露天矿端帮煤柱回收井工开采工作面推进方向的优化

为科学优化井工开采工作面的推进方向，保证边坡稳定的同时进一步提高煤炭采出率，以平朔矿区平面露井协采工程实践为背景，采用相似材料模拟实验的方法，研究了露天矿端帮煤柱回收过程中顺坡开采和逆坡开采对边坡变形破坏影响的差异性，构建力学模型分析了引起工作面煤壁侧垮落角小于开切眼侧垮落角的根本原因。研究结果表明，平朔矿区类似地质与采矿条件下，上覆岩层破断机制的不同，导致开切眼侧垮落角与煤壁侧的垮落角相差约7°，且顺坡开采有利于边坡稳定。基于以上结论，若采用顺坡开采方式，不但可以减小井工开采对边坡稳定的影响，还可以进一步缩小露井协采边界参数，采出更多的端帮压煤。

Optimization of underground mining development direction about end slope coal pillar recovery of open-pit coal mine

In order to scientifically optimize well mining working face advancing direction，further improving the coal recovery rate at the same time to guarantee the stability of slope，under the background of open-underground mining engineering practice in Pingshuo mining area，through similarity simulation，the different influence about deformation and failure of along slope mining and inverse slope mining under end slope coal pillar recovery was studied.Then mechanics model was constructed to analyze why the working face wall side caving angle is less than open-off cut side caving angle.The result shows that in the geological and mining conditions of Pingshuo mining area，the working face wall side caving angle is 7°，less than open-off cut side caving angle because of different overburden fracture mechanism，and the along slope mining is conducive to the slope stability.Based on the above conclusions，if use the along slope mining way，not only can reduce the influence of deformation and failure to the slope，but also can further narrow the boundary parameters of open-underground mining，and produce more end slope coal.