斜里滑坡体稳定性评价及对坝址选择影响分析  

Stability Evaluation of Xieli Landslide and Analysis of Its Impact on Dam Site Selection

作　　者：姚纪华 伍佑伦 刘亚玲 宋文杰 Yao Jihua;Wu Youlun;Liu Yaling;Song Wenjie(Hunan Institute of Water Resources and Hydropower Research;Hunan Jiuyi Engineering Design Co.,Ltd.)

机构地区：[1]湖南省水利水电科学研究院,长沙市410007 [2]湖南九一工程设计有限公司,长沙市410018

出　　处：《勘察科学技术》2023年第4期16-20,49,共6页Site Investigation Science and Technology

基　　金：长沙市自然科学基金项目(kq2202358);湖南省重大水利科技项目(XSKJ2021000-09);湖南省水利水电科学研究院优秀人才培养支撑项目(2021-11)。

摘　　要：斜里滑坡体位于某水库下坝址近坝库内,规模较大,一旦失稳,必将危及整个大坝安全,甚至造成溃坝,滑坡体的稳定性及其影响成为坝址选址的控制性因素。该文基于滑坡体地质特性研究和折线形滑动面极限平衡法,获得滑坡体建库前天然和暴雨两种工况下的稳定安全系数,并与滑坡体长期实测变形监测成果进行对比分析,修正滑体、滑带物理力学参数,计算建库蓄水后多种工况下滑坡体稳定性,分析其工程影响,为坝址选择提供有力依据。研究表明:折线形滑动面极限平衡法计算滑坡体稳定性是可行的;蓄水前滑坡体在天然和暴雨两种工况下处于基本稳定;蓄水后在正常蓄水位和正常蓄水位+地震两种工况下也处于基本稳定,但库水位骤降工况下处于不稳定;坝址选择应尽量避开该滑坡体。The Xieli landslide is located near the lower dam site of a reservoir.It has a large scale.Once instability occurs,the safety of the entire dam will be endangered and even cause dam break.The stability of landslide and its influence become the controlling factors of dam site selection.Based on the study of geological characteristics of landslide mass and the limit equilibrium method of broken-line sliding surface,the stability safety factor of landslide mass under natural and rainstorm conditions before reservoir construction is obtained.And compared the factor with the long-term measured deformation monitoring results of landslide mass,the physical and mechanical parameters of landslide mass and landslide belt are corrected,the stability of landslide mass under various conditions after reservoir construction and impoundment are calculated,and its engineering impact is analyzed,providing a strong basis for dam site selection.The research shows that it is feasible to calculate the stability of landslide mass by the limit equilibrium method of broken-line sliding surface;The landslide mass is basically stable under natural and rainstorm conditions before impoundment;it is also basically stable under the two working conditions of normal pool level and normal pool level+earthquake after impoundment,but it is unstable under the condition of sudden drop of the reservoir water level;the dam site should be selected to avoid the landslide mass as much as possible.

关 键 词：滑坡体 稳定性 坝址选择 位移监测 折线形滑动面极限平衡法 稳定安全系数 

分 类 号：P642.22[天文地球—工程地质学] TV64[天文地球—地质矿产勘探]