ISSN 1000-3665 CN 11-2202/P
    石子健,陈稳,盛逸凡,等. 碎屑流滑坡变形及运动特征研究−以恩施市沙子坝滑坡为例[J]. 水文地质工程地质,2024,51(0): 1-11. DOI: 10.16030/j.cnki.issn.1000-3665.202306033
    引用本文: 石子健,陈稳,盛逸凡,等. 碎屑流滑坡变形及运动特征研究−以恩施市沙子坝滑坡为例[J]. 水文地质工程地质,2024,51(0): 1-11. DOI: 10.16030/j.cnki.issn.1000-3665.202306033
    SHI Zijian, CHEN Wen, SHENG Yifan, et al. Deformation and movement characteristics of debris flow landslide: A case study of the shaziba landslide in Enshi, China[J]. Hydrogeology & Engineering Geology, 2024, 51(0): 1-11. DOI: 10.16030/j.cnki.issn.1000-3665.202306033
    Citation: SHI Zijian, CHEN Wen, SHENG Yifan, et al. Deformation and movement characteristics of debris flow landslide: A case study of the shaziba landslide in Enshi, China[J]. Hydrogeology & Engineering Geology, 2024, 51(0): 1-11. DOI: 10.16030/j.cnki.issn.1000-3665.202306033

    碎屑流滑坡变形及运动特征研究以恩施市沙子坝滑坡为例

    Deformation and movement characteristics of debris flow landslide: A case study of the shaziba landslide in Enshi, China

    • 摘要: 碎屑流滑坡往往表现出高滑动速度以及远距离滑移等运动学特征,并且其失稳滑动易对周边造成严重的破坏和巨大的财产损失。2020年7月21日,在特大暴雨的持续影响下,恩施沙子坝滑坡失稳滑动并发展为碎屑流滑坡,最终在清江内堆积并形成堰塞湖。为了探究沙子坝滑坡滑动过程所表现的速度和位移等运动特征以及滑体的运动演化规律,通过处理高精度的无人机正射影像的方法来构建滑坡三维数值模型,并基于室内试验获取的滑体力学性质对模型细观参数进行标定,最后,使用颗粒流PFC3D(Particle Flow Code)软件模拟沙子坝碎屑流滑坡的从滑动到堆积的过程。通过沙子坝滑坡模拟可得:沙子坝滑坡运动时间约为757 s,最大平均速度达到4.9 m/s,平均滑移距离约960 m。滑坡动力学过程可分为失稳滑动(0~18 s)、流态传播(18~331 s)及低速堆积(331~757 s)三个阶段,且在滑动过程中表现出了碎屑流滑坡的“超距、失距”特征以及碎屑流滑坡的体积增大效应。滑体在清江的堆积特征呈现靠近滑出崖口方向堆积较厚,远离滑坡方向较薄的类锥形堆积形态,模拟与实际情况吻合较好。模型较好的再现了沙子坝滑坡从失稳到堆积的滑动过程,通过该方法对滑坡变形及运动特征研究分析,可为类似碎屑流滑坡地质灾害的防治与研究提供的参考。

       

      Abstract: Debris flow landslides usually exhibit high sliding speed and long-distance slip, and their unstable slide is easy to cause serious damage to the surrounding area and significant property loss. On July 21, 2020, under the continuous influence of heavy rainfall, the Shaziba landslide in Enshi lost stability and transformed into a debris flow landslide, ultimately depositing within the Qing River, forming a dammed lake. To explore its kinematic features, such as velocity and displacement, during the Shaziba landslide's sliding process and the evolving patterns of the landslide mass, a three-dimensional numerical model of the landslide was constructed using high-precision ortho-images obtained from unmanned aerial vehicles (drones). The parameters of the model were calibrated based on the mechanical properties of the landslide mass obtained from laboratory tests. Finally, the Particle Flow Code (PFC3D) software was used to simulate the process of the Shaziba debris flow landslide from sliding to deposition. It is determined that the movement time of the landslide was approximately 757 seconds, with a maximum average velocity of 4.9 m/s, and an average sliding distance of about 960 m. The dynamic process of the landslide can be divided into three stages: unstable sliding (0~18 s), flow propagation (18~331 s), and low-speed deposition (331~757 s). Throughout the sliding process, it exhibited the characteristics of hyper-distance and loss-distance, as well as the volume-increasing effect of debris flow landslides. The deposition pattern of the landslide mass in the Qing River displayed a conical accumulation shape, with thick accumulation near the landslide exit and thin accumulation in the opposite direction of the landslide, which closely matched the actual situation. The model effectively reproduces the sliding process of the Shaziba landslide from instability to deposition. This study can provide valuable insights for the prevention and study of geological hazards related to debris flow landslides.

       

    /

    返回文章
    返回