Question

In handling air-entraining admixtures the beneficial amount of entrained air depends upon certain factors like
1. Type and quantity of air-entraining agent
2. Water-cement ratio of the mix
3. Strength of aggregates
4. Extent of compaction of concrete

• A. 1, 2 and 3 only
• B. 1, 2 and 4 only
• C. 1, 3 and 4 only
• D. 1, 2, 3 and 4

Answer 1

The correct option is B 1, 2 and 4 only

The beneficial amount of entrained air depends on the workability requirement of the concrete mix.
Air-entraining admixture causes small stable bubbles of air to form uniformly through a concrete mix.
Entrained air depends upon certain factors like

• Type and grading of aggregate.
• Influence of compaction.
• Type of cement.
• Mixing time and temperature
• Water cement ratio of the mix.

The strength of aggregates does not have any bearing on the workability of concrete.