EFFECTS OF SILICA MODULUS AND ALKALI CONCENTRATION ON ACTIVATION OF BLAST-FURNACE SLAG

Abstract: The use of alkali-activated cementitious materials especially over the past decades has significantly been increased. The goal of this research is to investigate the effects of silica modulus and alkali concentration on alkali-activation of blast-furnace slag. In this research, the most important physical characteristics of cementitious systems, i.e. the ۲۸-day compressive strength and final setting time, were studied by changing influencing parameters such as silica modulus, i.e. SiO۲/Na۲O, (۰.۴۴, ۰.۵۲, ۰.۶۰, and ۰.۶۸) and Na۲O concentration (۴, ۶, ۸ and ۱۰% by weight of dry binder) at a constant water-to-dry binder ratio of ۰.۲۵. Final setting time of the studied systems varies in the range between ۵۵-۳۸۶ minutes. The obtained results show that systems cured at an atmosphere of more than ۹۵% relative humidity at room temperature exhibit relatively high ۲۸-day compressive strengths up to ۱۰۷ MPa.

کلیدواژه ها:

Alkali-activation ، Blast-furnace Slag ، Setting Time ، Compressive Strength.