It is an intimately inter-ground mixture of Portland clinker and sly ash with the possible addition of gypsum or an intimate and uniform blending of Portland cement and fly ash. Fly ash used in manufacture of Portland-pozzolana cement should confirm to IS:3812(part 1)-2003.In this type of cement, the fly ash constituent shell not less than 15% and not more then 35% by mass of Portland-pozzolana cement.
Percentage of Production in Portland-pozzolana cement (Fly ash based) In India has steadily increased from 17.31% in 1989-90, to 60.12% in 2006-07 and to 67% in 2010-11.
Portland-pozzolana cement (Fly ash based) produces less heat of hydration and offers greater resistance to the attack of aggressive waters than Ordinary Portland Cement.
In this type of cement particularity useful in marine and hydraulic Construction and other mass concrete structures.