Mechanical properties of lightweight expanded polystyrene concrete containing fly ash

Each year more than 90 million tonnes of fly ash is generated in India; however, the use of fly ash in cement and concrete production is less than 15 percent. With a view to increase its utilisation further in concrete industry, lightweight expanded polystyrene (EPS) concretes were developed using high volumes of fly ash (30 and 50 percent). The present study covers mechanical properties of these lightweight concretes designed for a wide range of concrete densities ranging from 550 to 2200 kg/m 3. The results indicate that the compressive strengths of lightweight EPS concretes containing fly ash show a better strength gain rate even after 28 days, unlike that reported for EPS containing ordinary Portland cement and silica fume in literature. It was also found that the failure of these concretes both in compression and splitting tensile strength tests and stress-strain tests was gradual as was observed earlier for the concretes containing plastic shredded aggregates. EPS concretes exhibited only local failure and the structural integrity of the concrete also was not affected much.