Question

A Ready-mix concrete supplier supplied 101 cum of concrete for a slab. As per the minimum sampling frequency, the number of cube samples required are
1. 5
2. 4
3. 7
4. 6
5. 3

Answer 1

Correct Answer - Option 1 : 5

Explanation:

As per CI. 15.2.2 of IS 456:2000 The minimum frequency of sampling of concrete of each grade shall be in accordance with the following:

Quantity of concrete in work (m3)	Number of samples
0 - 5	1
6 - 15	2
16 - 30	3
31 - 50	4
51 and above	4 plus one additional samples for each 50 m3 or part thereof

At least one sample shall be taken from each shift. Where concrete is produced continuously (e.g. in RMC plants), there, frequency of sampling may be agreed upon mutually by the supplier and the buyer.