Investigation of fire resistance of glass powder doped and blast furnace slag based geopolymer concrete

The aim of this study is to investigate the effect of glass powder on the fire resistance of blast furnace slag based geopolymer concrete. 5 groups of geopolymer concrete were produced by using 0%, 5%, 10%, 15% and 20% glass powder instead of blast furnace slag (GGBFS) and activated with NaOH. Compressive strength, splitting tensile strength and capillary permeability tests were performed on the control samples. After a 28-day curing period, air and water cooling was applied to samples exposed to temperatures of 150, 300, 450, 600 and 750°C. Then, compressive strength, fire resistance, capillary permeability and weight loss tests were performed on these samples. Considering the test results, the addition of glass powder to geopolymer concrete samples at room temperature decreased the compressive strength. Higher strength was obtained from the samples cooled in air after high temperature compared to the samples cooled in water. The capillary permeability coefficient and weight loss increased with increasing temperature. As a result of visual inspection, it was observed that the amount of voids increased with the increase of glass powder in the samples exposed to high temperature. The obtained data were supported by microstructural analysis. Keywords: Geopolymer concrete, blast furnace slag, glass powder, fire resistance.