Physical and mechanical properties of lightweight concrete with the incorporation of waste disposal polyurethane foam as coarse aggregate

Industrial waste in engineered concrete mixes is an enormous step towards sustainable development. Polyurethane foam waste (PUFW) is mainly generated by the refrigeration, automobile, and construction industries. Day by day, large amounts of PUFW are incinerated and disposed of in landfills, which not only affects the environment but also leads to the loss of land usage. On the other hand, with the improvement of financial benefits, environmental benefits, and structural style, the demand for lightweight concrete (LWC) is also increasing. This study investigated the incorporation of rigid PUFW as coarse aggregate in LWC. Various proportions of PUFW replacement by volume (40%, 50%, 60%, 70%, and 80%) were examined to formulate the LWC mixtures. The physical and mechanical properties of the LWC were tested and compared with conventional concrete. The results showed that the compressive strength reached more than 17 MPa when LWC was made with 40%, 50%, and 60% PUFW content, satisfying the compressive strength of structural LWC. At 70% PUFW content, the compressive strength was satisfactory for semi-load bearing strength, and at 80% PUFW content, it was suitable for insulation concrete. In all mix proportions, the density value was less than 2000 kg/m3, which was satisfactory for LWC.