Innovative Ultra-High Performance Concrete (UHPC) Incorporating oil ash and electric arc furnace dust

Extensive modern industrialization produces massive amounts of hazardous waste, which becomes an enormous concern due to their harmful impacts on human health and the ecosystem. Tackling hazardous waste with a more secure approach is crucial. The use of hazardous wastes as building materials makes a significant contribution to environmental protection and supports sustainable growth in the construction industry. This study aims to develop eco-friendly innovative ultra-high-performance concrete (UHPC) comprising regionally accessible industrial waste materials such as oil ash (OA) and electric arc furnace dust (EAFD) as a partial replacement of micro silica (MS) and natural fine sand to minimize its environmental impact and reduce the amount of these wastes dumped in lakes and landfills, as well as diminishing the cost of UHPC. A total of 13 various UHPC mixes with varying replacements of MS and fine sand by OA and EAFD, e.g., 0 %, 5 %, 10 % and 20 % of the total mass of MS and fine sand, were made. The UHPC with 0 % replacement was maintained as a reference. The mechanical characteristics were investigated through compressive and flexural strength of the specimens. The ductile performance was examined through load-deflection, energy absorption capabilities, and fracture toughness. Lastly, the durability characteristics such as water absorption, water permeability, drying shrinkage, chloride penetrability, electrical resistivity and sulfate resistance was also examined. The outcomes demonstrated that 20 % OA and 5 % EAFD replacement of MS were the optimum levels of replacement that could produce sustainable UHPC with comparable mechanical and durability performance over the reference UHPC.