The specific surface of cement is a property cement used to know the ______.

Concept:

• Specific surface is expressed as the total surface area in square meters of all the cement particles in one kilogram of cement.
• The fineness of cement is measured as a specific surface.
• The higher the specific surface is, the finer cement will be.

Method of testing fineness of cement:

a) Sieve Analysis Method

b) Air Permeability Method

For ordinary Portland cement:

• The residue present in OPC cement should not exceed 10 % by the dry weight of cement.
• The specific surface of this type of cement should not be less than 2250 cm2/gm.

For rapid hardening cement:

• The residue present in this rapid hardening cement should not exceed 5 % by the dry weight of cement.
• The specific surface of this type of cement should not be less than 3250 cm2/gm.

For Portland Pozzolana Cement:

• The residue present in PPC cement should not exceed 5 % by the dry weight of cement.
• The specific surface of this type of cement should not be less than 3000 cm2/gm.