An investigation on the fresh properties of self-compacted lightweight concrete containing expanded polystyrene

This paper presents the fresh properties of structural self-compacted lightweight concrete (SCLC) containing expanded polystyrene (EPS) assessed by means of slump flow, T50, V-funnel and L-box tests. Fifteen mixes including different water/binder (W/B) ratios, nano-SiO2 contents and EPS percentages (10%, 15%, 22.5% and 30% by volume) were designed. The change in slump flow by hauling time was also evaluated and was predicted with multiple regression equations.The results indicate that mixtures with density higher than 1900 kg/m3 (up to 22.5% EPS) generally satisfy the self-compactibility criteria of SCLC containing EPS. The nano-SiO2 addition has some negative effects on the fresh self-compacted concrete (SCC), but this is to be less for EPS mixtures. While, the slump flow of SCLC containing EPS decreased up to 6% by reducing the given W/B ratio, T50 and V-funnel times increased in the ranges of 23–29% and 18–48%, respectively. EPS inclusion in SCC shows an increase in the slump flow retention up to 17%. Additionally, by using nonlinear multiple regression, the slump flow with hauling time can be accurately predicted.

► EPS in SCC with density higher than 1900 kg/m3 (⩽22.5% EPS) is generally satisfactory.
► Using EPS aggregates increased both V-funnel and T50 times and improved flowability.
► Nano-SiO2 addition in SCLC has less negative effect on workability than W/B reduction.
► EPS inclusion in SCC shows an increase in the slump flow retention up to 17%.
► Multiple regression model can accurately predicate the slump flow change with hauling time.