Civil Engineering — MCQ Practice Questions & Answers

Question 1

Which chemical compound in cement causes flash setting when exposed to water?

Accepted Answer

Correct answer: C. C3A (Tricalcium Aluminate) — C3A reacts rapidly with water and is responsible for flash setting. Gypsum is added to control this reaction.

Answer

A. C3S (Tricalcium Silicate)

Answer

B. C2S (Dicalcium Silicate)

Answer

D. C4AF (Tetracalcium Aluminoferrite)

Question 2

According to Abrams' Law, the relationship between w/c ratio and compressive strength is:

Accepted Answer

Correct answer: B. Inverse/Negative exponential relationship — Abrams' Law states that compressive strength decreases exponentially with increase in water-cement ratio.

Answer

A. Linear positive relationship

Answer

C. No relationship

Answer

D. Directly proportional

Question 3

Self-compacting concrete (SCC) must achieve a slump flow of:

Accepted Answer

Correct answer: C. 600-800 mm — SCC requires slump flow between 600-800 mm to flow and compact under its own weight without vibration.

Answer

A. 150-250 mm

Answer

B. 300-500 mm

Answer

D. 900-1000 mm

Civil Engineering - MCQ Practice Questions