Optimization of plastic waste integration in cement bricks

Abstract

AbstractImplementing plastic waste in construction materials is a sustainable disposal method to overcome plastic pollution. The current study aims to optimize the integration of plastic waste in cement bricks regarding their thermomechanical properties in order to develop an eco-friendly building material. Polyethylene terephthalate (PET) and high-density polyethylene (HDPE) partially substituted cement with different ratios (0, 2.5, 5, 7.5, 10, 20%). The type that achieved better thermomechanical performance further replaced the other brick components; sand and coarse aggregates to determine the optimum replacement scenario and best design mix. Laboratory experiments have been carried out to measure the compressive strength, indirect tensile strength, bulk density, and thermal conductivity of the new composites. The measured results revealed better performance for the samples with HDPE than PET. A boost in the compressive strength and indirect tensile strength was noticed for the samples obtaining a limited amount (up to 7.5%) of HDPE. However, a reduction in the tested mechanical properties occurs with higher substitution levels. With respect to thermal conductivity and bulk density, they decreased with the increase of plastic waste. The best mechanical behavior and the highest thermal resistance were obtained by partial replacement of coarse aggregates with 7.5% and 20% HDPE respectively. The results represent a good contribution to energy conservation, waste management and sustainability.