
shallow for patching with mortar. Patched surfaces shall be given a final treatment to match the
colour and texture of the surrounding concrete. While cement shall be substituted for ordinary
cement, if so directed by Engineer, to match the shade of the patch with original concrete.

2.17.3.8 The patched area shall be covered immediately with an approved non-staining water saturated
material such as gunny bag which shall be kept continuously wet and protected against sun and wind
for a period of 24 hours. Thereafter, the patched area shall be kept wet continuously by fine spray of
sprinkling for not less than 10 days.

2.17.3.9 All materials, procedures and preparation used in the repairing of concrete and also the finished
repair work shall be subject to the approval of Engineer. All fittings shall be tightly bonded to the
concrete and shall be sound, free from shrinkage cracks after the fillings have been cured and
finished.
 - 18 -

2.17.4 Finishing

2.17.4.1 The type of finish for formed concrete surface shall be as follows, unless, otherwise specified by the
Engineer.

2.17.4.2 For surfaces against which backfill or concrete is to be placed, no treatment is required except
repairing of defective area.

2.17.4.3 For surface below grade which will receive waterproofing treatment the concrete shall be free of
surface irregularities which would interfere with proper application of the waterproofing material
which is specified for use.

2.17.4.4 Unless specified, surfaces which will be exposed when the structure is in service shall receive no
special finish, except repairing of damage or defective concrete removal of fins and abrupt
irregularities, fillings of holes let by form ties and rods and clean up of loose or adhering debris.

2.17.4.5 Surfaces which will be exposed to the weather and which would normally be level shall be sloped
for drainage. Unless the drawing specifies such as stair treads, walls shall be sloped across the width
approximately 1 in 30 broader surface such as walkways, roads, parking areas and platforms shall be
sloped about 1 in 50. Surfaces that will be covered by backfill or concrete sub floors to be covered
either concrete topping, terrazzo or quarry tile and similar surfaces shall be smooth screeded and
leveled to produce even surfaces. Surface irregularities shall not exceed 6 mm. surfaces which will
not be covered by backfill, concrete or tile toppings such as outside decks, floors of galleries and
sumps, parapets, gutters, sidewall floors and slabs shall be consolidated, screeded and floated.
Excess water and laitance shall be removed before finishing. Floating may be done with hand or
power tools and started as the screeded surface has attained a stiffness to permit finishing operation
and these shall be the minimum required to produce a surface uniform in texture and free from
screed marks or other imperfections. Joints, edges panels and forms lining shall be of uniform size
and be as large as practicable and installed with closed joints. Upon removal of forms the joint
marks shall be smoothened off and all blemishes, projections etc., removed leaving the surfaces
reasonably smooth and unmarked.

2.17.4.6 Integral cement concrete finish

When specified on the drawings and integral cement finish of specified thickness for floors and slabs
shall be applied either monolithic or bonded as specified on the drawings as per IS 2571. The surface
shall be compacted and then floated with a wood float or power floating machine. The surface shall
be tested with a straight edge and any high or low spots eliminated. Floating or toweling of finish
shall be permitted only after all the surface water has evaporated. Dry cement or a mixture of dry
cement and sand shall not be sprinkled directly on the surface of the cement finish to absorb
moisture or to stiffen the mix.

2.17.4.7 Exposed Concrete finish/Rendering

A rubbed finish shall be provided only on exposed concrete surfaces as specified on the drawings.
Upon removal of forms, all fins and other projections on the surfaces shall be carefully removed,
off-sets leveled and voids and damaged sections be immediately saturated with water and repaired
by filling with a concrete or mortar of the same composition as was used in the surface. Then surface
shall be thoroughly wetted and rubbed with carborundum or other abrasive. Cement mortar may be
used in the rubbing, but the finished surface shall be brush coated with either cement grout after
rubbing. The finished surfaces shall present a uniform and smooth appearance.

2.18 Form Work

2.18.1 The formwork shall consist of shores, bracings, sides of beams and columns, bottom of slabs, etc.,
including ties anchors, hangers inserts, etc., complete which shall be properly designed and planned
for the work. False work shall so be constructed that necessary adjustment can be made to
compensate for take up and settlements. Wedge may be used at the top or bottom of timber shores
but not at both ends to facilitate vertical adjustment or dismantling of the formwork.
 - 19 -

2.18.2 Design of formwork

The design of the formwork as well as its construction shall be the responsibility of the contractor. If
so instructed, the drawings and/or calculation for the design for the formwork shall be submitted to
the Engineer for approval before proceeding with the work, at no extra cost. Engineer’s approval
shall not however relieve contractor of the full responsibility for the design and construction of the
formwork. The design shall take into account all the vertical and lateral that the forms will be
carrying live and vibration loadings.

2.18.3 Type of formwork

Formwork may be of timber, plywood, metal, plastic or concrete. For special finishes the formwork
may be lined with plywood, steel, sheets, oil, tempered hardboard, etc. Sliding forms and slip forms
may be used with the approval of the Engineer.

2.18.4 Formwork requirements

2.18.4.1 Forms shall conform to shapes, lines, grades and dimensions including camber of the concrete as
called for on the drawings. Ample studs, braces, ties, straps, etc., shall be used to hold the forms in
proper position without any distortion whatsoever until the concrete is set sufficiently to permit
removal of forms. Forms shall be strong enough to permit the use of immersion vibrators. In special
cases form vibrators may also be used. The shuttering shall be close boarded. Timber shall be well
seasoned, free from sap, shakes, loose knots, worm holes, warps or other surface defects in contact
with concrete. Faces coming in contact with the concrete shall be free from adhering grout, plaster,
paint, projecting nails, splits or other defects. Joints shall be sufficiently tight splits or other defects.
Joints shall be sufficiently tight to prevent loss of water or any fine material from concrete.

2.18.4.2 Plywood shall be used for exposed concrete surfaces; where called for. Sawn and wrought timber
may be used for unexposed surfaces. Inside faces of forms for concrete surfaces which are to be
rubbed finished shall be planned to remove irregularities or unevenness in the face. Form work with
linings shall be permitted.

2.18.4.3 All new and used form timber shall be maintained in a good condition with respect to shape,
strength, rigidity, water tightness, smoothness and cleanliness of surfaces. Form timber
unsatisfactory in any respect shall not be used and if rejected by Engineer shall be removed from the
site.

2.18.4.4 Shores supporting successive members shall be placed directly over those below or be so designed
and placed that the load will be transmitted directly to them. Trussed supports shall be provided for
shores that cannot be secured on adequate foundations.

