Question

the pillars of a temple are cylindrically shaped. if each pillar has a circular base of radius 20 cm and hight 7m then fond the quanity of concrete mixture used to build 20 such pillar also find cost of concreat mixture at the rate of rs.200 per m^π=22/7​

Answer 1

Answer:

As we know that during concreting when we place wet concrete , it gets harden after certain standard time( 30 mins IST & 10hrs FST), considering same it had be decided upon by Civil design Engineers to take a factor of safety ranging from 1.54 to 1.57 to counter that shrinkage.

i.e volume of dry Concrete = 1.54 to 1.57 times Volume of wet concrete.

Now calculations is as follows for 1cum(assumed) of Concrete work

ratio Sum = 1+1.5+3=5.5

Shrinkage or safety Factor =1.57 (you can take 1.54 also)

So Total volume of wet concrete required is :- 1.57cum

Volume of broken stone Require = (3/5.5) x 1.57 = 0.856 m3

Volume of sand Require = (1.5/5.5) x 1.57 = 0.471 m3

Volume of cement = (1/5.5) x 1.57 = 0.285 m3

= 0.285 x1440 = 411 kg

For 1m3 of M20 (1:1.5:3)

Broken stone = 0.856 m3

Sand = 0.472 m3

Cement = 8.22 bag.

Some important conclusion from above

8 bag of Cement is required for 1cum of concrete work in M20.

4.4 bag of cement is required for 1cum of concrete work in M10.

volume of dry concrete =1.54 times volume of wet concrete.

Thank You Folks!