Pengaruh Variasi Konsentrasi NaOH Sebagai Alkali Aktivator Terhadap Kuat Tekan Semen Geopolimer Berbasis Tanah Napa

Abstract

— In 1970, Davidovits discovered an alternative binder called geopolymer. Geopolymer is a material or binder material synthesized by mixing alumina silicate source material and alkaline activator solution. One of them is Napa land. Napa soil contains high levels of SiO2 and Al2O3 with percentages of 62.70% and 31.16% based on the XRF test. NaOH solution mixed with Na2SiO3 was used as an activator whose concentration varied from 8M to 14M. The ratio of the weight of Na2SiO3 to the importance of the NaOH solution is 1.5. The characteristics of the geopolymer cement based on napa soil showed that the analysis of optimum compressive strength was achieved at a concentration of 14M. Compressive strength tests of cylindrical specimens, splitting tests, and porosity tests were carried out comprehensively to compare the samples from each composition. The higher the concentration of NaOH, the higher the compressive strength produced.