Effect of Activator Solution Molarity on the Performance of Perlite-Substituted Geopolymer Concrete

Cement contributes CO 2 emissions to the atmosphere, which is harmful for human health. Several researchers have conducted experiments to find materials that have the potential to be used as cement substitutes. Fly ash and perlite are wastes that contain silica as well as high aluminum, so they have potential as cement replacement materials. In this study, geopolymer concrete mixtures were made using fly ash and perlite with a NaOH concentration of 10M – 16 M, a Na 2 SiO 3 /NaOH ratio of 2.5 and alkaline solution to fly ash ratio (AA/FA) of 0.5. The curing method used was using an oven at 80 °C for 16 hours. From the experimental results, the optimum compressive strength was 28.470 MPa with a 12M NaOH concentration. The optimum flexural strength was 2.387 MPa with a NaOH concentration of 12M.