多时相数字孪生滑坡变形监测方法与应用研究--以金沙江白格滑坡为例

Multi-temporal digital twin method and application of landslide deformation monitoring:A case study on Baige landslide in Jinsha River

高位隐蔽滑坡因为难到达、难识别、难监测,致使成灾表现具有极强的突发性和破坏性。针对传统人工地面调查和地面布设监测设备存在危险系数高、工作效率低、设备易损坏和离线误报率高等问题,提出基于无人机倾斜摄影测量技术构建高位隐蔽滑坡数字孪生体的方法,通过信息化、数字化手段对地质灾害变形特征及时空演化规律进行监测分析。以西藏金沙江白格滑坡为研究对象,利用无人机倾斜摄影测量技术获取2019年4月—2021年9月共计10期次航测数据,融合多源数据构建了多时相数字孪生滑坡体,通过多期孪生滑坡体实现对白格滑坡整体滑移、局部微变形、滑塌体积等多维要素的高精度定量分析,并及时应用于白格滑坡时空演化分析和监测预警中。研究表明:白格滑坡在2019—2021年监测期内存在持续变形迹象,强变形主要位于滑坡两侧及后缘,渐有扩大趋势,存在垮塌堵江风险。运用多时相数字孪生滑坡变形监测手段实现对地质灾害定性-定量化特征描述与风险评估,具有快速灵活、覆盖全面、不受复杂艰险地形条件限制等优势,可为高位隐蔽滑坡等斜坡灾害大梯度形变监测提供工程实践参考。

High-locality and hidden landslides,due to its significant characteristics of being difficult to access,identify,and monitor,have strong suddenness and destructiveness when they occur.Continuous monitoring and risk assessment of these landslides are of great significance.Traditional artificial ground survey methods and ground monitoring equipment have the characteristics of high risk,low efficiency,easy damage to equipment,and frequent offline false alarms.Thus,based on unmanned aerial vehicle(UAV)tilt photogrammetry,this study attempts to provide a digital twin method to characterize high-locality and hidden landslides by monitoring and analyzing the deformation and spatiotemporal evolution of geological disasters.This study uses UAV tilt photogrammetry technology to obtain 10 periods of aerial survey data of the Baige landslide on the Jinsha River in Tibet as the research area from April 2019 to September 2021.A multi-temporal digital twin landslide body is constructed,and high-precision quantitative monitoring of multi-dimensional factors,such as the overall sliding characteristics,local micro deformation,and collapse volume of the Baige landslide,is achieved,which are applied to the monitoring and warning of Baige landslide.The results show that there are signs of continuous deformation in the Baige landslide during the monitoring period from 2019 to 2021,and strong deformation mainly occurs at both sides and rear edges of the landslide,gradually expanding,and posing a risk of collapse and river blockage.The multi-temporal digital twin method and application of landslide deformation monitoring on qualitative and quantitative characteristics description and risk assessment of geological disasters are further analyzed.The method in this study has the advantages of fast and flexible,comprehensive coverage,and not limited by complex and dangerous terrain conditions,which could provide information for the large gradient deformation monitoring and engineering practice of slope disasters,such as high-locality and hidden landslides.