Civil Engineering - Building Materials - Discussion

The good quality of cement contains;

50% of tricalcium silicate- for rapid strength and quick setting of cement.
30% of dicalcium silicate- hardens slowly and responsible for long term strength.
10% of tricalcium aluminate-quick action with water.
10% of tetra calcium Aluminoferrate.
5% of Gypsum.

I think the given answer is correct.

C3S 45-65.
C2S 15-35.
C4AF 10-18.
C3A 4-14.

Ref: RANGWAALA BOOK.

It should be tricalcium silicate.

Option A is correct because the question was about an overall higher percentage. So as calculated,
1) Tricalcium silicate is 30-50%.
2) Di-calcium silicate is 20-45%.
3) Tri-calcium aluminate is 8-12%.
4) Tetra calcium alumino ferrite is 6-10%.

The answer is correct A.

Because of an excess of C3A early strength and save from sulfur attack.

Correct Answer is- C2S.

During Reaction C3S & C2S:- C-S-H & Ca (OH) 2 formed, CSH is the good properties of conc. Makes up 50-60% vol. Solid.

And that reactions seen C3S produces lesser quantity C-S-H and more quantity Ca (OH) 2 and that is not desirable product in concrete mass it is soluble in water makes conc. Porous, and also the quality density of C-S-H formed out C3S is slightly inferior to that form by C2S.

Ref: M S SHETTY.

Option A is correct. C3S higher percentage used.

C3S - Early strength.
C2S - Ultimate strength.
So the given answer is correct.