Concrete Limits: A sociometabolic analysis of the feasibility of the Circular Economy approach for the concrete sector

Abstract: The concrete sector is a major contributor to global greenhouse gas emissions; consumes substantial amounts of natural resources and serves as a significant source of global waste. The Circular Economy approach has been put forward as the solution to these environmental issues, but the overall effectiveness of the approach has been called into question by existing research. The aim of this thesis was to evaluate the potential effectiveness of the Circular Economy approach in the concrete sector, with a focus on the barriers for adoption of circular strategies, and how the approach can be adapted to increase its ability to reduce material and energy consumption. The sociometabolic regime framework was used to analyse the effectiveness of the concept. Literature on this framework guided an analysis of data on concrete production and in-use stocks as well as findings from interviews conducted with representatives from the concrete and building sectors and academic experts. The findings indicate that, from a sociometabolic perspective, the most significant barriers to undermine the effectiveness of the Circular Economy transition in the concrete sector are the continued expansion of concrete in-use stocks and the growth-oriented nature of the CE approach. Another finding was that part of what has made concrete a dominant building material is that it is easy to produce cheaply, and thus easy to profit from. This presents a clear barrier for implementing circularity, as this very attractive quality of concrete, its cheapness, would be eroded if the CE approach was implemented. Finally, the research concludes that the Circular Economy approach could be made more effective, in the case of concrete, by prioritising sufficiency and the contraction of in-use stocks. This would lead to greater effectiveness in bringing down levels of resource and energy use.