2.18.4.5 Formwork, during any stage of construction shoeing signs of distortion an distorted to such a degree
that the indented concrete work will not conform to the exact contours indicated on the drawings,
shall be repositioned and strengthened. Poured concrete affected by the faulty formwork, shall be
removed completely and the formwork be corrected prior to placing of new concrete.

2.18.4.6 Excessive construction camber to compensate for shrinkage, settlement may impair the structural
strength of members and shall not be permitted.

2.18.4.7 Forms shall be so designed that their removal will not damage the concrete. Face formwork shall
provide true vertical and horizontal joints, conform to the architectural features of the structure as to
location of joints and be as directed by the Engineer.

2.18.4.8 Where exposed smooth or rendered concrete finishes are required the forms shall be constructed
with special care so that the resulting concrete surfaces require a minimum finish..

2.18.5 Form work for Slope Surfaces

2.18.5.1 Forms for sloped surfaces shall be built so that the boards can be removed one by one from the
bottom up as soon as the concrete has attained sufficient stiffness to prevent sagging. Surfaces of
 - 20 -

construction joints and finished surfaces with slopes steeper than 4 horizontal: 1 vertical shall be
formed as required herein

2.18.6 Form work for Curved Surfaces

2.18.6.1 The contractor shall interpolate sections as necessary and shall construct the forms so that the
curvature will be continuous between sections. Where necessary to meet requirements for curvature,
the form timber shall be built up of laminated splines cut to make tight, smooth form surfaces.

2.18.6.2 After the forms have been constructed, all surface imperfections shall be corrected and all surface
irregularities at matching faces of form material shall be dressed to the specified curvature.

2.18.7 Formwork for Exposed Concrete Surfaces

2.18.7.1 Where it is desired, directed or shown on the drawings to have original fair face finish of concrete
surface without any rendering or plastering, formwork shall be carried out by using wood planks,
plywood or steel plates of approved quality and as per the direction of the Engineer.

2.18.7.2 The contractor shall use one type of material for all such exposed concrete faces and the forms shall
be constructed so as to produce uniform and consistent texture and pattern on the face of the
concrete. Patches or forms for these surfaces will not be permitted. The formwork shall be placed so
that all horizontal formworks are continuous across the entire surface.

2.18.7.3 To achieve a finish which shall be free of board marks, the formwork shall be faced with plywood or
equivalent material in large sheets. The sheets shall be arranged to coincide with architectural
features, cills, window heads or change in direction of the surface. All joints between shuttering
plates or panels shall be vertical or horizontal unless otherwise directed. Suitable joints shall be
provided between sheets. The joints shall be arranged and fitted so that no blemish or mark is
imparted to the finished surfaces.

2.18.7.4 To achieve a finish which shall give the rough appearance of concrete cast against sawn boards,
formwork boards unless otherwise stated shall be of 150 mm wide, securely jointed with tonge and
grooved joints if required to prevent grout loss with tie rod positions and direction of boards
carefully controlled. Sawn boards shall be set horizontally, vertically or at an inclination shown in
the drawings. All bolt holes shall be accurately aligned horizontally and vertically and shall be filled
with matching mortar recessed 5 mm back from the surrounding concrete face.

2.18.7.5 Forms for exposed concrete surfaces shall be constructed with grade strips (the underside of which
indicated top of pour) at horizontal construction joints, unless the use of groove strips is specified on
the drawings. Such forms shall be removed and reset from lift to lift; they shall not be continuous
from lift to lift. Sheeting of reset forms shall be tightened against the concrete so that the forms will
not be spread and permit abrupting irregularities or loss of mortar. Supplementary form ties shall be
used as necessary to hold the reset forms tight against the concrete.

2.18.7.6 For fair faced concrete, the position of through bolts will be restricted and generally indicated on the
drawings.

2.18.7.7 Chamfer strips shall be placed in the corners of forms for exposed exterior corners so as to produce
20 mm beveled edges except where otherwise shown in the drawings. Interior corners and edges at
formed joints shall not be beveled unless shown on the drawings. Mouldings for grooves, drip
courses and bands shall be made in the form itself.

2.18.7.8 The wood planks, plywood and steel plates used in formwork for obtaining exposed surfaces shall
not be used for more than 3 times in case of wood planks, 6 times for plywood and 10 times for steel
plates respectively. However, no forms will be allowed for reuse, if in the option of the Engineer it is
doubtful to produce desired texture of exposed concrete.

2.18.7.9 In order to obtain exposed concrete work of uniform color it shall be necessary to ensure that the
sand used for all exposed concrete work shall be of approved uniform colour. Moreover the cement
used in the concrete for any complete element shall be from single consignment.
 - 21 -

2.18.7.10 No exposed concrete surface shall be rendered or painted with cement or otherwise. Plastering of
defective concrete as a means of achieving the required finish shall not be permitted, except in the
case of minor porosity on the surface; the Engineer may allow a surface treatment by rubbing down
with cement and sand mortar of the same richness and colour as for the concrete. This treatment
shall be made immediately after removing the formwork.

2.18.8 Bracing Struts and props

2.18.8.1 Shuttering shall be braced, strutted, propped and so supported that it shall not deform under weight
and pressure of the concrete and also due to the movement of men and other materials. Bamboos
shall not be used as props or cross bearers.

2.18.8.2 The shuttering for beams and slabs shall be so erected that the shuttering on the sides of the beams
and under the soffit of slabs can be removed without disturbing the beam bottoms. Repropping of
beams shall not be done except when props have to be reinstated to take care of construction of
loads anticipated to be in excess of the design load. Vertical props shall be supported on wedges or
other measures shall be taken whereby the props can be generally lowered vertically while striking
the shuttering. If the shuttering for a column is erected for the full height of a column, one side
shall be left open and built up in sections as placing of concrete from the sides to limit the drop of
concrete to 3 m or as directed by the Engineer.

2.18.9 Mould oil

Care shall be taken to see that the faces of formwork coming in contact with concrete are perfectly
cleaned and two coats of mould oil or any other approved material applied before fixing
reinforcement and placing concrete. Such coating shall be insoluble in water, non staining and not
injurious to concrete. It shall not become flaky or be removed by rain or wash water.
Reinforcement and/or other items to be cast in the concrete shall not be placed until coating of the
forms is complete; adjoining concrete surface shall also be protected against contamination from
the coating material.

