The strength and water absorption of heated expanded polystyrene beads lightweight-concrete

When an earthquake occurs, buildings experience a movement or mass transfer. Therefore, the use of lightweight building materials is expected to reduce the effects of the earthquake. Research on the use of expanded polystyrene (EPS) as a substitute for aggregate has been done, but the results obtained are far from the requirements of structural concrete. This research tried to improve the mechanical ability of EPS concrete with the innovation of giving heat treatment to the EPS (heated EPS) to make the bonding capacity between the concrete components better than EPS without heat treatment. This research was a low-risk laboratory-based experimental study, which involves the process of making lightweight concrete from EPS beads that replace part of the aggregate. The method examined the lightweight concrete with partial replacement of aggregate with EPS beads (with the ratio of EPS beads to fine aggregate=0%:100%; 20%:80%; 40%:60%; 60%:40%; 80%:20%). The results found that the heat treatment of EPS beads changes the internal structure of EPS which can make the pores smaller and the surface structure of EPS becomes rough so that it can provide better bonding and adhesion between concrete elements. The compressive strength of heated EPS concrete tends to be higher 2-10MPa compared to EPS concrete without prior heat treatment.