Question { Jaypee, 8680 }

how much % of fine sand(jamuna sand)we can use with coase
sand for making concrete.

Answer

If you use this sand or any other sand first you go
to sieve anaylisis & check finess mould as per IS
CODE.
Then use % sand as per nominial mix m20 or m25
or design mix

Question { Earthcon, 45403 }

what is the spacing required for chairs for reinforcing in
raft footing.

Answer

As per IS 456:2000, the maximum spacing chair is
1m and closer may spacing as per recquired

Question { L&T, 29723 }

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

Answer

yes it is revised to IS 456:2000
basic M15 grade is omitted and minimum concrete grade is
M20

Question { HSCC, 96485 }

What is meant by Anchorage length? Development Length?

Answer

Development length is the length overlap of bars tied to
extend the reinforcement length. is about 50 times the dia
of bar is consider to safe.

Anchorage length- this is the additional length of bar
recquired ti insert in another at the junction. For example-
Main bar of the beam in column at beam column junction.
this length is simiilar to the lap length.

Question { 5703 }

Q1) I am having an interview in a construction company for
a large sewage project . Since I have not done any such
project , there are some queries from my end. Pls. help me
to solve them. I will be thankful to you :-

a) Normally for large project 400-600 houses & around
1600 peoples , how much dia pipe is used and which type of
pipe is used?
b) For trenching , I have heard that IS 1200 implies,
what are the rules of calculating earthwork in case of
depth of 2m or above ?
c) To prevent soil to fall when depth of trench is
more , what steps are taken and how there qty. is
calculated . Like I have heard about timbering . what is
this ?
d) What are the rules for disposing off the excavated
soil ?
e) How the pipes that are used are being jointed?
f) In case of cleaning on choks , is there any
intermediate things provided?
g) For foul gases any outlets are provided thru out
length of pipeline?
h) What is the flow digram like from houses thru small
pipe to main pipeline than where main pipeline disposes
wastage ?
i) Any other thing that has to be kept in mind while
calculating earth work for excavation like steps are made
and other things? How earthwork is calculated in case of
steps ? Pls. explain with a sketch.


Regards,

Answer

Ans1. +generally raw water from house to treatment plant CI
pipe are used. is maximum 600 Dia. in plant maximum 200 dia
re used. HDPE pipe are used.

ans - calculating earthwork is based on site condition.
although some rules are provided in IS 1200, but it is
better to calculate in site. below 2mm avg. calculation are
done

ans-for falling of earth scour are applied. this means some
protection done for sliding soil to the trench. it is aform
of net, tina fixing or sand bags are provided.

Ans- disposal of earth from site not follow some basic
rule. Calculate filling earth. volume of this earth are
store in suitable site. rest you disposal according site
incharge.

ans- pipes are joint in collar joints or welding

ans- choks are omitted by manual or by pressure

ans- no vent pipre are not provided in pipe. sweage dirctly
transfer to treatment plant. air ventilation pipe are
provided for air pressure.

ans- sorry this page are not allow to draw sketch

Question { 4225 }

indiploma civil engineering student r studied is456-1978.

but in practicial we r using 2000 version
i think 1978 version didn't use the student.

any openion?

Answer

No, although some changes are done in 2000 version, but
desigin criteria is same.
example- M20 grade concrete takes place instead of M15 for
general concrete. but proportion are same

Question { 2977 }

A floor has to be removed partially with block work tying
floors together, can block work continue on floor that has
to removed excluding demolishing works tying floor from
underside of slab and top of slab demolishing floor upon
completion?

Answer

what is block working. if it is brick working or what.
if you want demolishing then you give support for others.

Question { 6764 }

1. if only 1 slab of a floor get sagged, how could be it
repaired?
2. if any footing gives the cube result, after 28 days less
than 16 n/mm2 in spite of 20 n/mm2 what are the remedies ?

Answer

look if slab get sagged it better to be dismentaling and
construct new slab. by constructing new slab other floors
will not affect, because load carried by column.

your second question if cube result are below their
strength, as per is code it will better to be dismentaling.

Question { L&T, 19398 }

RCC colums of 15"X9" each, roof height 10.5'ft, total
pillars 12 nons. Span between pillar to pillar is 14/20/20
length wise and 17/14 width wise. Total Slab area 2400 sft
and plinth area is 1900 sft. beams are 12"X12". kindly
calculate load factor per sqft.

Answer

calculating load factor
incase of astructure some live load and dead load is
calculating
As per IS code - take live load-4.0 kn/Sqm
terrace finish- 1.5 kn/sqm
floor finish - 1.0kn/sqm
water proofing- 2.0 kn/sqm
----------------------------
total load-8.5 kn/sqm
i conver all ft ad inch to mt and mm
dead load of column or its own weight-
.38x.228x25x12=25.992kn/m 25kn/m recc wight
beam weight- .304x.304x25x15.732x3=109.041
- .304x.304x25x29.5x4=272.62
slab weght- 222.22x.100x25= 555
------------------------------------------------------
total weight= 962.653kn/sqm

total dead load+ live load=962.653+8.5 = 971.153kn/sqm
so per sqm load factor = 971.153 kn /sqm
you can easily convert it per sqft

Question { bscpl, 8020 }

for rcc which condition will u adopt now

Answer

i donot understand your question. As i think the answer
your question is M20 garde of rcc we are used now a days.

Question { L&T, 27188 }

What is the diffence between prescribed mix and design mix

Answer

Prescribed mix is some mixing proportion given by IS 456-
2000 for diffrent type of grade of concrete. example- M20
is 1:11/2:3
design mix is consider from local material to achieve
strength of respective grade of concrete.

Question { 9100 }

Difference between the setting time and hardenin time of
concrete

Answer

setting time is taken by concrete to its minimum strength
in 7 days. harden time is time taken by concrete to its
maximum strength.

Question { 14615 }

Define slump in terms of slump test

Answer

slump is the term oe water cement ratio in concrete.there
is diffrent slump in diffrent concrete.

Question { 11471 }

What are the types of test used to determine soil bearing
capacity

Answer

1. penotrometer test
2.plate load test
3. field density test

Question { Ramky, 17388 }

What is Bearing Capacity of Soil? How will you calculate
for a particular type of Soil?

Answer

In geotechnical engineering, bearing capacity is the
capacity of soil to support the loads applied to the
ground. The bearing capacity of soil is the maximum average
contact pressure between the foundation and the soil which
should not produce shear failure in the soil. Ultimate
bearing capacity is the theoretical maximum pressure which
can be supported without failure; allowable bearing
capacity is the ultimate bearing capacity divided by a
factor of safety