2.18.10 Chamfers and fillets

All corners and angles exposed in the finished structure shall be formed with moulding to form
chamfers or fillets on the finished concrete. The standard dimension of chamfers and fillers, unless
otherwise specified shall be 20 mm x 20 mm. Care shall be exercised to ensure accurate moldings.
The diagonal face of the mouldings shall be planned or surfaced to the same texture as the forms to
which it is attached.

2.18.11 Wall ties

Wire ties passing through the walls shall not be allowed. In their place bolts through sleeves be
used.

2.18.12 Reuse of forms

Before reuse, all forms shall be thoroughly scraped, cleaned, nails removed, holes that may leak
suitably plugged and joints examined and when necessary, repaired and the inside retreated to
prevent adhesion, to the satisfaction of the Engineer. Warped timber shall be resized. Contractor
shall equip himself with enough shuttering material to complete the job in the stipulated time.

2.18.13 Removal of forms

2.18.13.1 Contractor shall record on the drawings and in a special register the date upon which the concrete
is placed in each part of the work and the date on which the shuttering is removed therefrom. The
contractor shall remove the shuttering after obtaining the approval of the Engineer.

2.18.13.2 In no circumstances shall forms be struck until the concrete reaches the strength of at least twice
the stress due to self weight and any construction/erection loading to which the concrete may be
subjected at the time of striking form work.
 - 22 -

2.18.13.3 In normal circumstances (generally where temperatures are above 20 deg cent) forms may be
removed after the expiry of the following periods:

Ordinary Rapid hardening

Portland cement Portland cement
concrete
a) Walls columns and vertical sides of beams 24 to 48 hours 24 hours
as directed by
the Engineer
b) Slabs prods left under 3 days 2 days
c) Beam soffits prods left under 7 days 4 days
d) Removal of Props to slabs:
i) Spanning upto 4.5 m 7 days 4 days
ii) Spanning over 4.5 m 14 days 8 days
e) Removal of props to beams and arches
i) Spanning up to 6 m 14 days 8 days
ii)Spanning over 6 m 21 days 12 days

2.18.3.4 Striking shall be done slowly with utmost care to avoid damage to arises and projections and without
shock or vibration, by gently erasing the wedges. If after removing the formwork, it is found that
timber has been embedded in the concrete, it shall be removed and made good as specified earlier.

2.18.3.5 Reinforced temporary openings shall be provided as directed by the Engineer to facilitate removal of
formwork which otherwise may be inaccessible.

2.18.3.6 Tie rods, clamps, form bolts etc., which must be entirely removed from walls or similar structures
shall be loosened not sooner than 24 hours nor later than 40 hours after the concrete has been
deposited. Ties, withdrawn from walls and grade beams shall be pulled towards the inside face
cutting ties back from the faces of walls and grade beams shall be pulled towards the inside face
cutting ties back from the faces of walls and grade beams will not be permitted.

2.18.3.7 For liquid retaining structures no sleeves for through bolts shall be used nor shall through bolts be
removed as indicated above. The bolts, in this case, shall be cut at 25 mm depth from the surface and
then the hole shall be made good by sand, cement mortar of the same proportions as the concrete just
after striking the formwork.

2.19 Reinforcement Steel

2.19.1 General

2.19.1.1 Reinforcement bars, if supplies are arranged by contractor, and if not otherwise specified shall be
either plain round mild steel bars grade I as per IS 432(part I) or medium tensile steel bar as per IS
432 (part I) or hot rolled mild steel and medium tensile steel deformed bars as per IS 1139 or cold
twisted steel bars as per IS 1786, as shown and specified on the drawings. Wire mesh or fabric shall
be in accordance with IS 1566. Substitution of reinforcement will not be permitted except upon
written approval from Engineer. All steel bars have to be purchased from SAIL/TISCO/IISCO or
any other approved manufacturer approved by ACCEPTING AUTHORITY. The contractor shall
place direct order on the manufacturing company without involving dealer or distributor.

With each and every delivery of consignment steel, the contractor shall provide the certificate that
the steel conforms to the relevant Indian Standard. Any test required to be carried out on steel at all
stages of construction shall deemed to be included in the contractor’s scope of work. Type of test,
frequency test, acceptance criteria, etc. for steel will be as per specification.
 - 23 -

Weight per metre length of various sizes of MS bars and Tor steel bars are as under:-

Size (Dia) mm Weight: Kg/m Size (Dia) mm Weight: Kg/m

6 0.222 25 3.855
8 0.395 28 4.836
10 0.617 32 6.316
12 0.888 36 7.994
16 1.579 40 9.869
18 1.999 45 12.490
20 2.467 50 15.424
22 2.985

The actual quantity of steel taken for measurement purpose shall be the quantity fixed as per
approved design/drawings or as authorised by the AACCEPTING AUTHORITY including
authorised lap length/chairs, etc. as per the standard sectional weights given in the above table or
actual weight whichever is less. Actual sectional weight of the steel if weighs less than 2 % of the
standard weights shown above shall be rejected. Nothing will be paid extra for wastage and rolling
margin.

The average sectional weight for each diameter shall be arrived at from samples from each lot of
steel received at site. The actual steel consumed shall be worked out by this procedure. The
discretion of the Engineer-in-charge shall be final for the procedure to be followed determining the
average sectional weight of each lot. Quantity of each diameter of steel received at site of work each
day will constitute one single lot for this purpose.

2.19.1.2 Plain round mild steel bars grade II as per IS 432 (part I) may be used with prior approval of
Engineer in writing and with 10% increase in the reinforcement area but its use shall not be
permitted in structures located in earth quake zones subjected to severe damage (as per IS 1895) and
for structures subject to dynamic loading (other than wind loading), such as frames supporting rotary
or reciprocating machinery, etc.

2.19.1.3 All reinforcement shall be clean, free from grease, oil, paint, loose mill scale, loose rust, dust,
bituminous material or any other substances that will destroy or reduce the bond. Al rods shall be
thoroughly cleaned before being fabricated. Pitted and defective rods shall not be used.

2.19.1.4 All concrete works shall be of design mix as defined in IS 456, unless it is a nominal mix concrete
such as 1:3:6, 1:4:8, 1:5:10. Whether reinforced or otherwise, all design mix concrete works to be
carried out under this specification shall be divided into the following classifications.

2.19.2 Providing, fabricating and placing in position reinforcement steel

2.19.2.1 The quality of steel shall be as mentioned in the materials section. The bars shall be as shown
fabricated as per the drawings. Laps and splices for reinforcement shall be as shown on the
drawings. Splices in adjacent bars shall be approved by the Engineer. The bars shall not be lapped
unless the length required exceeds the maximum available lengths of bars at site.

