Question { Nagarjuna Construction, 16815 }

what is the meaning for 'prime cost' in civil construction
contracts?

Answer

While working out the abstract for a job, it is not always
possible to define everything necessary for the completion
of the building. For example, certain items such as water-
supply fittings, plumbing fixtures, etc, are to be decided
by the Architect, later on. Hence it is not possible to
work out the cost of such items at the time of inviting
tenders. So a lumpsum provision is made for these items. It
is called PRIME COST Provision, and is subject to
adjustment against actual items selected later.

Question { L&T, 30812 }

Is 456 revised lastly in which year? & What are the revisions?

Answer

IS 456 is revised on 1978. i dont know the changes exactly.
but in the old IS 456(1964) the unit was KG/SQ.CM.
that means compressive strength is mentioned as
100kg/Sq.cm, after the revision it is mentioned as N/sq.mm

Question { 21622 }

how to consider the lap length of a bar in IS code and
specify the code book name and clause& page number?

Answer

Lap Splices :
Lap Splices shall not be used for bars larger than 36mm
dia. For larger diameters, bars may be welded. In case
welding is not practicable, lapping of bars larger than
36mm may be permitted, in which case additional spirals
should be provided around the lapped bars.

Lap Length in Tension : lap length including anchorage
value of hooks in flexural tension shall be Ld or 30D
whicever is greater and for direct tension 2Ld or 30D
whichever is greater. The straight length of lap shall not
be less than 200mm, whicever is greater.
*Ld - Development Length

Lap Length in Compression : The lap length in compression
shall be equal to the development length in compression
calculated. But shall not be less than 24D

Bars of Different Diameter : When bars of wo different
diameters are to be spliced, the lap length shall be
calculated on the basis of diameter of the smaller bar.

SOURCE : SP34 Hand Book on Concrete Reinforcing and
Detailing --- Clause 4.4.2 lap splices.

Question { 21654 }

Q:What is the formula of bar to bent the slab in bent slab?
Second question Q: what is formula to calculate the hook?

Answer

one Hook length is equal to 9D. .

Question { 53360 }

what is the specification for silt content in sand

Answer

SILT Content in Sand should not be more than 7% by Volume.
( means upto 7% can be used without Washing).

Silt content of a Sand is meaured by folllowing
Procedure,
a) Take a clean 200ml. measuring jar
b) Fill with sand upto a certain mark ( say reading 'X')
and add water above it upto 200ml. and shake well.
c) Allow a period of 2hours for settlement
d) Clean sand will settle at the bottom with silt and clay
impurities on top of the sand layer.
e) Now oserve the top level reading for sand. Assume that
is 'Y'. Then the silt contain in % is given by,
% Silt content = (X-Y/X)*100

Question { Jaypee, 68996 }

What"s mean by term of BOQ in construction?

Answer

BOQ means "Bill of Quantities".
Actually the BOQ is submitted by the Design Consultant to
the Contractor. Contractor has to quote the rates for each
items in the BOQ. Then finally the contractor who has
quoted the nominal rate will be selected for the particular
work.

Question { 10379 }

what should be the deduction for bend in stirrups while
calculating cutting length? Is it 1 dia at each bend?

Answer

There is no deduction for bends. We shall add the
additional bend lengthts on both sides.
For 30degree bend, the additional length at one side is 0.3D
For 45degree bend, the additional length at one side is 0.4D
and the hook length would be 18D for both sides.

Question { L&T, 20131 }

What is the significance of Hook's in stirrups.

Answer

Hooks provided for Bond between Concrete and steel. It
prevent slippage of steel from the concrete.
But remember, Hooks are used in Plain Bars only. In case of
Ribbed Bar(Twisted), Hooks are useless. as the Twisted Lug
and Deformations satisfying the bondage, the hooks are
unneceary and not adopted.