A. Allahverdi, E. Najafi Kani, S. Esmaeilpoor,
Volume 5, Issue 2 (6-2008)
Abstract
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 28-day compressive strength
and final setting time, were studied by changing influencing parameters such as silica modulus,
i.e. SiO2/Na2O, (0.44, 0.52, 0.60, and 0.68) and Na2O concentration (4, 6, 8 and 10% by weight of
dry binder) at a constant water-to-dry binder ratio of 0.25. Final setting time of the studied
systems varies in the range between 55-386 minutes. The obtained results show that systems cured
at an atmosphere of more than 95% relative humidity at room temperature exhibit relatively high
28-day compressive strengths up to 107 MPa.
