摘要
滑坡/泥石流-堰塞湖-溃决洪水链生灾害是我国山丘区最为频繁的地质灾害,强降雨是其关键诱发因素。选取2020年四川省甘洛县黑西洛泥石流沟残留边坡开展现场人工降雨试验。通过分析强降雨作用下边坡孔隙水压力和土壤含水率的变化规律,并结合X射线能谱分析(EDS)测试结果,探究降雨对边坡稳定性的影响。试验结果表明:孔隙水压力和土壤含水率在降雨过程中会明显上升,随着降雨的持续进行,边坡的侵蚀破坏范围逐渐扩大,破坏过程中伴随着土壤含水率和孔隙水压力的增大,并且相应位置的土壤含水率和孔隙水压力变化一致;EDS测试结果表明边坡土体中含有伊利石和高岭石两类黏土矿物,降雨会导致边坡表层土体膨胀软化,土颗粒的黏聚力降低,坡面产生拉裂缝,边坡强度降低,最终发生冲刷和侵蚀破坏。试验结果为揭示降雨作用下边坡侵蚀破坏的发生规律提供重要的理论指导。
Landslide/debris flow,dammed barrier lake,and subsequent dam-break floods constitute the most frequent geological disasters in mountainous regions,with heavy rainfall serving as the critical inducing factor.In 2020,artificial rainfall field tests were carried out on the residual slope of a debris flow in Hexiluo gully,Ganluo County,Sichuan Province.The study investigated the impact of rainfall on slope stability through analysis of variations in soil moisture content,pore water pressure under heavy rainfall,and X-ray energy dispersive spectroscopy(EDS)test results.Results indicate that pore water pressure and soil moisture content increase significantly during rainfall.As rainfall persists,the extent of slope erosion and failure widens.Concurrently,soil moisture content and pore water pressure increase during slope failure,with consistent patterns observed in both parameters.The result of EDS tests reveal the presence of illite and kaolinite clay minerals in slope soil.Rainfall induces surface soil expansion and softening,reduces soil particle cohesion,causes tension cracks on the slope surface,weakens slope stability,and ultimately leads to erosion and failure.The research results contribute theoretically to understanding the patterns of slope erosion and failure induced by rainfall.
作者
吕霞
范刚
刘大瑞
林子钰
LYU Xia;FAN Gang;LIU Darui;LIN Ziyu(College of Water Resource&Hydropower,Sichuan University,Chengdu,Sichuan 610065,China)
出处
《中国地质灾害与防治学报》
CSCD
2024年第6期82-89,共8页
The Chinese Journal of Geological Hazard and Control
基金
国家自然科学基金区域创新发展联合基金(西藏)项目(U20A20111)。
关键词
现场试验
降雨入渗
灾害链
滑坡
强降雨
field test
rainfall infiltration
chain disaster
landslide
heavy rainfall
作者简介
第一作者:吕霞(1999-),女,重庆人,硕士生,研究方向为滑坡/泥石流-堰塞湖-溃决灾害链。E-mail:lvxia76@stu.scu.edu.cn;通讯作者:范刚(1987-),男,博士,副教授,研究方向为滑坡灾害防治机理。E-mail:fangang@scu.edu.cn。
