Effect of Elevated Temperature on Mechanical Properties of Waste Polymers Polyethylene Terephthalate and Low Density Polyethylene Filled Normal Concrete Blocks

Thermal properties of M30 normal concrete block (NC) were compared with concrete filled with waste poly ethylene terephthalate and waste low density polyethylene aggregates which were used as partial replacement of sand in the production of concrete blocks (plast-cretes). Tests were carried out using 100mm×100mm Cubes and 100mm×200mm Cylinder for Compressive and Split tensile Test respectively. The mechanical properties of normal concrete and plast-crete were studied and compared over two temperature regimes at 100°C-400°C and 400°C-800°C. The compressive and Split Tensile strength of normal concrete increased slightly from 100°C-400°C, and reduced from 400°C-800°C. However, the compressive and split tensile strength of the plast-crete showed a gradual reduction from 100°C-400°C and this continued from 400°C-800°C, and became more pronounced as the percentage of waste plastics in the plast-crete increased. The percentage of weight loss for the normal concrete increased from 100°C-400°C, this increase continued from 400°C-800°C. The plast-crete also showed an increase in the percentage weight loss for both temperature regimes and the percent weight loss became more pronounced as the percentage of waste plastics in the plast-crete increased. The normal concrete showed greater spalling than the plat-cretes. Even with the slight reduction in strength with increasing temperature, Plast-cretes can still be applied in areas where low temperature and minimal load bearing applications are needed such as fancy blocks, pedestrian walk ways, slabs, partition walls, fences, houses and light traffic structures