Impact of Recycled Aggregate on the Mechanical and Environmental Properties of Concrete: A Review

This review aims to present and discuss the mechanical and environmental properties of two different types of recycled aggregates obtained from construction and demolition waste (CDW): (۱) Recycled Concrete Aggregates (RCA) and (۲) Mixed Recycled Aggregates (MRA). In addition, the properties of the concrete in the fresh (workability, water/cement ratio) and hardened state (mechanical and durability properties), as well as the environmental impact of the concrete produced with the two types of recycled aggregates, are presented and discussed. Due to the heterogeneous composition of recycled aggregates, the concrete properties can be significantly variable. The systematic review concerns scientific papers published from ۲۰۱۰ to ۲۰۲۰ and it shows the importance of the selection process in order to obtain high-quality CDW as well as of the type of recycled aggregates on concrete properties. In particular, recycled concrete aggregates show a better quality and homogeneity than mixed recycled aggregates that make them more suitable for concrete. This work presents an overview on the influence of recycled aggregate quality on the physical, mechanical, and environmental properties of concrete. This updated review expands the original analysis by incorporating recent studies from ۲۰۲۲ to ۲۰۲۵, reflecting advancements in recycling technologies, processing methods, and environmental assessments. The integration of novel treatment techniques, such as carbonation and microbial enhancement, has shown promise in improving the quality of recycled aggregates, reducing water absorption, and enhancing mechanical properties. Furthermore, life cycle assessment (LCA) studies have provided deeper insights into the sustainability of recycled aggregate concrete, highlighting the importance of localized sourcing and optimized mix designs. The review also addresses emerging regulatory frameworks and economic incentives promoting the adoption of recycled aggregates in structural applications, offering actionable recommendations for practitioners and policymakers [۸۶, ۸۷].

کلیدواژه ها:

construction and demolition waste ، recycled aggregates ، compressive strength ، durability ، w/c ratio ، workability