The effect of fly ash as coating powder on compressive strength of lightweight concrete

Abstract

Expanded polystyrene (EPS) has been used and studied for decades in lightweight concrete. Because EPS beads are incredibly light, using these beads in concrete will cause the particles to segregate. Furthermore, the hydrophobic nature of EPS materials weakens the bond between them and cement paste. This research will investigate the compressive strength of lightweight concrete using EPS beads as a coarse aggregate replacement, focusing on the effect of fly ash coating with a binder made from a mixture of Polyvinyl Acetate (PVA) and water. A comparison of density and compressive strength between normal concrete and concrete made from EPS beads was conducted in this study. EPS beads will replace 100% of coarse aggregate. Coated EPS beads that were being produced in this research have an average weight per volume of 246–251 kg/m3. The concrete that uses EPS beads coated with fly ash showed positive results for an increase in compressive strength of 8%, 20%, 38%, and 27% at the age of 7, 14, 28 and 56 days of concrete with EPS beads without modification.