نوع مقاله : مقاله پژوهشی
عنوان مقاله English
نویسندگان English
This study investigates the use of a specific type of treated municipal wastewater from one of the Iranian cities as a substitute for mixing water in concrete. In addition, metakaolin (12.5% by weight of cement) and fibers were incorporated into the concrete mixtures. The chemical characteristics of the wastewater were carefully analyzed, and after confirming the absence of significant harmful substances, concrete specimens were prepared with various wastewater replacement ratios (0%, 50%, 70%, and 100%) and tested for mechanical strength and durability. The results indicated that replacing up to 50% of the mixing water with the studied treated wastewater, in combination with additives, not only did not reduce the concrete’s properties but even improved some of its strength characteristics. In contrast, replacement levels above 70% without the use of additives led to a significant deterioration in the mechanical properties of the concrete. Metakaolin, through its pozzolanic reactions, and fibers, by controlling microcracks, played crucial roles in enhancing compressive strength, impact resistance, and durability under Freeze–Thaw Cycles, particularly in samples containing 100% wastewater. The combined use of treated wastewater, metakaolin, and fibers can result in the production of sustainable (“green”) concrete with desirable performance and durability, while effectively reducing freshwater consumption and environmental impacts. Since the characteristics and quality of municipal wastewater vary from city to city, the mix design proposed in this study cannot be universally applied, and separate experimental evaluations should be conducted based on the local wastewater quality and concrete properties.
کلیدواژهها English