2.19.3 Bending

2.19.3.1 Reinforcing bars supplied bent or in coils, shall be straightened before they are cut into size.
Straightening of bars shall be done in cold and without damaging the bars. This is considered as a
part of reinforcement binding fabricating work.

2.19.3.2 All bars shall be accurately bent according to the sizes and shapes shown on the detailed working
drawings/bar bending schedules. They shall be bent gradually by machine or other approved means.
Reinforcing bars shall not be straightened and rebent in a manner that will injure the material, bars
containing cracks or splits shall be rejected. They shall be bent cold, except bars of over 32 mm in
diameter which may be bent hot if specially approved by the Engineer. Bars bent hot shall not be
heated beyond cherry red colour (not Exceeding 845 deg cent) and after bending shall be allowed to
cool slowly without quenching. Bars incorrectly bent shall be used for straightening and rebending
shall not injure the material. No reinforcement shall be bent when in position in the work without
 - 24 -

approval whether or not it is partially embedded in hardened concrete. Bars having over bends other
than those required by design shall not be used.

2.19.4 Fixing

Reinforcement shall be accurately fixed by any approved means and maintained in the correct
position shown in the drawings by the use of block, spacers and chairs as per IS 2502 to prevent
displacement during placing and compaction of concrete. Bars intended to be in contact at crossing
points shall be strongly bound together at all such points with two no.16 gauge anhealed soft iron
wire. The vertical distance required between successive layers of bar in beams or other members
shall be maintained by providing of mild steel spacer bars at such intervals that the main bars do not
perceptibly sag between adjacent spacer bars.

2.19.5 Cover

2.19.5.1 Unless indicated otherwise on the drawings, clear concrete cover for reinforcement (exclusive of
plaster or other decorative finish) shall be as follows:

a) At each end of reinforcing bar, not less than 25 mm or less than twice the diameter of the
bar whichever is less.
b) For a longitudinal reinforcing bar in a column, not less than 40 mm, nor less than the
diameter of the bar. In case of columns of minimum dimensions of 20 cm or under, with
reinforcing bars of 12 mm and less in diameter, a cover of 25 mm may be used.
c) For longitudinal reinforcing bars in a beam 25 m or less than the diameter of the bar.
d) For tensile, compressive, shear, or other reinforcement in a slab or wall not less than 12 mm
or less than the diameter of such reinforcement
e) For any other reinforcement not less than 12 mm nor less than the diameter of such
reinforcement
f) For footings and other principal structural members in which the concrete is deposited
directly against the ground, cover to the bottom reinforcement shall be 75 mm. If concrete
is poured on a layer of lean concrete the bottom cover may be reduced to 50 mm.
g) For concrete surfaces exposed to the weather or ground after removal of forms, such as
retaining walls, footing sides and top, etc., not less than 50 mm for bars larger than 16 mm
Dia and not less than 40 mm for bars16 mm Dia or smaller.
h) Increased cover thickness shall be provided, as indicated on the drawings, for surfaces
exposed to the action of harmful chemicals (or exposed to earth contaminated by such
chemical, acid, alkali, saline atmosphere sulphurous smoke, etc.
i) For reinforced concrete members, totally or periodically immersed in sea water or subject
to sea water spray, the cover of concrete shall be 50 mm more than those specified in (a) to
(e) above
j) For liquid retaining structures the minimum cover to all steel shall be 40 mm or the
diameter of the main bars, whichever is greater. In the presence of sea water and soils and
waters of a corrosive character the cover shall be increased by 10 mm.
k) Protection to reinforcement in case of concrete exposed to harmful surroundings may also
be given by providing a dense impermeable concrete with approved protective coatings, as
specified by the Engineer.
l) The correct cover shall be maintained by cement mortar cover blocks. Reinforcement for
footings, beams and slabs on sub grade shall be supported on precast concrete blocks as
approved by the Engineer. The use of pebbles and stones shall not be permitted.

2.19.6 Inspection

Erected and secured reinforcement shall be inspected, jointly measured and recorded and approved
by Engineer prior to placement of concrete.
 - 25 -

3.0 MASONRY WORKS

3.1 Applicable codes and specifications

a) The following codes, standards and specifications are made a part of this specification. All
standards, tentative specifications, codes of practices referred to herein shall be the latest
edition including all applicable official amendments and revisions.

IS 1077 - Common burnt clay building bricks

IS 3102 - Classification of burnt clay bricks
IS 2180 - Burnt clay building bricks, heavy duty
IS 3495 - Method of sampling and testing clay building bricks.
IS 2691 - Burnt clay facing bricks
IS 2221 - Code of practice for brick work
IS 2185 - Load bearing hollow concrete blocks
IS 5498 - Lime-cement-cinder hollow concrete blocks
IS 3115 - Lime-cement-cinder solid blocks
IS 1597 - Code of practice for construction of stone masonry (part I)

3.2 Brick

3.2.1 Bricks used in works shall be bricks of specified crushing strength as described in the Schedule of
Quantities. They shall have the following general properties:

3.2.2 They shall be sound, hard, and homogeneous in texture, well burnt in kiln without being verified,
table moulded, deep red, cherry or copper coloured, of regular shape and size and shall have sharp
and square edges and paralled faces. The bricks shall be free from pores, chips, flaws or humps of
any kind. Bricks containing unground particles and which absorb water more than 1/5 th of their
weight when soaked in water for twenty four hours shall be rejected. Over burnt or under burnt
bricks shall be liable to rejection. These bricks shall give a clear ringing sound when struck

3.2.3 Samples of bricks shall be submitted before starting the brickwork to the Engineer for approval.
Bricks supplied shall conform to these approved samples. Brick sample shall be got tested as per
IS:3495 by contractor at no extra cost. Bricks rejected by Engineer shall be removed from the site of
works within 24 hours.

3.3 Mortar

3.3.1 Mix for cement mortar shall be as specified in the respective items of work. Gauge boxes for sand
shall be of such dimensions that one complete bag of cement containing 50 kgs of cement forms one
unit. The sand shall be free from clay, shale, loam, alkali and organic matter and of sound, hard,
clean and durable particles. Sand shall be approved by the Engineer. If so directed by the Engineer
sand shall be thoroughly washed till it is free of any contamination.

3.3.2 For preparing cement mortar the ingredients shall first be mixed thoroughly in dry condition. Water
shall then be added and mixing continued to give a uniform mix of required consistency. Cement
mortar shall preferably be machine mixed, through mixing in a thorough manner may be allowed.
The mortar so mixed shall be used within 30 minutes of mixing. Mortar left unused in the specified
period shall be rejected.

