动水压力型滑坡不利因素组合及作用机制试验研究  

Experimental research on adverse factors combination and action mechanism of seepage-driven landslide

作　　者：陈勇[1,2] 叶润青 申清峰 王力 CHEN Yong;YE Runqing;SHEN Qingfeng;WANG Li(Key Laboratory of Geological Hazards on Three Gorges Reservoir Area,China Three Gorges University,Yichang 443002,China;Geological Science and Technology Innovation Center of Central South China,Wuhan 430070,China)

机构地区：[1]三峡大学三峡库区地质灾害教育部重点实验室,湖北宜昌443002 [2]中南地质科技创新中心,湖北武汉430070

出　　处：《自然灾害学报》2025年第1期75-84,共10页Journal of Natural Disasters

基　　金：国家自然科学基金面上项目(42272317);国家自然科学基金区域发展联合基金重点项目(U21A2031)。

摘　　要：因库水位下降而变形失稳的动水压力型滑坡,是库区多见的一种滑坡类型,且不同滑坡对水位下降的响应存在巨大差异。为探索动水压力型滑坡的失稳特征和诱发机制,基于不同影响因素的作用特点分析,开展了多组模型试验,揭示了滑面形态、滑体渗透系数和水位骤降速率对滑坡孔隙水压力、体积含水率及变形破坏全过程的影响规律。研究结果表明,多影响因素组合对动水压力型滑坡不利程度的排序,并总结了其变形失稳的主控因素、次生因素和诱发因素,发现了直线形滑面的滑坡失稳特征为浅层滑动诱发滑体逐层剥离的牵引式破坏、弧线形滑面的滑坡失稳特征为坡脚垮塌逐渐向后溯源的牵引式破坏,二者差异的内在机制是滑体厚度不同导致渗透压力的具体作用区域和持续时间显著不同。A seepage-driven landslide is a common type of landslide in a reservoir area,it is deformed and unstable owing to the drawdown of reservoir water level.However,the response of different landslides to water level drawdown is significantly different.To understand the instability characteristics and inducing mechanism of seepage-driven landslide,multiple model tests were conducted based on the analysis of the action characteristics of different influencing factors.This study found that the effects of sliding surface morphology,the permeability coefficient of sliding mass and the rate of water level drawdown on the pore water pressure,volumetric water content and the whole process of deformation and failure are significant.The results can be summarized as follows:the order of the adverse degree of multi-factor combination to seepage-driven landslide was clarified,then the main control factors,derivative factors and inducement factors to landslide deformation and failure were summarized.It is discovered that the slide instability characteristic of a straight-line sliding surface is retrogressive failure induced by shallow sliding.Conversely,the landslide instability characteristic of an arc-line sliding surface is retrogressive failure of the slope toe collapse,which gradually traces back.The internal mechanism of the difference between these two landslides is that the different thickness of the sliding mass leads to the different position and duration of the seepage water pressure.

关 键 词：动水压力型滑坡 模型试验 水位下降 失稳特征 滑面形态 

分 类 号：P642.22[天文地球—工程地质学] P694[天文地球—地质矿产勘探] X141[天文地球—地质学]