Question

Match all the possible combinations between Column X (Cement compounds) and Column Y (Cement properties):

Which one of the following combinations is correct?

• A. (i) - (P), (ii) - (Q) and (T), (iii) - (R) and (S)
• B. (i) - (Q) and (T), (ii) - (P) and (S), (iii) - (R)
• C. (i) - (P), (ii) - (Q) and (R), (iii) - (T)
• D. (i) - (T), (ii) - (S), (iii) - (P) and (Q)

Hint:

Cement compounds like C$_3$S and C$_3$A contribute significantly to early strength and heat generation, while C$_2$S is mainly responsible for later strength.

Answer 1

The Correct Option is A

- C$_3$S (Tricalcium silicate) contributes to early age strength (P) and gives the highest heat of hydration (S), as it reacts quickly with water.
- C$_2$S (Dicalcium silicate) is responsible for later age strength (Q) and has the lowest heat of hydration (T), as it hydrates more slowly than C$_3$S.
- C$_3$A (Tricalcium aluminate) causes flash setting (R) and contributes to high heat of hydration (S) because it reacts rapidly with water.
Thus, the correct combination is:
\[ \boxed{\text{(A) (i) - (P), (ii) - (Q) and (T), (iii) - (R) and (S)}}. \]