金沙江上游沙东滑坡发育特征与堵江溃决预测分析  

Development characteristics and river blocking outburst analysis of Shadong landslide in the upper reaches of Jinsha River

作　　者：郑顺祥 王军 鄢勇 刘文 赵恒 杨钧翔 范雄安 张毅 王猛 余天彬 ZHENG Shunxiang;WANG Jun;YAN Yong;LIU Wen;ZHAO Heng;YANG Junxiang;FAN Xiongan;ZHANG Yi;WANG Meng;YU Tianbin(Huadian Jinsha River Upstream Hydropower Development Co.Ltd.,Chengdu,Sichuan 610095,China;Sichuan Institute of Comprehensive Geological Survey(Evaluation and Utilization of Strategic Rare Metals and Rare Earth Resource Key Laboratory of Sichuan Province),Chengdu,Sichuan 610081,China;Yebatan Branch of Huadian Jinsha River Upstream Hydropower Development Co.Ltd.,Ganzi,Sichuan 627153,China;Batang(Lawa)Branch of Huadian Jinsha River Upstream Hydropower Development Co.Ltd.,Ganzi,Sichuan 627650,China)

机构地区：[1]华电金沙江上游水电开发有限公司,四川成都610095 [2]四川省综合地质调查研究所(稀有稀土战略资源评价与利用四川省重点实验室),四川成都610081 [3]华电金沙江上游水电开发有限公司叶巴滩分公司,四川甘孜627153 [4]华电金沙江上游水电开发有限公司巴塘(拉哇)分公司,四川甘孜627650

出　　处：《水文地质工程地质》2024年第6期160-170,共11页Hydrogeology & Engineering Geology

基　　金：四川省地质调查研究院财政资金项目(SCIGS-CZDXM-2024006);华电金沙江上游水电开发有限公司科研项目(JS-LW-FW/ZX-084,JS-YBT-FW/YF-2022-30);部-省合作四川地质灾害遥感项目(SCDZRS-2023)。

摘　　要：沙东滑坡位于金沙江结合带内,复活变形迹象明显,极可能形成滑坡-堵江-洪水灾害链,严重威胁沿线重大工程建设、交通设施以及人民生命财产安全。采用多源遥感动态监测、工程地质调查、数值模拟等方法,分析滑坡的复活变形特征,探讨滑坡堵江溃决的危险性。结果表明:沙东滑坡为巨型滑坡,体积约23045×10^(4) m^(3),目前处于蠕滑变形阶段,2018—2023年存在持续变形,滑坡变形区主要集中在斜坡前缘,下游侧变形比上游侧强烈。沙东滑坡沿基覆界面滑动,表现为牵引式渐进破坏,在稳定性分析的基础上,建立了3种潜在失稳模式:①天然工况下,C3次级滑体前缘失稳,滑坡持续过程约35 s,滑体最大速度达30 m/s,堵江堰塞坝高度约90 m,堰塞湖库容约1.62×10^(8) m^(3),堰塞坝溃决后拉哇电站坝址处最大洪水流量约3535 m^(3)/s,最大洪峰高度约14 m;②暴雨工况下,Ⅱ-2区失稳,堵江堰塞坝高度约133 m,堰塞湖库容约4.10×10^(8) m^(3),堰塞坝溃决后拉哇电站坝址处最大洪水流量约11315 m^(3)/s,最大洪峰高度约31 m;③暴雨+地震工况下,Ⅱ-1、Ⅱ-2区同时失稳,堵江堰塞坝高度约153 m,堰塞湖库容约5.66×10^(8) m^(3),堰塞坝溃决后拉哇电站坝址处最大洪水流量约19960 m^(3)/s,最大洪峰高度约45 m。沙东滑坡堵江风险高、致灾性强,建议采用天-空-地-内一体化的手段进行持续监测,研究滑坡的预警阈值,精准管控重大地质灾害风险。The Shadong landslide,located in the Jinsha suture belt,exhibits significant signs of deformation.It is a high risk of developing into a disaster chain of landslide,river blockage,and flood,posing a serious threat to major engineering construction,transportation facilities,and people's lives and property.In this study,multi-source remote sensing dynamic monitoring,engineering geological survey,and numerical simulation were used to analyze the deformation characteristics and explore the risk of river blocking outburst of the Shadong landslide.The results show that the Shadong landslide is a giant landslide with a volume of approximately 23045×10^(4) m^(3).The landslide is currently in the stage of creep deformation,with continuous deformation from 2018 to 2023.The reactivation deformation area of the landslide is mainly concentrated at the front edge of the slope,and the deformation on the downstream side is stronger than that on the upstream side.The Shadong landslide slides along the bedrock cover interface,exhibiting a traction type progressive failure.Based on stability analysis,three potential instability modes have been established.Under natural conditions,the leading edge of the secondary landslide C3 is unstable,with the landslide event lasting around 35 seconds.The maximum speed of the landslide reaches 30 m/s.The height of the barrier dam is about 90 m,and the barrier lake capacity is about 1.62×10^(8) m^(3),with a maximum flood flow of approximately 3535 m^(3)/s and a flood peak height of approximately 14 m at the dam site of the Lava Power Station after the barrier dam failure.Under storm conditions,instability occurs in zone II-2,forming a 133-meter-high barrier dam with a lake capacity of approximately 4.10×10^(8) m^(3).The maximum flood flow could reach 11315 m^(3)/s,with a maximum flood peak height of approximately 31 m at the Lava Power Station.In the event of both storm and earthquake conditions,II-1 and II-2 zone are unstable at the same time,resulting in the height of the barrier dam of appr

关 键 词：发育特征 堵江溃决 金沙江上游 沙东滑坡 

分 类 号：P642.22[天文地球—工程地质学]