基于“表-深”联合监测方法的露天煤矿边坡破坏模式研究

Slope failure mode and slip evolution mechanism of open-pit coal mine based on surface-deep joint monitoring

为了确定魏家峁露天矿西南帮边坡滑移的破坏模式及滑移演化机理,提出滑坡治理和灾害防治方案,通过现场查勘、滑移体地质勘察、边坡深部位移与边坡表面位移联合监测以及数值模拟等措施,确定了边坡的滑移面位置、揭示了边坡岩体破坏演化机理和边坡破坏模式,查明了此次滑坡的主要原因。结果表明:边坡潜在滑移面在孔口下27~32m处;边坡位移呈现出"急剧增长-缓慢平衡-再次调整"的"L"型变化过程,现阶段边坡处于平衡调整的临滑状态;边坡滑移呈现出"开挖卸荷—剪切破坏"力学机理,边坡的宏观破坏模式为剪切型破坏;软弱夹层受到水润侵蚀,剥离推进后,岩体应力释放,成为此次边坡滑移的主要原因。

In order to determine the failure mode and evolution mechanism of slope sliding in the southwest side of Weijiamao Open-pit Mine,the position of slope sliding surface was determined,the failure evolution mechanism and failure mode of slope rock mass were revealed,the failure mode of the slope was found out and the control plan of the landslide was put forward,through field and geological survey of sliding mass,deep and surface displacement of slope joint monitoring.The results show that the potential slip surface of the slope was 27 ~ 32 m below the orifice;the displacement of the slope present a "L"type change process of"rapid growth-slow balance-readjustment",and the slope was in limit slip state at present;the slope slip presents a mechanical mechanism of "excavation unloading and shear failure",and the macro failure mode of the slope was shear failure;the weak interlayer was eroded by water and the stress of rock mass was released after striping advance which is the main reason of the slope sliding.