Use Recycled Glass As Fine Aggregate in Slag-Blended Fly Ash-Based Geopolymer Mortar

Abstract

Geopolymer has emerged as the potential alternative to Portland cement in recent years. In addition, fly ash and recycled glass are abundant by-products derived from the industry. The purpose of this study was to evaluate the potential of using recycled glass to replace the sand aggregate in slag-blended fly ash-based geopolymer mortar. For geopolymer synthesis, the mixture of water glass (Na2SiO3) and sodium hydroxide (NaOH) solution with a NaOH concentration of 14 mol/l was used as an activator. In the mortar mixture, the recycled glass's investigated replacement level of the sand aggregate was up to 100 %. Using recycled glass (RG) as fine aggregate was seen to increase the mechanical strength compressive strength and flexural strength of mortar after 28 days of curing. Otherwise, there was a reduction in the drying shrinkage of mortar samples with a high recycled glass content of 80 and 100 %.