露天矿山边坡破坏模式与稳定性的综合评价

以四川峨胜石灰石露天矿山为研究对象，在对矿山进行工程地质分区的基础上，采用赤平投影方法分析了各区工作台阶边坡、终了台阶边坡的破坏模式，并采用数值模拟方法分析了各区终了大边坡的破坏模式，在此基础上基于FLAC3D强度折减法对各区边坡的稳定性进行了综合评价。结果表明：①受结构面控制，工作台阶边坡与终了台阶边坡存在楔形体破坏、崩塌掉块、顺层滑移3种破坏模式；②受岩层控制，终了大边坡存在顺层滑移、滑移-拉裂、蠕滑-压致拉裂、塑流-拉裂4种破坏模式；③本研究中，顺向坡的二维模型稳定性系数大于三维模型，斜交坡三维模型稳定性系数大于二维模型，比值平均值为0.83。

COMPREHENSIVE EVALUATION OF SLOPE FAILURE MODE AND STABILITY OF OPEN-PIT MINE

Esheng open-pit mine of limestone in Sichuan province is taken as the study object, on the basis of the mine on engineering geological zoning, stereographic projection is used to analysis the failure modes of working bench slopes, ending stairs slopes, then numerical simulation method is used to analysis the failure modes of ending large slopes, finally the stability of the slopes of each area is evaluated based on the FLAC3D strength reduction method. The results show that: ① Under the control of discontinuities, there are 3 failure modes of working bench slopes and ending stairs slopes: wedge failure, collapse and bedding sliding.② Under the control of stratum, there are 4 failure modes of ending large slopes: bedding sliding, sliding-ripping, creeping-pressure induced ripping and flowing-ripping.③ in this study, for the dip slope, the stability coefficient of the two-dimensional model is larger than that of the three-dimensional model. As for the skew slopes, the result is just the opposite, and the average value of stability coefficient ratio of two dimensional and three dimensional model is 0.83.