Question

The two main compounds of Ordinary Portland Cement are

• A. Tricalcium Silicate and Dicalcium Silicate
• B. Dicalcium Silicate and Alkali Oxide
• C. Tricalcium Aluminates and Alkali Oxide
• D. Tricalcium Silicate and Alkali Oxide

Answer 1

The correct option is A Tricalcium Silicate and Dicalcium Silicate

$C_{3}Sand{C}_{2}S$ which together constitute about 70 to 80% of the cement control most of the strength giving properties. $C_{3}S$ giving a faster rate of reaction accompanied by greater heat evolution develops early strength. $C_{2}S$ Hydrates and hardens slowly and provides much of the ultimate strength.