The future of concrete recycling

Abstract

Building construction is a material-intensive process known for depleting natural resources, mainly gravel and sand, used in concrete production. At the same time, building demolition generates large amounts of construction and demolition waste (CDW), primarily consisting of end-of-life (EOL) concrete, a significant waste flow occurring in Europe's construction sector. The potential to deal with waste management and the uprising demand for new concrete in construction lies within circular economy-based solutions applied throughout the building's lifecycle. Steering in this direction, the European Union is endorsing a circular economy strategy that aims to utilize EOL concrete derived from CDW to produce new concrete and thus minimize virgin material inputs. These efforts have not been translated to a uniform framework for Europe, where practices, regulations for waste management, and market acceptance for secondary raw materials differ among member countries. In this project, different types of pre-demolition audits, demolition, and waste processing methods for EOL concrete are compared, showcasing the status quo across the EU and the Dutch case study, which portrays innovations that can shape the future of concrete recycling. An integrated LCA and LCC framework is applied from the demolition stage to waste processing and the production of materials for new construction to capture potential environmental and economic benefits and drawbacks at the end-of-life stage (EOL) of the building. The results showcase the pivotal role of BIM-supported pre-demolition audits in combination with selective demolition with benefits that include lower quantity of generated waste allocated to treatment and more components available for reuse. Finally, LIBS, a quality assurance tool for recycled aggregates, shows great potential in supporting a market for secondary raw materials in Europe.