Compressive strength of laterite soil stabilized with rice straw ash and fly ash based geopolymer

Abstract

This study discusses the use of rice straw ash, fly ash and alkali activators (NaOH) to bind laterite soils, where the hardening process is carried out at room temperature to form geopolymers. Comparison of the binder composition used consisted of straw ash: fly ash: laterite soil that is 0.417: 0.167: 0.417 based on weight ratio, using a base activator (NaOH). Flow testing on new geopolymers shows that all materials are well bound and there is no segregation. The specimens are curing until 3, 7 and 28 days old. There are two curing methods used, which are keep in the room temperature and immersed in fresh water, to observe the resistance of the specimens to environmental. Experimental results show that laterite soil with straw ash-fly ash based geopolymer can provide sufficient compressive strength.