Cheng Qiangqiang, Wang Haodong, Guo Yaben, Du Bin, Yin Qixiang, Zhang Linglei, Yao Yue, Zhou Nan
School of Architecture and Construction, Jiangsu Vocational Institute of Architectural Technology, Xuzhou 221000, China.
School of Mining Engineering, China University of Mining and Technology, Xuzhou 221000, China.
Materials (Basel). 2023 Jul 28;16(15):5314. doi: 10.3390/ma16155314.
Previous studies have shown that coal-based solid waste can be utilized in combination with cement, silica fume, and other modified materials to create a cemented backfill material. However, traditional cemented backfill materials have poor mechanical properties, which may induce the emergence of mining pressure and trigger dynamic disaster under complex mining conditions. In this study, the nanocomposite fiber was used to modify the traditional cemented backfill materials and a new cemented backfill material was developed using coal-based solid waste, nanocomposite fiber and other materials. Specifically, coal gangue, fly ash, cement, and glass fibers were used as the basic materials, different mass fractions of nano-SiO were used to prepare cemented backfill materials, and the mechanical enhancement effect of the compressive strength, tensile strength, and shear strength of the modified materials was analyzed. The results show that when the nano-SiO dosage is 1%, the optimal compressive strength of the specimens at the curing age of 7 d can be obtained compared with cemented materials without nano-SiO, and the compressive strength of the modified specimens raises by 84%; when the nano-SiO dosage is 1%, the optimal tensile strength and shear strengths of the modified specimens can be obtained at the curing age of 28 d, increasing by 82% and 142%. The results reveal that nanocomposite fibers can be used as additives to change the mechanical properties of cemented backfill materials made using coal-based solid waste. This study provides a reference for the disposal of coal-based solid waste and the enhancement of the mechanical properties of cemented backfill materials.
以往研究表明，煤基固体废弃物可与水泥、硅灰等改性材料联合使用，制成胶结充填料。然而，传统胶结充填料力学性能较差，在复杂开采条件下可能诱发矿山压力显现并引发动力灾害。本研究采用纳米复合纤维对传统胶结充填料进行改性，利用煤基固体废弃物、纳米复合纤维等材料研制出一种新型胶结充填料。具体而言，以煤矸石、粉煤灰、水泥和玻璃纤维为基础材料，采用不同质量分数的纳米二氧化硅制备胶结充填料，并分析改性材料抗压强度、抗拉强度和抗剪强度的力学增强效果。结果表明，当纳米二氧化硅掺量为1%时，与未掺纳米二氧化硅的胶结材料相比，7 d养护龄期的试件可获得最佳抗压强度，改性试件的抗压强度提高了84%；当纳米二氧化硅掺量为1%时，改性试件在28 d养护龄期可获得最佳抗拉强度和抗剪强度，分别提高了82%和142%。结果表明，纳米复合纤维可作为添加剂改变煤基固体废弃物胶结充填料的力学性能。本研究为煤基固体废弃物的处置及胶结充填料力学性能的提高提供了参考。
