De-risking resource recovery value chains for a circular economy – Accounting for supply and demand variations in recycled aggregate concrete

The use of recycled material as an alternative constituent material in products replacing natural aggregate, if done at an industrial scale, exposes the supply chain to several risks. Raw material supply, which traditionally could be met on demand by extracting natural resources, could be replaced by providing recovered resources as a re-purposed raw material. This paper analyses the supply chain associated with the use of coarse recycled concrete aggregate, replacing natural coarse aggregate, to produce a new concrete product referred to as recycled aggregate concrete. If the recycled concrete aggregate is used in the production of concrete, the supply of coarse aggregate for ready-mix concrete production will depend on the supply of crushed recycled concrete aggregate, creating increased variability in supply, as this could not be produced on demand. Using dynamic model-based simulations, this paper analyses the behaviour of a supply chain using recycled concrete aggregate as a constituent material in concrete. Simulations of variability and differences in supply and demand, while meeting the market demand for the product, are developed.