Question

When the concrete in fresh stage is exposed to freeze before certain pre-hardening period, compressive strength may get __________

(a) Increased to 50%

(b) Decreased to 50%

(c) Increased to 25%

(d) Decreased to 25%

The question was posed to me during an interview.

I'm obligated to ask this question of Factors Affecting PIC, Cold Weather Concreting topic in chapter Special Concrete and Concreting Methods of Concrete Technology

Answer 1

The correct option is (b) Decreased to 50%

To explain: When the concrete in fresh stage is exposed to freeze before a certain prehardening period, concrete may suffer loss in its prop. to an extent that compressive strength may get decreased to 50%.