贵州省六盘水水城高位远程滑坡流态化运动过程分析  

Analysis of the fluidization process of the high-position and longrunout landslide in Shuicheng,Liupanshui,Guizhou Province

作　　者：李壮 高杨[1,2] 贺凯[1,2] 高浩源 卫童瑶[3] 刘铮 赵志男 LI Zhuang;GAO Yang;HE Kai;GAO Haoyuan;WEI Tongyao;LIU Zheng;ZHAO Zhinan(Institute of Geomechanics,Chinese Academy of Geological Sciences,Beijing 100081,China;Key Laboratory of Neotectonic Movement and Geohazard,Beijing 100081,China;Chang′an University,Xi′an 710054,Shaanxi,China)

机构地区：[1]中国地质科学院地质力学研究所,北京100081 [2]新构造运动与地质灾害重点实验室,北京100081 [3]长安大学,陕西西安710054

出　　处：《地质力学学报》2020年第4期520-532,共13页Journal of Geomechanics

基　　金：国家重点研发计划项目(2018YFC1504806,2018YFC1504804);国家自然科学青年基金项目(41907257);中国地质科学院地质力学研究所基本科研业务费项目(DZLXJK201901);重庆市地质灾害自动化监测工程技术研究中心开放课题(KF2019-8)。

摘　　要：高位远程滑坡是中国西南山区常见的一类灾难性地质灾害,其发生往往伴随有碰撞解体效应,导致滑体碎裂化,转化为碎屑流或泥石流,具有流化运动堆积的特征。2019年7月23日发生于中国贵州省六盘水市水城县的鸡场镇滑坡是典型的高位远程流态化滑坡,滑坡前后缘高差430 m,水平运动距离1340 m,堆积体体积200×10^4m^3,导致21幢房屋被掩埋,51人遇难。基于野外详细调查和滑前滑后地形对比,采用DAN-W软件对水城滑坡的整个运动堆积过程进行了模拟,结果显示:水城滑坡在滑源区残留堆积体厚度最大为27 m,堆积区最大堆积厚度为15 m,滑坡碎屑流前缘最大运动速度为27 m/s,最大动能为6.57×10^6J;滑坡高位剪出,由于势能转化为动能,滑坡快速达到速度峰值,并铲刮地表松散土层;由于强降雨,滑体高速运动使基底孔隙水来不及排出,导致基底摩擦力下降,降低能量损耗,滑体解体促进颗粒流化运动,减少了摩擦,也是滑坡远程运动的重要原因。High-position and long-runout landslide is a kind of common geological disaster in the southwestern mountainous area of China.It always exists with impact disintegration effect,then converts to avalanche debris or debris flow with the characteristics of fluidization movement and accumulation.The Jichang landslide,occurred in Shuicheng County,Liupanshui City,Guizhou Province,China on July 23,2019,is a typical high-position and long-runout fluidized landslide.The position difference between toe and crown is 430 m,the horizontal movement distance is 1340 m,and the volume of accumulation body is 200×10^4 m^3,which caused 21 houses being buried and 51 people being killed.Based on the detailed field investigation and the comparison of the topography before and after the landslide,the whole process of the movement and accumulation of the landslide is simulated and analyzed by using DAN-W.(1)The maximum thickness of the accumulation body in the source area and accumulation area of the Shuicheng landslide is 27 m and 15 m respectively,the maximum velocity is 27 m/s in the front of debris flow,and the maximum kinetic energy is 6.57×10^6 J.(2)Due to the conversion of potential energy into kinetic energy,the landslide quickly reaches the peak velocity and scrapes the loose soil layer on the surface.(3)Due to heavy rainfall,the main body moves at high speed so that the pore water of the basement can’t be discharged in time,which leads to the decrease of the friction of the basement and reduces the energy loss;Disintegration of the main body promotes fluidization of particles,then reduces friction,which is also an important reason for the long-runout movement of landslide.

关 键 词：水城滑坡 高位远程 流态化 DAN-W 动力学特征 

分 类 号：P642.22[天文地球—工程地质学]