ANSYS在煤矿开采数值模拟中应用研究

Application of ANSYS software to numerical simulation of coal mining

以典型矿井山东华丰矿、阜新五龙矿和北京大台井为例,利用 ANSYS 有限元软件,对煤矿开采引起的地表沉陷、冲击地压危险区域确定和俯伪斜采煤法参数优化进行了数值模拟分析。分别针对所处的地质条件和赋煤状况,建立了二维或三维有限元模型,模拟计算了地表沉陷曲线和最大沉陷位置,指出山东华丰矿随开采推进沉陷位移和影响范围将逐渐扩大,最大沉陷位移逐步向开采方向前移的规律,当开采 800 m 时出现最大下沉速度 3.5 mm/d,最大沉陷位移为 3.7 m。五龙矿 311面当开采 100m 和 400 m 时分别由于火成岩墙和应力集中区贯通导致顶板易断裂而极易发生冲击地压事故;大台井俯伪斜采煤法煤层倾角只有在 60o～67o 时,推采距离才对煤层顶板法向最大压应力具有明显影响,且顶底板法向最大位移规律为上部位移大于中部位移,西中部位移又大于下部位移,在煤层倾角 70°时,工作面超前支撑压力作用范围最小为 30 m,而下巷道支撑压力作用范围最大为 25 m,巷道数为 3 时,顶板下巷道超前支撑压力峰值位置为 5.3 m。ANSYS 计算结果表明,该数值模拟是合理的,与实际情况基本吻合,说明 ANSYS 在煤矿开采领域是一种有效的数值模拟工具。

Taking the typical coal mines such as Huafeng of Shandong, Wulong of Fuxin and Datai of Beijing of examples, the surface subsidence induced by coal mining, the dangerous regions determination of rockburst and the parameters optimization of oblique sublevel concentration mining were numerically simulated by using ANSYS software. According to the geology and coal reserves, the two-dimensional and three-dimensional models were established. The surface subsidence curves and the max subsidence values position were calculated for Huafeng mine. The results show that the subsidence displacements and influenced scopes increase with coal mining. The position of the max subsidence displacements gradually moves toward the mining direction. When 800m were mined, the max subsidence velocity 3.5mm/d appeared. The max subsidence displacements are 3.7m. In the 311 working face of Wulong mine, when 100m were mined the rockburst was easy to happen as the igneous rock wall effect. When 400m were mined the rockburst was also easy to happen as the roof failure induced by the stress concentration regions breakthrough. In the oblique sublevel concentration mining, only coal seam obliquities are 60o-67o, the mining distances have obvious effect on the max normal pressure stress of roof. The rules of normal displacements of roof and floor are that top displacements are greater than middle displacements, and middle displacements are greater than lower displacements. When the coal seam obliquity was 70o, the influenced scope of the advanced support pressure in the working face was 30m, and the scope of lower laneway was 25m. When three laneways are mined the peak position of advanced support pressure is 5.3m. The simulation results show the numerical analysis is reasonable with the practice. The ANSYS software is an effective way to coal mining.