摘要
降雨是导致滑坡稳定性的主要因素之一,为探究不同降雨条件下非饱和土滑坡渗流变形及稳定性规律,基于饱和-非饱和渗流及强度折减法相关理论,以赣东某牵引式滑坡为研究对象,在勘查和室内试验的基础上,确定了滑坡隐患体岩土参数,用AutoCAD软件最大程度地还原了郑坊镇西山村童山组滑坡真实地形与地质条件,建立滑坡体渗流-变形耦合三维数学模型,并通过ABAQUS有限元软件,模拟不同降雨条件下(不同降雨强度、历时和降雨停雨后)非饱和土滑坡渗流变形及稳定性动态变化过程。结果表明:坡体表层孔隙水压力随降雨强度和历时的增大而逐渐升高,渗流速度逐渐增大,饱和区逐渐向非饱和区转化,位移变形表现为逐渐增大;降雨停雨后的滑坡隐患体渗流出现滞后现象,均匀性降雨后位移变形为先增大后减小,间断型降雨在短期停雨缓冲期下位移呈现出一定的周期性。对滑坡稳定性,不同降雨强度和历时下坡体强度折减稳定性系数的变化趋势相同,但同一降雨强度下的稳定性系数变化不同,总体趋势是随历时的增加而逐渐减小;降雨停雨后均匀型降雨坡体强度折减稳定性系数变化趋势是先下降后上升,间断型降雨坡体的稳定性则呈现出一定的周期性。
Rainfall is one of the main factors affecting landslide stability.To explore the deformation and stability laws of unsaturated soil landslides under different rainfall conditions,based on the theory of saturation-unsaturation and the intensity reduction method,focused on a traction landslide in eastern Jiangxi.The rock and soil parameters of the landslide hazard body were determined through field investigations and laboratory tests.AutoCAD software was used to restore the terrain and geological conditions of the Tongshan landslide in Xishan Village,Zhengfang Town,as accurately as possible.A three-dimensional mathematical model of seepagedeformation coupling for the landslide was established.The dynamic process of seepage deformation and stability of the unsaturated soil landslide under various rainfall conditions(different intensities,durations,and post-rain stoppage)was simulated.The results indicate that the pore water pressure at the slope surface increases gradually with rainfall intensity and duration.The drainage velocity increases,the saturated zone gradually transforms into the unsaturated zone,and the displacement and deformation increase progressively.After the rainfall stops,leakage in the landslide hazard body exhibits a delayed response.The displacement deformation after continuous rainfall first increases and then decreases,while the displacement following intermittent rainfall shows periodicity during the short-term post-rain stoppage period.In terms of landslide stability,the reduction trend of the stability coefficient of the slope body strength under different rainfall intensities and durations is similar,but the stability coefficient under the same intensity varies,with the overall trend showing a gradual decrease with increased duration.After the rain stopped,the stability coefficient of the uniform rainfall slope body decreases initially and then increases,whereas the stability of the intermittent rainfall slope body exhibits periodic variations.
作者
高小霞
查文华
齐新炬
许涛
纪超
GAO Xiao-xia;ZHA Wen-hua;QI Xin-ju;XU Tao;JI Chao(School of Civil and Architectural Engineering,East China University of Technology,Nanchang 330013,China;Geographic Information Engineering Brigade of Jiangxi Provincial Geological Bureau,Nanchang 330013,China)
出处
《科学技术与工程》
北大核心
2025年第20期8445-8454,共10页
Science Technology and Engineering
基金
江西省“双千计划”支持项目(DHSQT22021002)
江西省研究生创新项目(YC2021-B160)。
关键词
不同降雨条件
非饱和土滑坡
渗流-变形耦合
强度折减稳定性系数
数值模拟分析
different rainfall conditions
unsaturated soil landslide
seepage-deformation coupling
strength reduction stability coefficient
numerical simulation analysis
