Construction and demolition waste in geopolymer concrete technology: a review

Geopolymers are a relatively new generation of construction materials developed with industrial by-products and supplementary cementitious materials (SCMs) with high silica and alumina contents. In recent years, the demand for SCMs has increased significantly due to action plans on global climate change. In addition, construction and demolition wastes (CDWs) are a major concern in the construction sector and using them through the geopolymerisation process has therefore attracted the attention of researchers worldwide. This paper summarises the literature pertaining to the use of CDWs such as concrete, brick and ceramic as source materials in geopolymer technology, either alone or with SCMs. The literature indicates that CDW materials work well as the main source materials in geopolymer technology. However, due to the various parameters in geopolymerisation, research should move toward defining threshold levels and acceptable criteria rather than simply the best composition outcomes.