Investigating the Viability of Using Recycled Coarse Aggregates from Construction & Demolition Waste

This paper takes a closer look at the potential of using recycled coarse aggregates (RCA) sourced from construction and demolition (C&D) waste as either partial or complete substitutes for natural coarse aggregates (NA) in both structural and non-structural concrete. It brings together insights from recent reviews and experimental studies, highlighting how RCA performs in three important mechanical tests: Aggregate Crushing Value (ACV), Aggregate Impact Value (AIV), and Los Angeles (LA) abrasion. The findings in the literature indicate that RCA typically shows higher ACV, higher AIV, and greater mass losses in LA abrasion (meaning it has poorer resistance to fragmentation and abrasion) compared to similar natural aggregates. This is largely due to the presence of adhered mortar, increased porosity, and angular shapes. However, when RCA is treated or processed—through improved crushing, removal or strengthening of the attached mortar, and proper grading—it can achieve properties that are suitable for a variety of concrete applications, often with suggested partial replacement rates and necessary pre-treatment.