3.3.3 The contractor shall arrange for test on mortar samples if so directed by the Engineer. Retempering
of mortar shall not be permitted.

3.4 Workmanship

3.4.1 All bricks shall be thoroughly soaked in clean water for at least one hour immediately before being
laid. The cement mortar for brick masonry work shall be as specified in the respective item of work.
Brick work 230 mm thick and over shall be laid in English bond unless otherwise specified. While
laying, bricks shall be pressed into the mortar and shoved into final position so as to embed the brick
fully in mortar. Bricks shall be laid with frogs uppermost.
 - 26 -

3.4.2 All brick work shall be plumb, square and true to dimensions. Vertical joints in alternate courses
shall come directly one over the other and be in line. Horizontal courses shall be leveled. The
thickness of brick courses shall be kept uniform. For walls of thickness greater than 230 mm both
faces both faces shall be kept in vertical planes. No broken bricks shall be used except as closers.
Care shall be taken that the bricks forming the top corners and ends of the wall shall be properly
radiated and keyed into position. Holes kept in masonry for scaffolding shall be closed before
plastering. All interconnected brick work shall be carried out at nearly one level ( so that there is
uniform distribution of pressure on the supporting structure) and no portion of the work shall be left
more than one course lower than the adjacent work where this is not possible, the work shall be
racked back accordingly to bond (and not saw toothed) at an angle not exceeding 45 degrees.

3.4.3 Bricks shall be so laid that all joints are well filled with mortar. The thickness of mortar shall not be
less than 6 mm and not more than 10 mm. The face joint shall be racked to a minimum depth of
12mm by raking tools daily during the progress of the work when mortar is still green so as to
provide a proper key for the plaster or pointing is to be done. Where plastering or pointing is not
required to be done the joints shall be uniform in thickness and be struck flush and finished at the
time of laying. The face of brickwork shall be cleaned daily and all mortar droppings removed. The
surface of each course shall be thoroughly cleaned of all dirt before another course is laid on top. If
the mortar in the lower course has begun to set the joints shall be racked out to a depth of 12 mm
before another course is laid.

3.4.4 All brick work shall be built tightly against columns, floor slabs or other structural member.

3.4.5 Where drawings indicate that structural steel columns are to be fire proofed with brick work the
bricks shall be built closely against all flanges and webs with all spaces between the steel and bricks
works filled solid with mortar. Steel members partly embedded in brick work and not indicated to be
fireproof with concrete shall be covered with not less than 12 mm thick mortar unless directed
otherwise by the Engineer.

3.4.6 The work shall be cured for 15 days.

3.4.7 Miscellaneous inserts in masonry e.g. Sleeves, wall ties, anchors, conduits, structural sheet, steel
lintels, etc., shall be installed by the contractor. Furnishing finishing of these inserts by the
contractor will be paid for separately under steel work. Openings, arches etc., shall be provided as
shown on the drawings, chasses, pockets, etc., shall be provided as shown on the drawings to receive
rain water pipes, etc. Wall ties and flashings shall be built into the brick work in accordance with the
drawings and specifications.

3.5 Rubble Masonry

3.5.1 Stones for this work shall be hard, durable rock, coarse or fine grained and uniform in colour free
from veins, flaws and other defects and shall conform to IS: 1597(part I). The stones shall be laid in
mortar proportions specified for the particular item of work. Stones shall be got approved.

3.5.2 For all work below ground level the masonry shall be random rubble uncoursed with ordinary quarry
dressed stones or hearting and faced with selected quarry dressed stones.

3.5.3 For all work above ground level the masonry shall be random rubble faced with hammer dressed
stones with squared quoins at joints and corners.

3.5.4 No joints shall tail into the wall, either with a point or to length less than 1.5 times its height. The
thickness of joints shall not exceed12 mm.

3.5.5 Spauls and pinning shall not be allowed to show on the face of the wall. Two bond stones each of
minimum area of 500 sq.cm for every 1 Sq.m of each wall face shall be provided. These shall be
through stones in walls 600 mm thick and under, in walls thicker than 600 mm the length of bond
stones shall be 2/3 times the thickness of walls. The stones for hearting of the wall shall not be less
than 150 mm in any direction. Chips and Spauls shall be wedged in to avoid thick mortar beds and
joints. The wall faces, corners and joints or openings shall be truly vertical the quoins shall be of
selected stones, neatly dressed with chisel to form the required angle and laid header and stretcher
alternatively.
 - 27 -

3.5.6 The exposed face of the work shall be carefully and neatly pointed with mortar in all joints on the
other side the joints shall be neatly struck with trowel while the mortar is fresh,

3.5.7 The mortar for the work shall be as specified in the respective item of work. Curing of masonry shall
continue for a minimum of ten days.

4.0 WOOD WORK

4.1 Applicable codes

1) IS: 4021 - Timber door, window and ventilator frames

2) IS: 2202 - Wooden flush door shutters (solid core type) Part I
3) IS: 1003 - Timber paneled and glazed shutters (Part I & II)
4) IS: 4020 - Method of tests for wooden flush doors: Type tests
5) IS: 1761 - Transparent sheet glass for glazing and framing purposes
6) IS: 3097 - Specification for veneered particle boards (Exterior Grade)

4.2 General

4.2.1 Wood used for all work shall be the best of the respective class specified, and properly seasoned,
suitable for joinery work should be of natural growth, uniform in texture, straight grained, free from
sapwood, dead knots, open shakes, rot, decay and other defects and blemishes.
4.2.2 For joints following principles to be observed:

At the joints the weakness of pieces must be minimum as far as possible. To place each abutting
surface in a joint as neatly as possible, perpendicular to pressure. To form and fit accurately every
pair of surface that comes in contact.

4.2.3 All joining shall be wrought on all the faces and finished off by hand with sand paper with slightly
rounded arises.

4.2.4 The joints shall be pinned with hard wood pins and put together with white lead. Jointing shall be by
means of mortise and tenon or dovetail joints as approved. For external work the joints shall be
coated with white or red lead before the members are put together. For internal joints where there is
no chance of moisture the joint shall be glued. Driving of screws with hammer is prohibited. The
screws shall be soaked in oil before driving them home. The heads of the screws and nails shall be
sunk and puttied.

