Factors affecting the strength of alkali-activated slag

The effect of several factors on the strength of alkali activated slags has been investigated. The most important factors were found to be: the type of alkaline activator, the means of adding activator, the dosage of alkali, the type and fineness of slag, SiO2/Na2O ratio (modulus, Ms) when using waterglass solution, curing temperature, liquid/slag or water/slag ratio and additive. Some of these factors are interdependent and the effect of changing more than one is usually not additive. The optimum range for each factor is suggested through reviewing previous work and our recent results of a full factorial range strength study. The interaction of factors is considered and discussed throughout the paper, hoping to gain a better understanding of the processing of alkali-activated slag (AAS) cement and concrete.