Hydration of which of the following compound(s) will result in the increase of strength of the concrete after 28 days? i. Di-calcium Silicate ii. Tri-calcium Silicate iii. Tri-calcium Aluminate iv. Tetra-calcium Aluminoferrite
- AOnly (i)Correct
- B(i) and (ii)
- C(i) and (iii)
- D(iii) and (iv)
Solution
Concept
Strength gain after 28 days
Step-by-step solution
1. C₃S hydrates quickly and gives early strength. 2. C₂S hydrates slowly, so it gives the later strength after 28 days.
Explanation
Dicalcium silicate is responsible for long-term strength.
Why the other options are wrong
C₃S, C₃A and C₄AF act mainly in the early period.
Shortcut
C₂S = later strength.
Correct answer: A) Only (i)