4.2.5 All joinery work which shall split, fracture, shrink or show flaws or other defects due to
unsoundness, inadequate seasoning or bad workmanship, shall be removed and replaced with sound
materials at the contractor’s expense.

4.2.6 Door frames shall be rebated. All dimensions shall be as per drawings. The verticals of the door
frames shall project about 50 mm below finished floor, surface coming in contact with brick work
shall be painted with bitumen or solignum as directed by the engineer. The door frame shall be
provided with 3 nos MS 230 x 30 x 3 mm flat split hold fasts on each side, respectively. These hold
fasts shall be embedded in masonry or concrete work with concrete block of mix 12:2:4 and size
230x 300x250. The work shall conform to IS :4021.

4.2.7 The door shall be paneled or solid flush doors or as described in the item of work. All doors shall be
supplied with approved fittings such as hinges, mortice lock of approved make with handles on
sides, oxidized brass tower bolts and latch arrangements, door stops, etc., and as shown in the
drawings. External flush doors shall be made of weatherproof plywood as per item description in the
schedule of quantities.

4.2.8 The workmanship of all doors and window shutters shall conform to the requirements IS :
1003( parts I &II)and IS : 2202 (Part I ). Flush door panels shall be got tested as per IS :4020 in
standard laboratories
 - 28 -

4.2.9 Beading and architraves shall conform to the shapes shown on drawings or as approved and fixed by
means of screws (counter sunk or otherwise) or bolts.

4.3 Glass

4.3.1 Sheet glass or plate glass shall be of Indian make as specified in the schedule of quantities/ as
directed. It shall be free from waves and bubbles and all defects. The thickness of the glass shall be
as follows:

2 mm thick glass for panes upto 900 sq.cm area.

3 mm thick glass for panes from 900-5500 sq.cm area.
4 mm thick glass for panes from 5500-8400 sq.cm area.
5.5 mm thick glass or plate glass for panes above 8400 sq.cm area.

4.3.2 It should be clearly understood that glass which does not have uniform refractive index or which is
wavy, will be rejected. The glazing shall be fixed with teak wood beading and putty.

4.3.3 It shall conform to IS: 1761. The putty shall be made up of one part white lead, 3 parts of finely
powdered chalk and adding boiled linseed oil to make a stiff elastic paste. No voids shall be left in
the putty. Wood work shall not be painted, oiled or otherwise treated before it has been approved by
the engineer.

4.3.4 The window frame shall be provided with 2 nos MS 230x30x3 mm flat split hold fasts on each side ,
respectively. These hold fasts shall be embedded in masonry or concrete work with concrete block
of mix 1:2:4 and size 230x300x250 mm.

4.3.5 The type of windows shall be as specified. Each leaf of the shutter shall have one pair of hinges for a
width of less than or equal to 2 feet, for width more than 2 feet extra nos of hinges shall be provided
as directed by the engineer at no extra cost. The glazed windows shall be provided with glass of
thickness as specified in the item description. Architraves shall be provided as per drawing.

5.0 FINISHING WORKS

5.1 Applicable Codes

1) IS:2394- Code of practice for application of lime plaster finish

2) IS: 1477- Code of practice for painting of ferrous metals in buildings and allied finishes
(part I & II)
3) IS: 427 – Distemper, dry colour as required
4) IS:2395 – Code of practice for painting concrete, masonry and plaster surfaces
5) IS:428 – Distemper, oil emulsion, colour as required

5.2 Plastering

5.2.1 The surface to be plastered shall be washed with fresh clean water free from all dirt, loose material
grease, etc., and thoroughly wetted for 6 hours before plastering work is commenced. Concrete
surfaces to be plastered will however be kept dry. The wall should not be too wet but only damp at
the time of plastering. The damping shall be uniform to get uniform bond between the plaster and
the wall. The junction between the brick work and RCC should be fixed with chicken wire mesh/
PVC strip as directed before plaster.

5.2.2 The proportion of the plaster shall be as specified under the respective items of work. Cement shall
be mixed thoroughly in dry condition and then just enough water added to obtain a workable
consistency. The quality of water, sand and cement shall be as mentioned in the specifications for
Concrete and allied works. The mortar thus mixed shall be used immediately and in no case shall the
mortar be allowed to stand for more than 30 minutes after mixing with water. The plaster shall be
laid in single coat. The mortar shall be splashed on the prepared surface with a trowel and finished
smooth by trowelling. The plastered surface shall be rubbed with iron plate till the surface shows
cement paste. The work shall be in line and level. Curing of plaster shall be started as soon as the
applied plaster has hardened enough as not to be damaged. Curing shall be done by continuously
applying in a fine spray and shall be carried out for at least 7 days.
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5.2.3 The plaster shall be carried out on jambs, lintel and sill faces top and underside, etc., as shown in
the drawing or as directed by the Engineer.

5.2.4 Cement plaster with a Floating coat of Neat Cement

The cement plaster shall be 12, 15, and 20 mm thick, finished with a floating coat of neat cement as
specified.

When the 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 rubbed smooth, so that the
whole surface is covered with neat cement coating. The quantity of cement applied for floating coat
shall be 1 Kg per sq. m. Smooth finishing shall be completed with trowel immediately and in no case
later than half an hour of adding water to the plaster mix.

5.2.5 18 mm cement plaster (two coat work)

The mix and type of fine aggregate specified in the description of the item shall be used for the
respective coats. Generally the mix of the finishing coat shall not be richer than the under coat unless
otherwise described in item.

The plaster shall be applied in two coats i.e. 12 mm under coat and then 6 mm finishing coat shall
have an average total thickness of not less than 18 mm.

12 mm undercoat: This shall be applied as specified in the schedule except that when the plaster has
been brought to a true surface a wooden straight edge and the surface shall be left rough and
furrowed 2 mm deep with a scratching tool diagonally both ways, to form key for the finishing coat.
The surface shall be kept wet till the finishing coat is applied.

6 mm finishing coat: The finishing coat be applied after the under coat has sufficiently set but not
dried and in any case within 48 hours and finished smooth.

5.3 Providing and applying Cement Paint

This may be “SNOWCEM” or of equivalent make. The surface shall be prepared as specified in the
specification for white wash. This shall be applied with brush on the plastered wall. The strokes shall
be even and it shall be cured at least for 7 days. No patch or brush stroke shall be seen. Three coats
shall be applied.

5.3.1 Providing and applying Cement paint

5.3.1.1 Material

The cement paint shall be (conforming to IS: 5410) of approved brand and manufacture. The cement
paint shall be brought to the site of work by the contractor in its original container in sealed
condition. The material shall be brought in at a time in adequate to suffix for the whole work or at
least a fortnight’s work. The materials shall be kept in the joint custody of the contractor and the
Engineer in charge.

