Question

What are the roles of C3A and C4AF in cement hydration?

Answer 1

C₃A

It is having the fastest rate of a chemical reaction and it also has a very high heat of hydration near about 865j/gm.

responsible for flash set property.

this bouges compound is responsible for the flash set property in the clinker. it is the compound which reacts with water immediately when is added to the cement.

this is the most unstable compound in comparison to the other bouges compound this compound offers resistance to freezing and thawing, a very high percentage of C3A in cement causes cracking of the structure.

this compound contribute in 24hr strength. during hydration of cement

C₄AF

is contribution in strength is very less.

heat of hydration is near about 420 j/gm

itis responsible for high heat of hydration as compared to C₂S but less than C3A

it is having contribution within 24hr of adding water to cement.