Comparative analyses of circularity practices in civil and construction engineering between UK and Nigeria

The circular economy in the civil and construction engineering sectors is gaining momentum globally. The inadequate waste management system, especially in emerging nations, is quite concerning. Various waste sources such as construction and demolition (C&D), industrial wastes as well as agricultural wastes such as cassava peel, rice husk, and coconut fibre have been utilized in developing construction products. This study adopts the UK (United Kingdom) and Nigeria as two cases with critical analyses of the status quo and recommendations for promoting circularity. The existing studies on the circular use of waste construction products were comprehensively reviewed by mapping them against the Technology Readiness Level (TRL). The study addressed three research questions: (1) the existing locally available wastes used in civil and construction industries in the two studied countries, (2) the effects of these wastes on the properties of new construction products, and (3) visions to enhance circular use of wastes on civil and construction engineering practices. It is found that both countries have abundant industrial, agricultural, and demolition wastes that are potential materials for circularity in construction. While the TRL of utilizing these wastes is at an advanced stage in the UK, there is still a need for more concerted efforts to bring those wastes in Nigeria to a higher TRL. This study contributes to the existing body of knowledge by mapping the three aforementioned questions between the two studied countries, shedding light on continuous work in enhancing circular practices across the global civil and construction sectors.