Question

As per IS 456, the minimum cement content for the respective durability classes can be reduced by R kg/cum while changing the maximum size of aggregate from 20 mm to 40 mm, wherein R is
1. 10
2. 15
3. 20
4. 25
5. 30

Answer 1

Correct Answer - Option 5 : 30

Explanation:

As per IS 456:2000 Adjustments to Minimum Cement Contents for aggregates Other Than 20 mm Nominal Maximum Size:

Nominal Maximum aggregate Size	Adjustments to Minimum Cement Contents
10 mm	+ 40
20 mm	0
40 mm	- 30