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This study explores the application of calcium carbide residue, desulfurization gypsum, and ground granulated blast slag as curing agents to solidify sludge. Through indoor experiments simulating dry-wet cycles and sulfate erosion, using unconfined compressive strength (UCS), X-ray diffraction, and scanning electron microscope as testing methods, the durability of solidified sludge against dry-wet cycles and sulfate erosion was studied. The objective is to provide technical support for the application of solidified sludge in engineering projects and promote the resource utilization of industrial solid waste. The results indicate that solidified sludge exhibits excellent durability against dry-wet cycles and sulfate erosion, with improved durability as the dosage of curing agent increases. In terms of dry-wet cycles, UCS initially increases but experiences a certain degree of decline as the number of dry-wet cycles increases, with the strength change rate exceeding - 35%, and failure strain gradually increases. As for sulfate erosion, UCS initially decreases following 1 day of erosion and subsequently shows a gradual improvement as the erosion time progresses. Higher sulfate concentrations lead to higher UCS, with strengths reaching up to 2.102 MPa, and failure strain gradually decreases. Microscopic tests revealed that, although dry-wet cycles initially weaken the structure and network of solidified sludge, increasing dry-wet cycles numbers leads to enhanced hydration reactions, resulting in higher content of hydration products and a denser microstructure. Experimental results indicate that using calcium carbide residue, desulfurization gypsum, and ground granulated blast slag as curing agents for sludge results in excellent resistance against dry-wet cycles and sulfate erosion.

来源平台：ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING