基于改进传递系数法苗家坝刘家滑坡稳定性研究及敏感性分析

Stability Study and Sensitivity Analysis of Liujia Landslide in Miaojiaba Based on Improved Transfer Coefficient Method

在极限平衡理论基础上对传递系数法进行改进,再结合滑坡现场勘探和室内资料整理分析进行计算参数取值,对苗家坝刘家滑坡不同工况的稳定性进行定量计算,并分析改进系数法的可行性.结果表明:改进传递系数法计算的稳定系数比传递系数法计算出的稳定系数小0.003 3~0.014 5,改进传递系数法计算出的剩余下滑力是传递系数法计算出的K倍(K为安全系数).基于改进传递系数法计算的稳定性系数,使用内摩擦角φ、黏聚力c、重度γ对稳定性系数进行敏感性分析.结果表明:内摩擦角φ、黏聚力c与稳定性系数呈线性正相关,重度γ与稳定性系数呈线性负相关;三个因素敏感度排序S_(φ)>S_(γ)>S_(c).运用定性分析与定量计算相结合的方法综合分析滑坡的稳定性及影响滑坡稳定性的因素.

This article improves the transfer coefficient method on the basis of the limit equilibrium theory,and then combines the landslide field exploration and indoor data analysis to calculate the parameter values.The stability of the Liujia landslide in Miaojiaba under different conditions is quantitatively calculated.The feasibility of the improved coefficient method is analyzed.The results show that the stability coefficient calculated by the improved transfer coefficient method is 0.0033-0.0145 smaller than the stability coefficient calculated by the transfer coefficient method,and the remaining sliding force calculated by the improved transfer coefficient method is K times of that calculated by the transfer coefficient method(K is the safety factor).Based on the stability coefficient calculated by the improved transfer coefficient method,the internal friction angle φ,the cohesion force c,and the severityγare used for sensitivity analysis of the stability coefficient.It shows that the internal friction angleφand the cohesion force c are linearly positively correlated with the stability coefficient,and the severity is linearly negatively correlated with the stability coefficient;the sensitivity of the three factors is ranked as follows:S_(φ)>S_(γ)>S_(c).The method of combining qualitative analysis and quantitative calculation is used to comprehensively analyze the stability of the landslide and the factors affecting the stability of the landslide.