Effect of curing condition on the performance of geopolymer-based reactive powder concrete

The focus of this study was on formulating geopolymer-based reactive powder concrete (RPGC) utilising ground granulated blast-furnace slag (GGBFS) and fly ash (FA) as precursors. The primary objective was to evaluate the mechanical performance of RPGC under different curing conditions (50% relative humidity (RH), 80% RH and immersion in lime-saturated water) at a constant temperature of 23±2°C. Two groups of RPGC mixes with distinct precursors were prepared. Each group contained mixes with three different liquid ratios, representing the ratio between the volume of the activator and the volume of all solid ingredients, subjected to three different curing conditions. The mechanical performance of the RPGC was evaluated through tests for the apparent volume of permeable voids (AVPV), compressive strength and flexural strength. The results of this work highlight the considerable influences of curing condition on the RPGC. The minimum AVPV was observed for curing at 80% RH, followed by water immersion curing and curing at 50% RH. The highest compressive strength of the RPGC was achieved for curing at 80% RH, followed by water immersion curing and curing at 50% RH. The highest flexural strength of RPGC was also achieved for curing at 80% RH.