红沙泉露天煤矿西端帮边坡角度优化方案研究

Slopeangle optimization scheme for west end-wall of Hongshaquan open-pit mine

露天煤矿端帮边坡下压覆煤炭资源无法采出,提高端帮边坡角度对提高资料回采率具有重要意义。为了在保证边坡稳定性的前提下提高红沙泉露天煤矿西端帮边坡角度,在综合分析端帮边坡地质条件的基础上,分析了影响西端帮边坡稳定性的因素,包括岩体开挖及堆载、岩体物理力学性质及构造、边坡的整体坡形与台阶坡面角等。结合了岩土体物理力学参数,采用刚体极限平衡法和强度折减法对选取的典型坡面进行稳定性分析,并探索了端帮边坡角度对边坡稳定性的影响规律。结果表明,在当前端帮边坡角度为21°条件下,边坡的潜在滑动模式为贯穿坡面内部的整体圆弧式滑动,稳定系数为1.728且高于储备系数,稳定系数随边坡角度增加呈先显著下降后缓慢下降趋势,在满足储备系数1.2要求下,优化确定西端帮边坡角度可提升至36°。

The coal resources under the side slope of open-pit coal mine cannot be recovered,so it is important to improve the angle of the side slope to improve the mining rate.In order to improve the slope angle of the west end of Hongshaquan open-pit coal mine on the premise of ensuring slope stability,on the basis of comprehensive analysis of the geological conditions of the end slope,the factors affecting the stability of the west end slope are analyzed,including rock mass excavation and overloading,rock mass physical and mechanical properties and structure,slope shape and step slope angle,etc.Combined with the physical and mechanical parameters of rock and soil mass,the rigid body limit balance method and strength reduction method are used to analyze the stability of the typical slope.The influential law of slope angle on slope stability is also explored.The results show when the current slope angle is 21°,the potential sliding mode of the slope is the integral circular sliding through the inner slope,the stability coefficient is 1.728 and higher than the reserve coefficient,and the stability coefficient decreases significantly at first and then slowly with the increase of slope angle.Under the requirement of the reserve coefficient of 1.2,the west slope angle can be optimized and increased to 36°.