A Comparative Study Investigating the Feasibility and Potential ofUtilising Polymer, Demolition & Glass Waste as a Partial Replacementfor Fine and Coarse Aggregate in Concrete

Abstract

The construction industry is a key CO2  contributor. Contemporary research focuses on formulating cement replacement composites; however, less attention is deliberated to formulating fine/coarse aggregate replacement composites. The waste from different fields contributes enormously to adverse environmental effects, thus necessitating reuse/recycling. The demolition/reconstruction of old buildings/infrastructure is adding further to the waste contribution by the construction industry. The total quantum of fine/coarse aggregate in the construction industry is estimated to be around 20 billion tons, contributing around a billion tons of CO2. Therefore, even partial replacement of virgin sand/coarse aggregates with various waste materials like glass, rubber, plastic,tyres, recycled concrete and others will economise the cost of manufacturing the concrete with reduced CO2  footprints as eco-friendly materials. This study conducted a comparative analysis for investigation of the characteristic compressive and split tensile strength of concrete composites with partial replacement of virgin sand/coarse aggregate by 10-30% of Crushed Glass (CG), Crumb Rubber (CR), Recycled PET Bottles (RPB), Recycled Concrete Aggregate (RCA) and 5-10% of Shredded Tyres (ST). Generally, all the composites demonstrated par/ better strength with the control mix, achieving the target strength of C55/67 concrete. The composites with CG, RPB and RCA exhibited an improvement in compressive strength, attaining more than 70 MPa (high-performance concrete strength) and up to 10% improvement in split tensile, attaining 4.3 MPa. CR and 5-10% ST exhibited a slight decrease in compressive strengths. All the composites formulated in this study explicate their diverse uses for multipurpose infrastructural applications in the construction industry as improved,economical, eco-friendly waste absorbent composites.