西部高山峡谷区重大滑坡成生规律及灾变演化机理研究进展  

Formation and catastrophic evolution of giant landslides in the alpine canyon area of western China

作　　者：张世殊 胡新丽[2] 章广成[2] 李亚博 刘欣宇 徐庆尧 冉从彦 赵小平 ZHANG Shishu;HU Xinli;ZHANG Guangcheng;LI Yabo;LIU Xinyu;XU Qingyao;RAN Congyan;ZHAO Xiaoping(PowerChina Chengdu Engineering Corporation Limited,Chengdu 610072,Sichuan,China;Faculty of Engineering,China University of Geosciences(Wuhan),Wuhan 430074,Hubei,China)

机构地区：[1]中国电建集团成都勘测设计研究院有限公司,四川成都610072 [2]中国地质大学(武汉)工程学院,湖北武汉430074

出　　处：《地质力学学报》2024年第5期795-810,共16页Journal of Geomechanics

基　　金：国家自然科学基金项目(U22A20601)。

摘　　要：中国西部水电工程大多位于高山峡谷内,复杂的工程地质条件导致峡谷库岸滑坡灾害分布广泛。基于西部高山峡谷水电工程区的工程地质特征,系统分析了地形、地质构造、滑体物质、坡体结构和水文地质条件与滑坡的成生发育关系,并总结了典型滑坡的类型、特征及其灾变演化的力学机制。研究结果表明:西部高山峡谷滑坡以坡度30°~50°、高程超过1000 m、体积超过100×10^(4)m^(3)的滑坡为主;三叠系、奥陶系和志留系为典型的易滑地层;降雨和水库蓄水导致侵蚀基准面抬升、侵蚀范围扩大,库区水位的反复升降导致涉水滑坡体前缘岩土体性质降低。西部高山峡谷区滑坡类型主要分为以牵引式滑坡、推移式滑坡和复合式滑坡为主的堆积层滑坡以及以顺层岩质滑坡、溃屈型岩质滑坡、反倾岩质滑坡和座落式滑坡为主的岩质滑坡,不同类型的滑坡其演化过程不同,滑坡灾变机理也有所差异。研究成果将对西部高山峡谷区的滑坡识别、监测、预警以及防治具有一定的指导意义。[Objective]Most hydroelectric projects in western China are located in alpine canyons.The intricate geological engineering conditions in this area have contributed to the widespread distribution of landslide disasters across the reservoir banks of hydroelectric projects.[Methods]Based on the engineering geological characteristics of western alpine canyons,correlations between topography,geological structure,landslide material,slope structure,hydrogeological conditions,and the formation and progression of landslides were analyzed.We also delineated the types and features of landslide development in the western region,as well as the mechanisms governing the evolution of typical landslide disasters.[Results]Results indicate that the landslides were characterized by slopes ranging from 30°to 50°,elevations exceeding 1000 m,and volumes surpassing one million cubic meters.Triassic,Ordovician,and Silurian strata were identified as the principal slippery strata in this area.Rainfall and reservoir impoundment significantly influenced landslide stability,leading to erosion,datum uplift,and range expansion.Water level fluctuations resulted in diminished rock and soil properties along the leading edge of advancing landslides.[Conclusion]The most frequent landslides in the western alpine region included accumulated landslides dominated by traction,thrust,and composite mechanisms and rock landslides dominated by bedding,buckling,anti-dip,and seating mechanisms.[Significance]This study elucidates landslide disaster mechanisms under varying evolutionary and mechanical failure processes,providing significant guidance for the identification,monitoring,early warning,and prevention of landslide disasters in the western region.

关 键 词：西部高山峡谷区 库岸滑坡 成生规律 滑坡类型 演化机理 破坏力学机制 

分 类 号：P642.22[天文地球—工程地质学]