Bricks MCQ with answer and solution

Concept

Water absorption limit for first class brick

Formula

NONE

Step-by-step solution

1. Water absorption tests assess the quality and durability of bricks. 2. According to standard specifications, a first-class brick should not absorb water more than 20% of its dry weight when immersed for 24 hours. 3. Expressed as a fraction of dry weight, 20% corresponds to 0.2. Answer: C

Explanation

Standard engineering specifications for building materials require that a first-class brick absorb no more than 20 percent (or 0.2) of its dry weight in water when immersed for 24 hours. A low water absorption limit ensures high durability, strength, and resistance to weathering forces. Exceeding this limit indicates higher porosity and lower structural quality.

Why the other options are wrong

A) Water absorption of 10% is significantly below the maximum permissible limit for 1st class bricks. B) Water absorption of 15% is the maximum permissible limit for 2nd class bricks. D) Water absorption of 25% is the maximum permissible limit for 3rd class bricks.

Shortcut

1st class brick maximum water absorption is 20% (0.20) of dry weight.

Common mistake

Confusing the maximum water absorption limit of 20% for 1st class bricks with 22% or 25% for lower classes.