Effect of Polystyrene as a Partial Replacement of Normal Coarse Aggregate on Fresh and Hardened Properties of Self-Compacting Concrete

This experimental research covers studying fresh and some mechanical properties of self-compacting concrete (SSC) incorporating Polystyrene beads (PS) as a partial substitution with crushed coarse aggregate. Waste materials such as Polystyrene is difficult and not cost effective to recycle or to store. By recycling this material in concrete in order to produce a lighter weight concrete, will reduce the pollution burden that harms the environment and the landfill cost. This experimental study evaluates the effect of five different percentages of PS as a replacement by volume of normal coarse aggregate namely 0, 20, 40, 60 % with 1.75 % Gelnium (G), 60 % with 1.5 % G) with 0.45 water-binder ratio (w/b) on the mechanical and physical properties of concrete. For all SCC concrete mixtures, 10 % micro-silica was added, by weight of the cement, as an addition. Two different amounts of superplasticizer (G) have been added to achieve the SSC fluidity, at 1.5% and 1.75% of the cement weight. For example, both 1.5% and 1.75% of the superplasticizer were used in the 60% aggregate replaced sample. For this aim, workability (assisted by L-Box test, V-funnel test, Slump Flow test), compressive strength, splitting tensile strength, degradation test (assisted by UPV, mass loss, compressive strength and splitting tensile strength), flexural strength and toughness. In general, the test results illustrate that when the percentages of Polystyrene increases, all values in the tests reduces compared with the control specimens.