Question

Equation for cement requirement in tones for four-story R.C.C. framed building (super structure) recommended by C.B.R.I is
1. 0.153 A + 0.57
2. 0.145 A + 0.54
3. 0.182 A – 0.35
4. 2.26 A + 66.8

Answer 1

Correct Answer - Option 3 : 0.182 A – 0.35

Concept:

• CBRI has recommended the following formulae which after a study of the specifications have been selected for this analysis.
• The table as given below is for buildings of different shapes and plinth areas varying from 30 to 300 sq. these are the average constant.

 

Materials	Equations	Labours (in days)	Equations
Cement(tones)	0.0204A- 0.014	Mason	0.023A
Sand (cu.m.)	0.036A	Carpenter	0.05A
Coarse aggregate (cu.m.)	0.071A-0.01	Blacksmith	-1.6+0.1A-0.0003A2
Steel (kg)	-171+10.46A-0.041A2	Mazdoor	0.343A

Where, A = Plinth area in sq.

Option 3 is close to the given equation by CBRI for cement. Hence, option 3 is correct.

• This information is useful for the preparation of the building cost index, preplanning of materials, and labour requirement in a building project. Equations for Materials & Labour requirement for structure in Four-storeyed (RCC Frames Building),