西藏江达圭利大型深层滑坡蠕滑变形特征与稳定性分析  

Creeping deformation characteristics and stability analysis of Guili largedeep-seated landslide in Jiangda,Xizang

作　　者：刘吉鑫 郭长宝[1,3,4] 吴瑞安 宋德光[1] 闫怡秋 李祥 LIU Jixin;GUO Changbao;WU Ruian;SONG Deguang;YAN Yiqiu;LI Xiang(Institute of Geomechanics,Chinese Academy of Geological Sciences,Beijing 100081,China;Hefei University of Technology,Hefei 230009,Anhui,China;Key Laboratory of Active Tectonics and Geological Safety,Ministry of Natural Resources,Beijing 100081,China;College of Earth Science and Engineering,Shandong University of Science and Technology,Qingdao 266590,Shandong,China)

机构地区：[1]中国地质科学院地质力学研究所,北京100081 [2]合肥工业大学,安徽合肥230009 [3]自然资源部活动构造与地质安全重点实验室,北京100081 [4]山东科技大学地球科学与工程学院,山东青岛266590

出　　处：《地质通报》2024年第10期1855-1868,共14页Geological Bulletin of China

基　　金：中国地质调查局项目《川西-藏东地区交通廊道活动构造与地质调查》(编号:DD20190319);《全国重大工程地质安全风险区划与综合评价》(编号:DD20221816)。

摘　　要：青藏高原东缘地质环境条件复杂,在内外动力耦合作用下该区域发育一系列大型—特大型深层滑坡,曾多次发生滑坡失稳堵江事件。位于西藏江达县的圭利滑坡为一大型深层古滑坡,滑坡空间结构特征复杂、变形强烈。在收集并分析资料的基础上,综合利用野外地质调查、遥感解译、无人机航测、InSAR形变监测、数值模拟等研究方法,对圭利滑坡几何特征和蠕滑变形特征进行分析,并揭示其成因和失稳机制。研究结果表明,圭利滑坡在平面上可划分为滑坡后缘区(Ⅰ)和滑坡堆积区(Ⅱ)两部分,其中滑坡堆积区可划分为局部稳定区(Ⅱ_(1))和前缘强变形区(Ⅱ_(2)、Ⅱ_(3)),根据成都理工大学团队钻探数据,钻探揭露的深层滑带埋深分别为64.02 m、57.90 m、54.13 m,滑坡体积约6.55×10^(7)m^(3)。SBAS-InSAR监测数据表明,圭利滑坡目前处于蠕滑变形阶段,局部处于加速变形阶段,强烈变形区位于滑坡中前部,向后呈渐进变形破坏特征,地表最大形变速率可达−92.12 mm/a,滑坡体变形主要受降雨和河流侵蚀影响。数值模拟结果表明,天然工况下滑体位移变形量较小,稳定性较好;暴雨工况下圭利滑坡的前缘强变形区出现明显的变形迹象,可能发生失稳下滑,牵引后部堆积体发生滑动,为典型的牵引式蠕滑变形模式,下滑的堆积体可能堵塞金沙江,存在形成堵江−溃坝−洪水灾害链的风险。研究结果可为圭利滑坡防治提供有效参考,对大型深层滑坡稳定性评价具有一定理论和实际意义。The geological environment on the eastern edge of the Qinghai−Tibet Plateau is complex.Under the combined effects ofinternal and external forces,this region has witnessed the development of a series of large to super−large deep−seated landslides,leading to multiple instances of landslide−induced river blockages.The Guili landslide,located in Jiangda County,Xizang,is alarge−scale deep−seated landslide characterized by complex spatial structure and intense deformations.This study,based on data collection and analysis,comprehensively utilized research methods such as field geological surveys,remote sensing interpretation,unmanned aerial vehicle aerial surveys,InSAR deformation monitoring,and numerical simulation to analyze the geometric and creepdeformation characteristics of the Guili landslide and elucidate its origin and instability mechanism.In the view,it can be divided intotwo parts:the trailing edge of the landslide area(Ⅰ)and the landslide stacking area(Ⅱ).The landslide stacking area can be furtherdivided into a local stabilization zone(Ⅱ_(1))and a strongly deformed zone at the leading edge(Ⅱ_(2) and Ⅱ_(3)).The volume of the landslideis approximately 6.55×107 m3,with revealed depths of the deep slip zone from drilling being 64.02 m,57.90 m,and 54.13 m.Based onSBAS−InSAR monitoring data,the Guili landslide is currently in a stage of overall creeping deformation,with localized areasexperiencing accelerated deformation.The highly deformed zone at the front edge of the Guili landslide exhibits progressivedeformation and surface maximum deformation rate of up to−92.12 mm/a.Deformation of the landslide slope is primarily influencedby rainfall and river erosion.Numerical simulation results indicate that under natural conditions,the displacement and deformation ofthe sliding mass are relatively small,indicating good stability.However,under heavy rainfall conditions,the strong deformation zone atthe leading edge of the Guili landslide shows obvious signs of deformation,and may be destabiliz

关 键 词：青藏高原 圭利滑坡 流-固耦合 数值模拟 蠕滑变形 

分 类 号：P642.22[天文地球—工程地质学]