Mechanical Performance and Sustainability Assessment of Construction Waste–Incorporated Concrete for Socio-Economic and Environmental Benefits

The rapid growth of construction activities has led to a significant increase in construction and demolition waste, posing serious environmental and socio-economic challenges. This study investigates the feasibility of incorporating multiple construction waste streams—plaster waste, recycled concrete, mortar waste, broken tiles, steel slag, and crushed blocks—into concrete as partial replacements for natural fine and coarse aggregates. Laboratory experiments were conducted to compare the mechanical properties of conventional concrete (CC) and construction waste incorporated concrete (CWICM). Concrete cubes and beams were cast and tested for compressive and flexural strengths at 7, 14, and 28 days of curing. Results show that while CC consistently achieved higher strength values, CWICM demonstrated progressive strength gain with age, reaching 10.00 N/mm² compressive strength and 2.56 N/mm² flexural strength at 28 days. Statistical regression analysis indicated that curing age and maximum crushing load were the most significant predictors of compressive strength. Although strength reduction was observed in waste-based mixes, the performance remains suitable for low-load structural and non-structural applications such as lintels and partition walls. The findings confirm that recycling construction waste in concrete can reduce landfill burden, conserve natural aggregates, lower environmental pollution, and contribute to sustainable construction practices, especially in developing economies.