暴雨作用下含裂缝谭家湾堆积层滑坡渗流特征与稳定性分析  

Seepage Characteristics and Stability of Tanjiawan Accumulation Landslide with Cracks under Rainstorm

作　　者：李林均 简文星[1] 张端淼 董志鸿 张彬 潘永亮 LI Linjun;JIAN Wenxing;ZHANG Duanmiao;DONG Zhihong;ZHANG Bin;PAN Yongliang(Faculty of Engineering,China University of Geosciences(Wuhan),Wuhan 430074,China;Yichang Geological Environment Monitor Station,Yichang 443000,China;Hubei Institute ofMetallurgical Geology(Central South Institute of Metallurgical Geology),Yichang 443003;Emergency Center,Geological Environmental Center of Hubei Province,Wuhan 430034,China)

机构地区：[1]中国地质大学(武汉)工程学院,湖北武汉430074 [2]宜昌市地质环境监测站,湖北宜昌443000 [3]湖北冶金地质研究所(中南冶金地质研究所),湖北宜昌443003 [4]湖北省地质环境总站应急中心,湖北武汉430034

出　　处：《安全与环境工程》2021年第1期135-143,共9页Safety and Environmental Engineering

基　　金：国家自然科学基金项目(41272306);湖北省财政资金项目(YCZ0747-201901-01F)。

摘　　要：堆积层滑坡在三峡库区分布广泛,该类滑坡在前期变形过程中往往产生拉张裂缝,暴雨是导致其失稳的主要诱因之一。为探究暴雨作用下裂缝优势入渗对堆积层滑坡渗流场与稳定性的影响,以谭家湾堆积层滑坡为研究对象,通过地质调查、监测数据分析以及数值模拟方法,研究了暴雨作用下含裂缝谭家湾堆积层滑坡的渗流场与稳定性演化规律。结果表明:天然条件下谭家湾堆积层滑坡处于稳定状态,其变形与高强度降雨相关,地表位移曲线呈阶跃特征;当暴雨强度大于滑体饱和渗透系数后,雨水径流汇入裂缝形成积水并转变为有压入渗,增加了雨水的入渗速度与入渗量;当裂缝发育位置距地下水水位较近时,雨水通过裂缝易补给地下水,升高地下水水位,滑带在持续的浸泡软化作用下导致滑坡稳定性出现大幅度且持续性的降低。Accumulation landslides are widely distributed in the Three Gorges Reservoir area,and the early deformation of them often produces tensile cracks.Rainstorm is one of the major factors for instability of this type of landslide.In order to reveal the influence of crack dominant infiltration on the seepage field and stability of the accumulation landslide under the action of rainstorm,this paper takes Tanjiawan accumulation landslide as the research object,and uses the geological survey,monitoring data analysis and numerical simulation method to study the evolution law of seepage field and stability of the landslide with cracks under the influence of the rainstorm.The results show that Tanjiawan landslide is stable under natural conditions,its deformation is related to the high-intensity rainfall,and the displacement curve of the landslide is characterized by a stepped pattern;when the rainstorm intensity is greater than the saturated permeability coefficient of the soil,the rainwater runoff merges into the cracks and forms the ponding,which transforms into the pressure infiltration and greatly increases the infiltration speed and amount of the rainwater;when the position where the cracks are developed is close to the groundwater level,rainwater easily recharges groundwater through cracks,increase the groundwater level,and the continuous immersion and softening of the sliding zone leads to a large and continuous decrease in stability.

关 键 词：堆积层滑坡 暴雨入渗 拉张裂缝 渗流 稳定性 三峡库区 

分 类 号：X43[环境科学与工程—灾害防治] TU457[建筑科学—岩土工程]