露天煤矿工作帮边坡破坏模式及稳定性控制研究

露天边坡的稳定性是影响煤矿安全生产的重要因素,对其工作帮边坡破坏模式进行分析是有效地控制边坡稳定的前提。综合分析魏家峁露天煤矿工作帮边坡地质条件、边坡现状,并结合数值模拟计算,重点揭示边坡的位移特征、剪应变及塑性区扩展情况,对边坡失稳机理及破坏模式进行了分析,结果表明：力学机理上边坡岩体主要受开挖卸荷—剪切破坏影响,宏观表现上工作帮边坡主要发生蠕滑—拉裂型滑移破坏,边坡呈现出沿软弱层发生底部顺层后缘圆弧状的滑动,上覆粉土、粉砂层为坐落—平推型滑移。基于此,提出了“实时监测+疏干排水+清方剥离”的综合滑坡治理方案,提高了边坡稳定性,保障了矿山安全稳定生产。

Stability Analysis and Control of working Slope in Open-pit Coal Mine

Ensuring the stability of open pit slope is the front topic of its safety in production, and the stability analysis of working slope is the basis of effective control of slope stability. Combined with the geological conditions and present situation of the slope in Weijiamao opencast coal mine, through numerical simulation calculation and analysis, the failure mechanism and failure mode of the slope are analyzed from the most intuitive displacement characteristics of slope deformation, shear strain and plastic zone expansion. The conclusion shows that the slope slips along the bottom of the weak layer with circular arc along the bottom, and causes the failure of overlying silt and silt layer. The slope body is mainly excavated and unloaded and shear failure mechanism, macroscopical. The mode is shown as the creep and crack type traction landslide, which is the failure mode of the flat push which is cut by the arc of the rear edge of the bottom plate and the trailing edge of the bottom plate. According to this conclusion and in combination with the on-site fact, the comprehensive landslide control scheme of the "Real-time monitoring + dredging and drainage + stripping" is put forward to the slope stability control, the stability of the slope is improved, and the safe and stable production of the mine is guaranteed.