This experimental study evaluates the properties of concrete produced using natural coarse aggregate (NCA) and recycled coarse aggregate (RCA) obtained from demolished structures, with a particular focus on how RCA content influences compressive strength. The objective is to assess the feasibility of employing RCA as a sustainable alternative to natural aggregate in structural concrete. A series of mixes incorporating four RCA replacement ratios (0%, 50%, 75%, and 100%) was developed to produce an eco-friendly concrete that reduces construction related waste and environmental pollution. The results show that concrete compressive strength decreases as the RCA replacement ratio increases. At 28 days, the reductions in compressive strength were 7.80% for 50% RCA, 12.89% for 75% RCA, and 14.45% for 100% RCA compared with the natural aggregate control mix. However, the reduction up to 50% RCA was relatively small, indicating that partial replacement can meet structural performance requirements while supporting sustainability goals. The findings also confirm that compressive strength increases significantly with curing age, although higher RCA content leads to lower early age and long-term strength. Notably, the 0% and 50% RCA mixes retained more than 90% of their 28 days strength at 120 days. A parallel numerical analysis conducted using ABAQUS demonstrated a consistent increase in axial deformation with higher RCA replacement ratios, confirming the associated reduction in stiffness and aligning with the experimental mechanical trends. Overall, the results highlight the importance of considering both curing age and RCA content when evaluating the mechanical behavior of recycled aggregate concrete and demonstrate its potential for sustainable structural applications.