The effect of damp sand content on the geopolymerization reaction of fly ash-based geopolymer mortars

Abstract

The results of the current experimental investigation indicates the significant effect of the natural sand content prepared in damp condition on the compressive strength of fly ash-based geopolymer mortars prepared at different alkaline liquid content. The results show that applying Sand: FA ratios above 1.5:1.0 extremely deteriorate the geopolymerization process producing a geopolymer mortar without any reported strength. The lowest damp sand content at mass ratio of Sand: FA= 0.5:1.0, possess the minimum strength loss percent of 41, 55 and 37 % with respect to each Activator/FA ratios 0.3, 0.35, and 0.4. The trend of strength loss with increasing the damp sand content was strongly correlated with the nature of the geopolymerization complicated reaction and its dependency on the water content. The reported strength continued to decrease with increasing the water content which resulting from increasing the damp sand content.