西露天矿边坡失稳影响因素分析  

Analysis on the Influence Factors of Slope Instability in West Open-pit Mine

作　　者：王瑞鹏 王金安[1,2] WANG Ruipeng;WANG Jin'an(School of Civil and Resource Engineering,University of Science and Technology Beijing,Beijing 100083,China;State Key Laboratory of Ministry of Education for Efficient Minim and Safety of Metal Mines,Beijing 100083,China)

机构地区：[1]北京科技大学土木与资源工程学院,北京100083 [2]金属矿山高效开采与安全教育部重点实验室,北京100083

出　　处：《矿业研究与开发》2022年第1期64-70,共7页Mining Research and Development

基　　金：国家重点研发计划项目(2017YFC1503104)。

摘　　要：针对西露天矿长年开采、矿震影响造成的边坡滑坡失稳现象,引入安全系统工程中的事故树分析方法,通过现场踏勘和资料调研,构建西露天矿边坡失稳的事故树模型。研究表明:能够引起边坡失稳的最小割集有132个、不发生失稳的最小径集有2个,边坡失稳的概率极大。在20个基本事件中,雨水、循环冻融和软弱夹层的存在是边坡失稳的关键因素,结合数值分析发现软弱夹层在强度软化过程中,边坡可能出现沿上、下不同软弱夹层产生失稳,其边坡稳定性尤其对上软弱夹层的内摩擦角十分敏感。雨水入渗边坡的过程中,边坡表面的基质吸力、体积含水率不断增大,导致表面容重增大,同时水对岩石的软化作用均不利于边坡稳定,相关结论可供露天边坡灾害治理参考。Aiming at the instability of slope landslide caused by long-term mining and mine earthquake in West Open-pit Mine, the fault tree analysis method in safety system engineering was introduced. Then, through field survey and data investigation, the fault tree model of slope instability in West Open-pit Mine was constructed. The study shows that there are 132 minimum cut sets that can cause slope instability and 2 minimum diameter sets that do not cause slope instability. The probability of slope instability is very high. In the 20 basic events, the rainwater, the cyclic freezing and thawing, as well as the weak interlayer are the key factors of slope instability. Combined with numerical analysis, it is found that in the strength softening process of weak interlayer, the slope may be unstable along the upper and lower weak interlayer, and the slope stability is particularly sensitive to the internal friction angle of the upper weak interlayer. In the process of rainwater infiltration into the slope, the matrix suction and the volume moisture content on the slope surface are increasing, resulting in the increase of surface bulk density. At the same time, the softening effect of water on rock is not conducive to slope stability. The relevant conclusions can be used as references for the disaster treatment of open-pit slope.

关 键 词：露天矿 事故树模型 边坡失稳 软弱夹层 降雨 

分 类 号：TD824.7[矿业工程—煤矿开采]