Investigating the potential of waste polyethylene in concrete

Abstract

It is significant to use recycled waste plastic bags in concrete to solve the issue of the disposal of leftover polyethylene in the environment. This research incorporated the plastic bags’ polyethylene into concrete and evaluated the mechanical properties of concrete, to reduce cracking to some extent and increase the tensile & flexural strengths and deformation capacity. Six mixtures were used with varying percentages of waste plastic bags (i.e., 0%, 0.3%, 0.6%, 0.9%, 1.2%, and 1.5%). The sorptivity test was conducted following ASTM C1585 and the volume of permeable voids test was according to the ASTM C642 requirements. The pullout strength of the steel rebar in a concrete cylinder was also determined. With waste polyethylene, it was noted that the flexural strength increased, pull-out bond strength declined and initial sorptivity increased. This decline in the volume of permeable voids was due to the heterogeneity of the mixture which leads to the low density of the mixture due to waste plastic bags. Experiments proved that substituting plastic bags for fine aggregates in concrete, increases flexural and split tensile strengths while decreasing compressive and pullout strength.