地震对金沙江金坪子滑坡的稳定性影响分析  

Analysis of the Effect of Earthquake on the Stability of Jinpingzi Landslide on the Jinsha River

作　　者：王涛[1] 周葵 袁乾博 肖诗荣[1] WANG Tao;ZHOU Kui;YUAN Qianbo;XIAO Shirong(College of Civil Engineering&Architecture,China Three Gorges Univ.,Yichang 443002,China;State Grid Xingshan Electric Power Supply Company,Yichang 443700,China)

机构地区：[1]三峡大学土木与建筑学院,湖北宜昌443002 [2]国家电网湖北省电力有限公司兴山县供电公司,湖北宜昌443700

出　　处：《三峡大学学报（自然科学版）》2021年第1期31-37,共7页Journal of China Three Gorges University：Natural Sciences

基　　金：国家自然科学基金(41272310)。

摘　　要：金沙江乌东德水电站金坪子滑坡的稳定性对于该水电站的安全运行具有重要意义.为探究地震作用对金坪子滑坡体稳定性的影响,以金坪子滑坡Ⅱ区为例,在滑坡地质模型研究的基础上,运用极限平衡法及动力时程分析法,通过研究滑坡稳定性系数以及滑坡位移、速度、加速度曲线变化,综合研究了滑坡体在天然与加速度峰值为0.1g地震两种状态下的稳定性.分析表明:地震作用下坡体安全系数小于0.8,证明坡体在遭遇地震时可能发生失稳;坡体对地震作用的响应存在一个高程放大效应,坡体变形强度随高程增加而增大;经计算,地震变形峰值发生在6 s时刻,滑坡体最终永久变形位移达26 cm;地震作用下坡体变形的振幅呈循环往复变化,导致坡体内惯性力呈往返运动,降低了岩土体之间摩擦力导致产生的弧形破坏,同时在运动过程中为地下水渗入提供了路径,降低了坡体的稳定性.本文分析成果对研究同类坡体变形具有一定借鉴意义.The stability of the Jinpingzi landslide at Wudongde Hydropower Station on the Jinsha River is of great significance to the safe operation of the hydropower station.In order to explore the influence of earthquake on the stability of Jinpingzi landslide,this paper takes Jinpingzi landslide area II as an example.Based on the study of landslide geological model,limit equilibrium method and dynamic time history analysis method were used to study landslide stability.The stability of the landslide body under the natural and acceleration peaks of 0.1g earthquakes was comprehensively studied.The analysis shows that the safety factor of the slope under earthquake action is less than 0.8,which proves that the slope body may be unstable when encountering an earthquake;there is an elevation amplification effect in the response of the slope body to the earthquake action,and the deformation strength of the slope body increases with the increase of elevation;According to calculations,the seismic deformation peak occurs at 6 s,and the final permanent deformation displacement of the landslide body reaches 26 cm;The amplitude of the deformation of the slope changes in a cyclic way,which leads to the reciprocating motion of the inertial force in the slope,and reduces the friction between the rock and soil,resulting in the arc failure;and at the same time generates a path for groundwater infiltration during the movement,reducing the stability of the slope.The analysis results of this paper have certain reference significance for the study of similar slope deformation.

关 键 词：地震作用 金坪子滑坡Ⅱ区 极限平衡法 动力时程分析法 高程放大效应 

分 类 号：P642.22[天文地球—工程地质学] TU435[天文地球—地质矿产勘探]