Long term study of hardened cement pastes containing silica fume and fly ash

The hydration products in cements with individual addition of SF and two types of FA from TEPS and mixtures of FA and SF are studied. The phase transformations are followed in a 4-year period. Fly ashes from TEPS “Bobov Dol” and TEPS “Pernik”, silica fume from the metallurgical plant “Kremikovtsi”, and their mixed product Pozzolit are suitable pozzolanic additions to cement as they participate actively in the processes of formation of hardened cement paste. The above additives stimulate the formation of hydrate products with temperature of dehydration above 600 °С, more clearly expressed after the 48th day of hydration.