Question

How to calculate volume of gel pores in cement paste?

Answer 1

In pyknometry, total gel volume of the cement paste is given by the equation

Vgel= Vc·α·c + Vw·Wn +0.28·Vgel

Where,

α is the degree of hydration

c is weight of cement

Wn is weight of chemically bound water

Vc is the specific volume of cement = 0.32 cm3 /g

Vw is the specific volume of chemically bound water = 0.75 cm3 /g).

Therefore, Vgel=(0.32·α·c +0.75·0.25·α·c)/0.72 = 0.705·α·c

Volume of gel pore Vgel-pore is 28% of volume of gel.

Vgel-pore =0.28 * 0.705·α·c

Formula to calculate volume of gel pore in cement paste is Vgel-pore = 0.197·α·c