基于Monte-Carlo法的尾矿库坝坡稳定可靠度分析

Reliability Analysis of Dam Slope Stability of Tailings Pond Based on Monte-Carlo Method

以南方某铀尾矿库坝坡为研究对象,在考虑坝体岩土参数不确定性和滑动面空间变异性基础上,采用GeoStudio软件的Slope模块,对坝坡敏感性及稳定可靠度进行了分析,得出坝体土的内摩擦角是影响坝坡稳定性的主要因素;利用Monte-Carlo法分析了坝坡稳定可靠度,并与定值分析法计算结果进行了对比。结果表明:定值分析法与Monte-Carlo法得到的坝体安全系数相同,坝坡在正常工况下失稳风险率仅为0.20%;在非常工况下坝坡失稳风险率为13.10%,坝坡稳定可靠性明显降低。相比定值分析法,Monte-Carlo法评价结论更加全面和直观,可为尾矿库坝坡治理方案优化和安全性评价提供参考。

Taking the dam slope of a uranium tailings pond in the southern China as an example,considering the uncertainty of the rock and soil parameters of the dam body and the spatial variability of the sliding surface,the slope module in the GeoStudio software was used to analyze the sensitivity and stability reliability of the dam slope.It is concluded that the internal friction angle of the dam body soil is the main factor affecting the stability of the dam slope.The Monte-Carlo method was used to analyze the reliability of the dam slope stability and compare it with the fixed value,the calculation results show that the safety factors obtained by these two methods are the same,the dam slope instability risk rate is 0.2%and 13.10%under normal and abnormal working conditions respectively.Compared with the fixed value analysis method,the Monte-Carlo method is more comprehensive and intuitive,which can provide a reference for the optimization of dam slope treatment scheme and safety evaluation of tailings pond.