Question

In Bouge compounds, the main characteristics role of C₂S is:
1. high heat of hydration
2. low heat of hydration
3. initial setting of cement
4. final setting of cement
5. early strength development

Answer 1

Correct Answer - Option 2 : low heat of hydration

Concept

There are four compounds (Called Bogue's Compounds) formed as a result of hydration of cement:

Alite: C3S, or Tricalcium Silicate

Belite: C2S, or Dicalcium Silicate

Aluminate phase: C3A, or Tricalcium Aluminate

Ferrite phase: C4AF, or Tetracalcium Aluminoferrite

Bogue Compounds

Dicalcium Silicate (C2S): This compound will undergo reaction slowly. It is responsible for the progressive strength of concrete. This is also called as Belite. 

A higher percentage of C2S results in slow hardening, less heat of hydration, and great resistance to chemical attack.

The heat of hydration is 260 J/Cal.