Recycled aggregate in concrete production : a new approach

Construction and demolition waste is attributed with a large portion of landfill space around the world (Pacheco-Torgal et al. 2013). Recycling construction and demolition waste has been heavily researched in order to discover solutions for reducing landfill space. The use of crushed concrete waste as recycled aggregate serves as a solution with outstanding potential for reducing landfill volume. Conversely, recycled concrete, as it is known, is characterised by a large physical and mechanical shortcomings (Li et al. 2008). The deficiency of strength exhibited by recycled concrete does not permit it to surpass natural concrete in terms of mainstream practical usage (Kou et al. 2012). To achieve recycled concrete which challenges natural concrete, it must undertake additional strengthening processes. However, supplementary procedures required for improving recycled concrete quality must closely equal practicality and monetary expenditure of natural concrete. Review on the effects of incorporating recycled aggregate, sourced from construction and demolition waste, on the carbonation behaviour of concrete was conducted (Silva et al. 2015). Various influencing aspects related to the use of recycled aggregate, such as replacement level, size and origin, as well as the influence of curing conditions, use of chemical admixtures and additions on carbonation over a long period of time were identified.