A novel lightweight concrete-fabrication and its thermal and mechanical properties

• Lightweight EPS concrete was produced by partially replacing EPS beads with foams.
• A noval method to evaluate homogeneity of concrete during setting was developed.
• Segregation of EPS concrete was significantly reduced at an optimum foam content.
• Strength of EPS concrete was enhanced by introduction of a proper amount of foam.
• EPS foamed concrete is ductile and exhibits a high energy absorption capacity.

The main objective of this study is to provide additional data on the effects of foam content on the workability, mechanical properties and thermal conductivity of EPS (expanded polystyrene) foamed concrete. In the experimental studies, mixtures were prepared by partially replacing EPS beads with foam with a bubble diameter of 25–100 μm; the resulting densities of the EPS foamed concretes in a fresh state were 400 kg/m3 and 800 kg/m3. The test results show that proper foam content introduced into the EPS mixture can greatly improve the workability, strength and thermal conductivity of EPS foamed concrete. Novel lightweight EPS concretes with densities 400 kg/m3 and 800 kg/m3 were produced, with strengths of 3.0 MPa and 0.009 W/mk, respectively, and thermal conductivities of 13.0 MPa and 0.25 W/mk, respectively. The recorded stress–strain curves of the material indicated that EPS foamed concrete is ductile. Moreover, EPS foamed concrete is capable of retaining the load after ultimate stress and has a high energy absorption capacity under compressive load.