Compressive strength and sustainability indicators of concrete manufactured with recycled refractory brick furnace waste

The use of recycled aggregates from demolished structures offers a promising and sustainable alternative to natural aggregates in concrete production, aligning with global efforts to conserve resources and protect the environment. This study investigates the environmental and structural advantages of incorporating recycled refractory brick furnace (RBF) waste, sourced from dismantled furnace wall structures, as a partial replacement for coarse aggregate (CA) in concrete. By substituting 15%, 30%, and 50% of CA by weight with RBF, the research evaluates the performance and sustainability of the resulting concrete mixtures. The findings reveal that replacing up to 30% of CA with RBF enhances the environmental sustainability and feasibility of concrete construction. At this replacement level, the concrete demonstrated a marginal decline in certain properties compared to normal weight concrete (NWC). Specifically, the density decreased by 2%, compressive strength by 13%, and structural efficiency by 7%. Despite these reductions, the 30% RBF concrete maintained sufficient performance to meet essential construction requirements. Notably, the global warming potential (GWP) of the 30% RBF concrete was only 1% lower than that of NWC, indicating minimal impact on carbon emissions. Furthermore, the sustainability index (SI) of the 30% RBF concrete was 10% lower than that of NWC, reflecting its improved environmental profile while still fulfilling structural demands. These results underscore the potential of RBF waste as a viable substitute for natural aggregates, offering a dual benefit of reducing the depletion of finite natural resources and minimizing waste disposal in landfills.