Flexural Behavior of One-Way Slabs Using Recycled Coarse Aggregate

This study investigates the flexural behavior of one-way reinforced concrete slabs incorporating recycled coarse aggregate (RCA) as a sustainable alternative to natural aggregate. A total of six simply supported slab specimens with dimensions of 600 mm × 1600 mm × 120 mm were casted and tested under four-point bending as distributed load. The experimental program examined the effects of two main parameters: RCA replacement ratio (0%, 50%, and 75%) and main reinforcement ratio with target concrete compressive strength of 25 MPa. The main parameters studied were ultimate load, mid-span deflection and tensile strain in main reinforcement. The results demonstrated that increasing the reinforcement ratio led to significantly enhanced the load-carrying capacity and stiffness of the slabs. In contrast to the increase in RCA replacement ratios. The results were compared with both the American and Egyptian codes, showing a good agreement between experimental findings and analytical results based on ACI and Egyptian codes. However, these improvements were associated with a reduction in ductility and energy absorption in some cases, indicating a transition toward less ductile behavior. The findings confirm the structural feasibility of using RCA in flexural members, provided that reinforcement and concrete design parameters are carefully optimized to balance strength and deformation capacity.