Engineering performance of lightweight geomaterial influenced by EPS density and mix ratio

This paper highlights the engineering behavior of an expanded-polystyrene (EPS)-bead-based fly ash geomaterial (FAGM). The proposed geomaterial was prepared by blending EPS beads of different densities and fly ash contents with cement as a binding agent. The effects of three different EPS bead densities (25, 30 and 35 kg/m³), four EPS mix ratios (0.5–2.0%) and two cement contents (15 and 20%) on density, compressive strength at three different curing periods, 7, 28 and 90 days; and elasticity modulus were studied. It was concluded that the behavior of FAGM prepared with low-density and low-content EPS is analogous to that of FAGM prepared with high-density and high-content EPS. To evaluate the performance of FAGM as a lightweight and strong material, an empirical ratio of strength to density is defined. FAGM with low-density and high-content EPS can be used as an efficient lightweight filling material, whereas FAGM with high-density and low-content EPS can be used as a strong filling material. Moreover, the geomaterial, which is mainly formed from a freely available industrial byproduct, can be strongly used as a replacement for EPS geofoam blocks.