Utilization of municipal solid waste incinerator bottom ash (MSWIBA) in concrete as partial replacement of fine aggregate

Abstract

Enhancing sustainable economic development while maintaining environmental integrity is of paramount importance. In this context, the effective utilization of municipal solid waste incinerator bottom ash (MSWIBA) presents a significant opportunity. This study investigated an approach for harnessing the potential of MSWIBA by incorporating it as a partial replacement for fine aggregate in concrete mixtures. Twelve concrete samples were prepared with varying proportions of MSWIBA. The mechanical and microstructural properties of the samples were comprehensively investigated. Moreover, the environmental and economic advantages of these concrete formulations were assessed. The results revealed that the water absorption of the concrete samples without MSWIBA was higher than that of the concrete samples with MSWIBA, suggesting that the added MSWIBA could fill the internal pores of concretes. The water absorption rate curve could be divided into three stages, i.e., rapid decline, slow decline, and stable. The optimal replacement ratio of fine aggregate with MSWIBA was between 24.8% and 57.8%. Notably, when the replacement ratio surpassed 24.8%, MSWIBA positively influenced the development of compressive strength, but it still lower than that of composite Portland cement-based concrete (OPC). Furthermore, pore structure analysis indicated that the efficacy of pore refinement was achieved within a certain replacement threshold. However, the efficacy of pore structure refinement diminished beyond that threshold. The substitution of fine aggregate with MSWIBA aligns with the technical specifications and building material standards, thereby complying with the principles of effective utilization, sustainability, and environmental consideration pertinent to MSWIBA management.