摘要
降雨诱发堆积体边坡失稳破坏是一种较为突出的滑坡灾害形式,近些年随着强降雨天气频率增大,诱发的堆积体滑坡问题尤为突出。围绕堆积体边坡在强降雨下的破坏机制,开展相关研究,探究了不同基质含量以及含石量分布对于堆积体边坡破坏模式的影响规律。首先,通过室内大三轴试验确定堆积体边坡试样在固定黏土含量10%,碎石含量分别为30%、50%、70%下的应力-应变关系;随后,开展降雨诱发堆积体滑坡的模型试验,研究强降雨条件下不同级配堆积体边坡的失稳破坏模式,分析坡顶位移以及堆积体内部含水率、土压力、孔隙水压力的变化规律,阐明堆积体不同部位细粒含量变化及细颗粒竖向迁徙过程;最终,揭示降雨诱发不同含石量堆积体边坡的失稳与破坏机制,相关成果能为堆积体滑坡的预警提供科学的理论依据。
Rainfall-induced accumulation landslide is one of the most widespread geo-hazards.In recent years,due to more extreme rainfall events brought on by climate change,the scale and frequency of the rainfall-induced accumulation landslides have further increased.Centering on the slope failure mechanisms due to the extreme rainfalls,this research carries out a series of model tests in order to explore the influence of different gradations of the slope materials on the slope failure mechanism.A series of large-scale triaxial tests is carried out first,where three different colluvium materials are remolded,with the clay content fixed at 10%and the rock contents at 30%,50%,and 70%,respectively,so that stress-strain relationships of the samples considering different gradations can be obtained.Thereafter,three slope models are built,consisting of the designed gradations.Extreme rainfalls are then applied to cause the slopes to fail,aiming to reveal different slope failure modes.Meanwhile,the changes of the water content,soil pressure,and pore water pressure inside the slope during the slope failure process are also monitored and analyzed,and the changes of fines content and its moving trajectories during the rainfall infiltration process are also illustrated.Finally,the failure mechanism of the accumulation landslide under extreme rainfall is summarized,which can hopefully provide some theoretical basis for the early warning of the accumulation landslide.
作者
王斌
李洁涛
王佳俊
陈鹏林
WANG Bin;LI Jie-tao;WANG Jia-jun;CHEN Peng-lin(State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan,Hubei 430071,China;School of Engineering Sciences,University of Chinese Academy of Sciences,Beijing 100049,China;School of Engineering,China University of Geosciences(Wuhan),Wuhan,Hubei 430074,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2023年第S01期234-248,共15页
Rock and Soil Mechanics
基金
国家自然科学基金项目(No.51979270,No.51709258)
中国科学院青年人才引进项目。
关键词
堆积体
滑坡
降雨
土体基质
含石量
模型试验
accumulation
landslide
rainfall
soil matrix
rock content
model test
