Development of recycled masonry concrete blocks using crushed brick masonry debris: physical, mechanical, and sustainability characteristics

The expansion of global infrastructure is contributing to the depletion of natural resources and other environmental concerns, primarily owing to the generation of construction and demolition waste. Recycling and reuse of this waste offers a feasible approach to resource conservation and enhancement of sustainability. In this study, an attempt was made to explore the feasibility of crushed brick masonry debris (CBM) for the development of recycled masonry concrete blocks (RCB). CBM as fine aggregate in varying substitution levels were incorporated to develop RCB, which were assessed for physical, mechanical, and durability properties. The results revealed that the utilization of CBM in concrete blocks exhibits satisfactory performance across all parameters, with the 50–75% CBM substitution showing optimal results. RCBs displayed dimensional stability, appropriate densities, and water absorption within acceptable limits. Compressive strength of the blocks ranged between 4.68 and 6.14 MPa for various substitution levels, better than commercial blocks. Microstructural analysis revealed beneficial crystal formations supporting mechanical performance. Notably, RCBs showed significant reductions in embodied energy (47.65–64.59%) and embodied carbon (5.67–31.56%) compared to conventional blocks. Thus, utilizing recycled materials in the manufacturing of concrete blocks not only showcases viability but also enhances the progression toward sustainability.