INFLUENCE OF SILICA FUME INCORPORATION ON THE FRESH AND MECHANICAL PROPERTIES OF EXPANDED POLYSTYRENE (EPS) FOAMED CONCRETE

This paper aims to study both fresh and mechanical properties of lightweight concrete (LWC) incorporating expanded polystyrene foam (EPS) beads as a lightweight aggregates (LWA). Various mixtures of EPS foamed concrete are produced by partial replacing normal aggregates by 0%, 15%, 25% and 50% of EPS foam beads by volume. In EPS foamed concrete the ordinary Portland cement (OPC) was replaced by silica fume (SF) with different ratios 0%, 5%, 10 and 15% by weight. Sixteen mixtures are prepared to investigate the properties of EPS foamed concrete. The tests program includes determination of fresh density, slump, compacting factor, compressive strength, splitting tensile strength, flexural strength and modulus of elasticity. Generally, using of EPS beads in concrete decreases its mechanical properties, although the workability improvement. On the other hand, replacing the OPC with SF improves mechanical properties of EPS foamed concrete. This improvement continues to the percentage of 10% and ultimate improvement at the ratio of 5%. Modulus of elasticity improves in EPS foamed concrete with SF content till 25% EPS foam. The workability of EPS foamed concrete decreases with the increasing of SF ratios.