Influence of Recycled Waste High Density Polyethylene Plastic Aggregate on the PhysicoChemical and Mechanical Properties of Concrete

Utilisation of waste plastic materials as aggregates in concrete manufacturing could be a partial solution to the environmental and ecological challenges associated with the use and disposal of plastics. This study examines the possibility of using waste High Density Polyethylene (HDPE) as a partial replacement for coarse aggregate in concrete formulation at various plastic compositions (0%, 2%, 4%, 6% and 8% by weight of the coarse aggregate). Particle size distribution (PSD) and specific gravity tests were conducted for the plastic aggregates. The influence of the waste HDPE on the fresh and hardened state properties of the concrete, the workability, compressive and flexural strengths were investigated. The effect of water on the compressive strength of the composite was also determined for the various compositions. Results of various tests suggest that workability of the fresh concrete decreased with increasing plastic content, the compressive strength of the concrete decreased appreciably with increase in the plastic content and was found to be lower than normal concrete. The 28th day flexural strength decrease marginally with increase in plastic content in the concrete. Also the mass of water absorbed by the concrete samples increased with increasing plastic content. Despite the effects of waste HDPE on the various properties of the composite, results were all found to be within acceptable limits. Thus waste HDPE materials could be considered for use in formulation of concrete.