Blast-furnace slag-based geopolymer concretes: The effect of glass powder on sulfate resistance

In this study, research has been conducted on the durability of geopolymers against sulfate effects. Within the scope of the research, geopolymer concretes were produced using blast furnace slag (YFS) and glass powder as binders. Six different groups were created, and glass powder was added in weights of 0%, 10%, 20%, 30%, 40%, and 50% instead of YFS. Geopolymer concrete samples were exposed to 3% concentrations of magnesium sulfate and sodium sulfate solutions for 12 weeks after completing the 28-day curing period. During the study, changes in compressive strengths, flexural strengths, capillary permeability, weight, and pH values of the samples were monitored, and visual changes were examined. The experimental results were evaluated by comparing them with the results of the control samples cured for 28 days in a laboratory environment. According to the findings, the highest compressive and flexural strengths of geopolymers were obtained in the C0 group with a 0% glass powder ratio. An decrease in compressive and flexural strength values was observed as the glass powder ratio increased. Samples immersed in sulfate solutions showed a decrease in compressive and flexural strength values, while capillary permeability coefficients increased. Visual examination revealed no deterioration in samples immersed in sulfate solutions.. Keywords: Geopolymer concrete, blast furnace slag, glass powder, sulfate resistance