Question

Cement and water when poured into the form work for hardening normally takes ________ days to acquire fixed properties.
1. 7
2. 14
3. 21
4. 28

Answer 1

Correct Answer - Option 4 : 28

Explanation:

The degree of hydration is synonymous with the age of concrete provided the concrete has not been allowed to dry out or the temperature is too low.

It is seen that majority of strength gain by concrete is achieved in 28 days and the rest is continuous throughout the life of the concrete.

Concrete mainly gains strength by hydration of water present in it, this will lead to a decrease in water-cement ratio and increase in strength of concrete.

Therefore, the Strength of concrete increases with age.