5.3.1.2 Preparation of surface

For new work, the surface shall be thoroughly cleaned of all mortar droppings. Dirt, dust, algae,
grease and other foreign matter by brushing and washing. Pitting in plaster shall be made good and a
coat of water proof cement paint shall be applied over patches after wetting them thoroughly.

5.3.1.3 Preparation of mix

Cement paint shall be mixed in such quantities as can be used up within an hour of mixing as other
wise the mixture will set and thicken, affecting flow and finish , cement paint shall be mixed with
water in two stages. The first stage shall comprise of 2 parts of cement paint and one part of water
stirred thoroughly and allowed to stand for 5 minutes. Care shall be taken to add cement paint
gradually to the water and not vice versa. The second stage shall comprise of adding further one part
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of water to the mix and stirring thoroughly to obtain a liquid of workable and uniform consistency.
In all cases the manufacturer’s instructions shall be followed meticulously.

The lids of cement paint drums shall be kept tightly closed when not in use, as by exposure to
atmosphere the cement paint rapidly becomes air set due to its hydroscopic qualities.

In case of cement paints brought in bags, once the bag is opened, the contents should be consumed
in full on the day of its opening. If the same is not likely to be consumed in full, the balance quantity
should be transferred and preserved in an airtight container to avoid its exposure to atmosphere.

5.3.1.4 Application

The solution shall be applied on the clean and wetted surface with brushes or spraying 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 the building so that the direct heat of the sun on the surface is avoided.
The method of application of cement paint shall be as per manufacturer’s specification. The
completed surface shall be watered after the day’s work.

The second coat shall be applied after the first coat has been set for at least 24 hours. Before the
application of the second or subsequent coats, the surface of the previous coat shall not be wetted.

For new work, the surface shall be treated with three or more coats of water proof cement paint as
found necessary to get a uniform shade.

5.3.1.4 Cement primer coat

Cement primer coat is used as base coat on wall finish of cement, lime or lime cement plaster or on
asbestos cement surfaces before oil emulsion distemper paints are applied to them. The cement
primer is composed of a medium and pigments which are resistant to the alkalis present in the
cement, lime or lime cement in wall finish and provides a barrier for the protection of subsequent
coats of oil emulsion distemper paints.

Primer coat shall be preferably applied by brushing and not by spraying. Hurried priming shall be
avoided particularly on absorbent surfaces. New plaster patches in old work should also be treated
with cement primer before applying oil emulsion paints etc.

For painting with plastic emulsion paint/external water proof paint/ applying putty etc. manufactures
specifications and relevant standard specification are to be followed as directed by Engineer- in-
charge.

5.5.3.2 Providing and applying paint in wooden/steel surfaces

5.5.3.2.1Materials

Paints, oils varnishes etc. of approved brand and manufacture shall be used. Only ready mixed paint
(Exterior grade) as received from the manufacturer without any admixture shall be used. If for any
reason, thinning is necessary in case of ready mixed paint the brand of thinner recommended by the
manufacturer or as instructed by the Engineer in charge shall be used. Approved paints, oils or
varnishes shall be brought to the site of work by the contractor in their original containers in sealed
condition. The material shall be brought in at a time in adequate quantities to suffice for the whole
work or at least a fortnight’s work. Th e materials shall be kept in the joint custody of the contractor
and the Engineer in charge. The empties shall not be removed from the site of work, till the relevant
item of work has been completed and permission obtained from the Engineer in charge.

5.3.2.2 Commencing work

Painting shall not be started until the Engineer in charge has inspected the items of work to be
painted satisfied, himself about their proper quality and given his approval to commence the painting
work. Painting of external surface should not be done in adverse weather condition like hail storm or
dust storm.
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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, at least one day in
advance of the paint work being started.

5.3.2.3 Preparation of surface

The surface shall be thoroughly cleaned and dusted off. All rust, dirt, scales, smoke splashes, mortar
droppings and grease shall be thoroughly removed before painting is started. The prepared surface
shall be received the approval of the Engineer in charge after inspection before painting is
commenced.

5.3.2.4 Applications

Before pouring into smaller containers for use, the paint shall be stirred thoroughly in its containers,
when applying also; the paint shall be continuously stirred in the smaller containers so that its
consistency is kept uniform.

The painting shall be laid on evenly and smoothly by means of crossing and laying off, the latter in
the directions of the grains of wood. The crossing and laying off consists of covering the area over
the paint, brushing the surface hard for the first time over and then brushing alternately in opposite
direction, two or three times and then 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 of
crossing and laying off will constitute one coat.

Where so stipulated, the painting shall be done by spraying. Spray machine used may be (a) high
pressure (small air aperture) type, or (b) a low pressure (large air gap) type, depending on the nature
and location of work to be carried out. Skilled and experienced workman shall be employed for this
class of work. Paints used shall be brought to the required consistency by adding a suitable thinner.

Spraying should be done only when dry conditions prevail. Each coat shall be allowed to dry out
thoroughly and rubbed smooth before the next coat is applied. This should be facilitated by
thoroughly ventilation. Each coat except the last coat shall be lightly rubbed down with sand paper
or fine pumice stone and cleaned off dust before the next coat is laid.

No left over paint should 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 painted but care must
be taken to see that no paint stains etc. are left on the glass. Tops of shutters 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 of primer of approved make shall be done on the bottom edge before fixing the
shutters.

On painting steel work, special care shall be taken while painting over bolts, nuts, rivets, overlaps
etc. The additional specifications for primer and other coats of paints shall be as according to the
detailed specifications under the respective headings.

5.3.2.5 Brushes and containers

After 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 no account be used for
painting work. The containers when not in use, shall be kept closed and free from air so that paint
does not thicken and also shall be kept safe from dust. When the paint has been used, the containers
shall be washed with turpentine and wiped dry with soft clean cloth, so that they are clean and can
be used again,
 - 32 -

5.3.3 Painting priming coat on wood, iron or plastered surfaces

5.3.3.1 Primer

The primer for wood work, iron work or plastered surface shall be as specified in the description of
item.

The primer shall be ready mixed primer of approved brand and manufacture.

All the above materials shall be of approved manufacture and brought to site in their original
packing in sealed condition.

5.3.4 Painting with ready mixed paint

Ready mixed paints of approved brand and manufacture and of the required shades shall be used.
They shall conform in all respects to the relevant IS specifications.

