Properties, durability and microstructure of concrete incorporating waste electrical and electronic plastics as partial replacement for aggregates in concrete

Abstract

This paper presents the results of an experimental study to assess the properties, durability and microstructure of concrete incorporating different types of Waste Electrical and Electronic Plastic (WEEP) as partial replacement of both fine and coarse natural aggregates. These include acrylonitrile-butadiene-styrene, polycarbonate acrylonitrile-butadiene-styrene and high impact polystyrene. Concrete mixtures studied contained 5%, 10%, 20% and 30% WEEP replacement for the natural aggregate. Metakaolin and condensed silica fume were incorporated to enhance the performance of hardened concrete. Results show that all mixes achieved a minimum structural strength of 25 MPa. It was observed that concrete made using WEEP had a lower mechanical strength and durability performance compared to the control mix. This was mainly attributed to the poor bonding between the natural aggregate and WEEP due to the smooth surface associated with WEEP. Microscopy analysis revealed that the pozzolans increased the density of the concrete matrix and reduced the interfacial transition zone which in turn increased the overall performance of mixes containing WEEP.