采动影响下露天矿排土场边坡稳定性分析

Stability analysis of dump slope of open-pit mine under the influence of mining

露天矿排土场压占大量的煤炭资源,为提高煤炭资源的采出率,同时保证边坡的稳定,必须确定井工开采终采线位置。以哈尔乌素露天矿区排土场下的煤炭资源进行井工开采为例,采用PHASE2软件建立数值计算模型,分析4号和6号煤层开采对排土场边坡位移场、最大剪应变和安全系数的影响,确定了4号和6号煤层终采线位置。结果表明:随着4号和6号煤层的开采,边坡最大水平位移和最大垂直位移均呈非线性增大趋势;边坡安全系数均呈非线性减小的变化趋势;4号煤层终采线距离1260平盘坡顶线右侧的水平距离为98 m,6号煤层终采线距离1260平盘坡顶线右侧的水平距离为35 m。

The waste dump of open-pit mine occupies a large amount of coal resources.In order to improve the extraction rate of coal resources and ensure the stability of the slope,the location of the stopping line of underground mining must be determined.Taking the underground mining of coal resources under the waste dump of Haerwusu open-pit mining area as an example,a numerical calculation model is established by PHASE2 software to analyze the influence of the mining of No.4 and No.6 coal seams on the displacement field,maximum shear strain and safety factor of the waste dump slope,and determine the positions of the stopping lines of No.4 and No.6 coal seams.The results show that with the mining of No.4 and No.6 coal seams,the maximum horizontal displacement and maximum vertical displacement of the slope increase nonlinearly,the safety factors of slopes show a nonlinear decreasing trend;the horizontal distance from between the stopping line of No.4 coal seam and the right side of 1260 flat slope top line is 98 m,and the horizontal distance between the stopping line of No.6 coal seam and the right side of 1260 flat slope top line is 35 m.