Circular Economy strategies for concrete: implementation and integration

Abstract

Concrete is the world's most widely-used anthropogenic material, and Circular Economy strategies will be key to addressing the myriad challenges that face its use today and into the future. Despite a rapid growth of research interest in developing Circular Economy strategies for concrete, this has mostly focussed on technical and environmental issues at the material and product scale. Holistic approaches considering wider social and political aspects as well as system-scale perspectives have been relatively neglected. This article uses a narrative review to investigate three outstanding questions to help address this gap: how concrete's material, product and system-scale attributes influence the interpretation of Circular Economy principles; how the full range of Circular Economy strategies can be implemented for concrete; and what the likely implementation issues will be when integrating different Circular Economy strategies (such as design for durability, component reuse and material recycling). From a product-scale perspective, it is argued that greater specificity is needed around the growing diversity of concrete materials and products in Circular Economy discourse - their properties are often distinct and hence specific strategies are not necessarily universally applicable. At the same time, a solely product-centric Circular Economy perspective is insufficient for concrete, and only joint consideration of structural and systemic perspectives will yield satisfactory solutions. ‘Soft’ perspectives of social, political and legal aspects cannot be viewed simply as an added bonus, but are essential to reconciling the ‘hard’ issues of technical, environmental and economic aspects that dominate discussions. Whilst concrete can and should have a key role in a Circular Economy, its success will require more than just extensions of linear economy thinking. • Circular Economy (CE) offers opportunities as well as challenges for concrete. • CE strategies must be applied at material, product and infrastructure levels. • Concrete circularity requires a system-level perspective. • Socio-economic and political environments are overlooked circularity drivers.