Effect of Waste Glass on the Properties of Concrete

Abstract

Crushed waste glass bottles accumulating in stockpiles around New Zealand are an environmental concern, but also provide an available resource for potential use in concrete by partially replacing coarse and fine natural aggregates. The objective of this study was to test the fundamental properties of concrete that utilized 20% waste glass as a partial replacement for coarse and fine natural aggregates. It is demonstrated that the waste glass has a negative effect on concrete properties, including air content, compressive strength, and flexural strength, while also contributing to the problematic alkali-silica reaction. The use of supplementary cementitious materials such as fly ash or microsilica was found to improve the properties of concrete that utilized waste glass, especially with regards to inhibiting the alkali-silica reaction, and hence it was established that waste glass should be used with either fly ash or microsilica mainly due to concerns regarding the development of the alkali-silica reaction caused by the waste glass trialed in this study.