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In response to the dilemma of the scarcity of mineral additions and the high cost of long-distance transport in Hotan, Xinjiang, China, this paper presented an activation process study on the feasibility of volcanic rock powders unique to this region as mineral additions. This study explored the activity-enhancing effects of volcanic rock powder via three methods: physical activation process, chemical activation process, and thermal activation process. The results showed that physical grinding improved the particle size distribution and enhanced the ‘microaggregate’ effect. For every 80 m2/kg increase in specific surface area, the particle size decreased by approximately 0.7 μm, and the 28-day activity index increased by up to 4%. In the chemical activation process, the optimal combination scheme of 6% CaO, 2% CaCO3, and 2% CaSO4·2H2O increased the 28-day strength of volcanic rock powder mortar specimens by approximately 20%, achieving an activity index of 82%. Thermal activation studies showed that the low-temperature heat treatment interval of 300 °C to 700 °C increased the 28 d activity index of volcanic rock powders by 12 to 22 percent. However, when the temperature reached the high-temperature interval of 800 °C to 1400 °C, it, rather, inhibited the activity enhancement. A combination of the three activation methods (physical milling with a specific surface area of 560 m2/kg after heat treatment at 600 °C, chemical activation with 6% CaO, 2% CaCO3, and 2% CaSO4·2H2O) resulted in an activity of up to 86% for the volcanic rock powder. The activity enhancement by different activation methods provided a theoretical basis and practical reference for the application of volcanic rock powder as a mineral additions in Hotan, Xinjiang.

In addressing the dual challenges of sustainable waste management and environmental conservation in the construction industry, particularly the disposal of waste tire crumb rubber (CR) and the demand for eco-friendly building materials, this study explores a novel solution. It examines the sustainable incorporation of waste tire crumb rubber and mineral additions—namely silica fume (SF), marble slurry powder (MSP), and fly ash (FA)—as partial substitutes for natural fine aggregates and cement in concrete. Through comprehensive testing of seventeen concrete samples, the study reveals that the specific mix of R10S5M10F15 that contained 10% crumb rubber as replacement of fine aggregates, and 5% silica fume, 10% marble slurry powder and 15% fly ash as replacements of cement, not only achieves compressive and split tensile strength comparable to the control mix, while the 90 days flexural strength was improved by 4.48%; credited to SF’s pozzolanic action and the filler effects of MSP and FA, but also that the inclusion of CR, while reducing compressive strength due to material variations, enhances ductility and improves resistance to sulfate and acid attacks, despite increasing water absorption. The primary goal of this research is to investigate the feasibility and effectiveness of using waste materials in concrete to foster more sustainable construction practices. The objectives include a detailed assessment of the mechanical properties and durability of concrete incorporating these waste materials, aiming to determine the optimal mix proportions for their effective utilization. This study’s novelty lies in its detailed analysis of the synergistic effects of combining CR, SF, MSP, and FA in concrete, contributing to the field by offering a sustainable alternative approach to traditional concrete formulations and highlighting the delicate balance required for optimized concrete performance.