Question

In Portland cement the strength after two to three years is contributed by the compound

• A. Tetracalcium aluminoferrite
• B. Di-calcium silicate
• C. Tricalcium silicate
• D. Tricalcium aluminate

Answer 1

The correct option is B Di-calcium silicate

Ans (b) : In Portland cement , the strength after two to three years is contributed by the compound Dicalcium silicate.
Di-calcium silicate $\left(C_{2}S\right)(25-40\%)$;-

• It hydrates slowly and takes long time to add to the strength (after a year or more)
• It is responsible for ultimate strength.
• It imparts resistance to chemical attack.