我国西部矿区大部分位于山区及丘岭地区,这种条件下开采往往会导致滑坡灾害的发生。利用FLAC3D模拟地下开采地表沉陷规律,分析开采沉陷对滑坡稳定性的影响。通过GeoStu-dio软件模拟降雨入渗下滑坡暂态渗流场,将计算得到的暂态孔隙水压力分布用于滑坡的极限平衡分析,并考虑基吸力对非饱和土抗剪强度的影响。探讨渗透系数、裂缝位置和深度对滑坡稳定性的影响。研究表明:降雨是诱发黄土层采动滑坡的主要因素,开采沉陷对采动滑坡稳定性的影响受控于采动区滑坡体结构形态、入渗能力、裂缝位置和深度。
Underground mining in China Western mine areas sometimes causes landslide disasters due to their location in mountain highland area.To attack this problem,FLAC3D was used to simulate the rule of surface subsidence caused by ground mining and to analyze the effect of surface subsidence on the stability of landslides.Transient seepage due to the descending of rainstorm infiltration was computed using the GeoStudio software.The computed transient pore water pressure was then used for limit equilibrium analyses of landslides.Effects of the suction on shear strength of unsaturated soils,and effects of coefficient of permeability,site and depth of the tension crack on landslide stability were discussed.The results show that rainfall is the major factor inducing mining landslide of soil layer,and the stability of landslides is dependent on the coefficient of permeability,the structure of landslide,the displacement and depth of tension crack of landslide.