摘要
黄土填方边坡在降雨入渗下容易发生滑坡。为了探讨降雨入渗下压实度对黄土填方边坡变形破坏机制、失稳模式以及滑动机理的影响,基于室内降雨系统,结合传感器监测和三维激光扫描技术,开展了边坡压实度为80%(低压实度)、90%(中压实度)、95%(高压实度)的降雨模型试验研究,分析了压实度对填方边坡体积含水率、基质吸力以及变形破坏过程的影响规律。结果表明:压实度的不同,边坡首先破坏的位置不一。中、高压实度下的边坡最先破坏发生在坡脚处,表现出滑塌破坏;而低压实度则是在坡顶,为湿陷沉降破坏。边坡压实度越大,其变形破坏过程持续时间越长,所需累积雨量就越大,但滑动距离和滑面深度越小。随压实度的增加,边坡破坏模式由深层整体破坏向浅层多级破坏转变。低压实度边坡为湿陷沉降-深层蠕滑拉裂式,中压实度边坡为深层蠕滑拉裂式破坏,而高压实度边坡则为浅层多级后退式失稳。
Loess fill slope is prone to landslide under the condition of rainfall infiltration.The influence of compaction degree under rainfall infiltration on the deformation and failure mechanism and the instability mode and sliding mechanism of loess fill slope is explored.Based on the indoor rainfall system,combined with the sensor monitoring and 3 D laser scanning technology,the rainfall model tests with slope compaction of 80%(low pressure compaction),90%(medium compaction)and 95%(high pressure compaction)are carried out.The influence of compaction degree on the volume moisture content,matrix suction and deformation failure process of fill slope is analyzed.The results show that the first failure position of the slope is different with different compactness.The first failure of the slope under the medium and high compactness occurs at the foot of the slope,showing the collapse failure.However,the low degree of compaction is at the top of the slope,which is collapsible.The greater the compactness of the slope,the longer the duration of the deformation and failure process,and the more accumulated rainfall required,but the smaller the sliding distance and sliding surface depth.With the increase of compactness,the failure mode of the slope changes from deep overall failure to shallow multi-stage failure.The low-pressure compaction slope is of the collapsible settlement deep creep tensile failure,the medium compaction slope is of the deep creep tensile failure,and the high-pressure compaction slope is of the shallow multi-stage backward failure.
作者
陈林万
裴向军
张晓超
张硕
钟玉健
罗欣
CHEN Linwan;PEI Xiangjun;ZHANG Xiaochao;ZHANG Shuo;ZHONG Yujian;LUO Xin(State Key Laboratory of Geohazard Prevention and Geoenvironmental Protection,Chengdu University of Technology,Chengdu,Sichuan 610059,China;College of Environment and Civil Engineering,Chengdu University of Technology,Chengdu,Sichuan 610059,China;College of Ecological Environment,Chengdu University of Technology,Chengdu,Sichuan 610059,China;College of Geosciences and Engineering,North China University of Water Resources and Electric Power,Zhengzhou,Henan 450045,China)
出处
《水文地质工程地质》
CAS
CSCD
北大核心
2022年第2期137-147,共11页
Hydrogeology & Engineering Geology
基金
国家自然科学基金项目(41790445)
国家重点研发计划(2018YFC1504702)。