Eco-efficient high performance white concrete incorporating waste glass powder

Abstract

Portland cement and supplementary cementitious materials (SCM) are crucial components in the mixture design of High-Performance Concrete (HPC). In certain regions, the constrained ready market availability of SCM may limit the widespread adoption of HPC, namely when a long-term supply is envisaged. These circumstances demand research into sustainable and cost-effective HPC mix designs independent of expensive and imported SCM, such as silica fume. Using locally available SCM reduces costs and the carbon dioxide (CO2) emissions associated with HPC production, while also assigning value to abundant industrial waste or by-products, such as glass powder. This study presents a wide range of more environmentally friendly white HPC formulations suited for architectural applications. The proposed formulations incorporate significant proportions of limestone filler and waste glass powder with varying fineness, serving as substantial partial replacements for white cement. An integrated assessment of engineering properties was conducted, including flowability, electrical resistivity, mechanical strength, and ecological balance. Response surface models of the material behaviour reveal that the water-to-cement weight ratio (w/c) and the glass powder-to-cement weight ratio (GP/c) have a significant influence on both the engineering properties and the ecological footprint of HPC. Regression models were used to obtain the high-flowable HPC. Five optimal mixtures were selected featuring significant partial replacement of cement (c) by limestone filler (Lf) and glass power (GP), with Lf/c is an element of[0.38;0.78] and GP/c is an element of[0.269;0.394]. These mixtures reached cube compressive strengths ranging from 90 to 100 MPa, flexure strengths in the 13-15 MPa range, and resistivity levels between 90-180 ohm.m at 28 days.