Maximizing the utilization of construction waste in cement-stabilized macadam based on mechanics and durability performance

The substantial accumulation of construction and demolition waste (CDW) adversely affects both the economy and the environment, making its recycling a crucial strategy to mitigate this issue. To elucidate the application effectiveness of CDW in cement-stabilized macadam (CSM), particularly concerning durability, this study analyzes the impact of recycled aggregate content on the physical and mechanical properties of cement-stabilized macadam. It proposes acceptable maximum recycled aggregate content and composition that do not result in a significant decline in mechanical properties. The mechanical, durability, and fatigue characteristics of cementstabilized macadam with recycled aggregates (CACSM) were evaluated. Utilizing a genetic algorithm combined with a backpropagation (BP) neural network (GA-BP), the durability performance of CACSM was predicted. The findings indicate that the recycled fine aggregate content can reach up to 58 %, while the recycled coarse aggregate content can reach up to 25 %, without compromising the mechanical strength of CACSM compared to traditional CSM. Furthermore, when the recycled fine aggregate content is less than 45 %, the durability and fatigue performance of CACSM surpass those of CSM. The GA-BP model demonstrated a strong fitting performance for predicting the durability of CACSM.