Optimizing the Tensile Strength of Polystyrene Lightweight Concrete: A Panacea for Sustainable Housing Development in Developing Countries

The use of polystyrene beads in concrete applications has been limited due to its perceived low strength properties. Tensile strength test is an important test that determines the vulnerability of concrete to tensile cracking due to the weight of the structural load. Water, sand, coarse aggregates, expanded polystyrene beads, and ordinary Portland cement are the materials used for this study. All the materials were batched according to their weight, except for polystyrene and coarse aggregates which were batched in volume after mixing them together. The polystyrene partial replacement level was considered at 12% of the coarse aggregate volume. The model equation adopted for this study was based on Scheffe’s {4, 2} simplex lattice design for both Pseudo component and component proportional models. The actual model was developed from the 28th day test result. The Mathlab and Minitab 16 software were used in this study to generate the actual mix ratios. The results obtained showed that both Pseudo component and component proportional models both produced an average split tensile strength of about 5.10N/mm2. This implied that the results of this study produced a split tensile strength result that varied between 18% - 19% of its compressive strength result. This showed that the materials and the mix ratios optimized in this study are suitable as building blocks for residential low rising buildings and as partition slaps for high rising buildings. The lightweight property makes it highly suitable for large scale application in high rising structures as internal partition slaps only.