5.3.5 Painting with plastic emulsion paint

The plastic emulsion paint is not suitable for application on external, wood and iron surface and
surface which are liable to heavy condensation. These paints are to be used on internal surfaces
except wood and steel.

Plastic emulsion paint as per IS:5411 of approved brand and manufacture and of the required shade
shall be used.

5.3.6 Painting with enamel paint

Enamel paint (conforming to IS:2932) of approved brand and manufacture and of the required
colour shall be used. For the under coat, the paint of same quality but the shade to suit that of the top
coat shall be used.

5.3.7 Painting with synthetic enamel paint

Synthetic enamel paint (conforming to IS:2932) of approved brand and manufacture and of the
required colour shall be used for the top coat and an undercoat of ordinary paint of shade to match
the top coat as recommended by the same manufacturer as far as top coat shall be used.

5.4 Providing and fixing chicken wire mesh

The wire mesh shall be of 24 gauge and it shall be fixed with nails at the junction of brick masonry
and RCC elements or as specified by the Engineer in charge. The chicken wire mesh shall not sag in
between the nails. This shall be done before the application of the plaster. It should be extended at
least 15 cm on both sides. The rate includes for carrying out the work at all heights.

6.0 FLOORING

6.1 Applicable codes

1) IS:1443- Code of practice for laying and finishing of cement concrete flooring tiles.
2) IS:2114- Code of practice for laying in situ terrazzo floor finish
3) IS: 777 – Glazed earthenware tiles.

6.2 P&L ceramic tiles in flooring, skirting and dado

6.2.1 The ceramic tiles in flooring and dado shall be of first class quality as specified in the item
specification and shall be approved by the Engineer. The tiles shall be of standard size without warp
and with straight edges, true and even in shape and size and of uniform colour. The tiles surface
shall be of fine grained texture, dense and homogeneous. The thickness of the tile shall be as per the
item specification. The tiles shall be submerged in water till the bubbles ceases.
 - 33 -

6.2.2 They shall be laid truly vertical on walls and truly horizontal on floors or to slopes as directed. The
joint shall be very thin, uniform and perfectly straight. The tiles in dado shall be finished in such a
way that, only the tile thickness projects over the finished plaster or as specified otherwise. Where
full tiles are not possible, the same should be cut or sawn to the required size and their edge rubbed
to ensure straight and true joints. After the tiles are laid extra cement grout shall be removed. The
joints shall be cleaned with wire brush and then the joint shall be floated with white or gray cement
as approved by the Engineer. The tiles shall be cleaned after the work is complete.

6.3 Vitrified Tile Flooring

The vitrified tiles shall be of approved quality, size and uniform thickness and shall be hard, sound,
dense and homogeneous in texture. It shall be uniform in shade free from stains, cracks and defects.

The dimensional variations, surface quality, physical properties and chemical properties of tiles shall
be as per internationally accepted relevant standards.

The edges are straight, with square edges and free from chippings. Tiles should be laid on a bed of
cement mortar as specified in item specifications. Thickness of mortar bedding shall be specified in
the item specifications and neat cement shall be spread over the mortar bed. The tiles shall be placed
one by one, keeping in check the level and line of flooring. Tiles are wetted before placing. The tiles
are then gently tapped with wooden mallet till it is firmly and properly bedded. There should be no
voids left. The joint should be finished with the tile joint filler of approved make and shade. The
pattern of the flooring shall be as per the architectural drawings or as directed by the Engineer in
charge.

The base concrete or the RCC slab on which the tiles are to be laid shall be cleaned, batted and
mopped. The minimum thickness of bed mortar shall not be less than 12 mm. any undulation in the
base concrete or RCC slab shall be corrected by cement mortar without any extra cost and any
additional leveling required beyond max. mortar thickness to be carried out with cement concrete.

The flooring shall be cured for a minimum period of 7 days. The surface of the flooring shall be laid
to levels and slopes as directed by the Engineer in charge.

The tiles are fixed in the floor adjoining the wall shall enter not less than 12 mm under the skirting
and dado. The junction between the wall plaster and the floor shall be finished neatly and without
waviness.

The free edges shall be cut as per the pattern and shall be polished to match with flooring.

Engineer in charge has liberty to ask for any tests with respect to physical and chemical properties,
etc. and the contractor shall arrange the same without any extra cost.

6.4 Granite Stone Flooring

The granite has to be processed by water cut method and shall be machine polished using Auto
polisher or line polisher to mirror finish to have a gloss meter reading of 90 above.

The stone shall be of approved quality, size and uniform thickness and shall be hard, sound, dense
and homogeneous in texture. It shall be uniform in shade free from stains, cracks, decay and
weathering.

The edges are machine cut to fine, straight, with square edges and free from chippings. Stone should
be laid on a bed of cement mortar as specified in the item specifications. Thickness of mortar
bedding shall be specified in the item specifications and neat cement shall be spread over the mortar
bed and the slab/tiles shall be placed one by one, keeping in check the level and line of flooring.
Tiles are wetted before placing. The tiles are then gently tapped with wooden mallet till it is firmly
and properly bedded. There should be no voids left. The joint should be paper joint. The pattern of
the flooring shall be as per the architectural drawings or as directed by the Engineer in charge.

The base concrete or the RCC slab on which the tiles are to be laid shall be cleaned, batted and
mopped. The minimum thickness of bed mortar shall not be less than 12 mm. Any undulation in the
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base concrete or RCC slab shall be corrected by cement mortar without any extra cost and additional
leveling required beyond maximum mortar thickness is to be carried out with cement concrete.

The flooring shall be cured for a minimum period of 7 days. The surface of the flooring shall be laid
to levels and slopes as directed by the Engineer in charge.

Due care shall be taken to match the grains of tiles which shall be selected judiciously having
uniform pattern.

The tiles which are fixed in the floor adjoining the wall shall enter not less than 12 mm under the
skirting or dado. The junction between the wall plaster and the floor shall be finished neatly and
without waviness.

The free edges shall be cut as per the pattern and shall be polished to match with the flooring.

Before starting the work, the contractor shall generally get samples of granite tiles polished to the
satisfactory level for approval of Engineer in charge and shall be kept in the custody of the Engineer
in charge and the tiles/slabs supplied and used on the work shall confirm to the samples with regard
to soundness, colour, shades, general texture and finishing/polishing.

Engineer in charge has liberty to ask for any tests with respect to physical properties, levels of
polishing, etc. and the contractor shall arrange the same without any extra cost.