Geopolymer Concrete with Recycled Concrete Aggregate

Abstract

Geopolymer concrete replaces cement based binder with a binder which contains no Portland cement. One type of geopolymer binder is that which contains fly-ash activated by an alkaline solution of sodium silicate and sodium hydroxide. Utilising recycled concrete waste from construction and demolition sites, that would otherwise be disposed of into landfill, as a source of aggregate offers a potential environmental and economic benefit. The term recycled concrete aggregate (RCA) is used to define aggregate produced from crushed demolition and construction waste. Research has been conducted into both recycled concrete aggregate (RCA) and geopolymer concrete; however there was limited published data on using RCA in geopolymer at the time of this research. This paper reports on the outcomes of the research into the mechanical properties of geopolymer concrete with recycled concrete aggregate as partial replacement of the natural coarse aggregate which indicate the potential of incorporating RCA in geopolymer concrete mixtures.