三峡水库区何家湾滑坡监测及防治措施研究

Monitoring and countermeasures of Hejiawan Landslide in the Three Gorges Reservoir area

在研究了三峡水库区何家湾滑坡体空间形态、自然地理及地层岩性的基础上,从气象、水文、库区蓄水及水位变动因素入手,分析了滑坡形成的原因。根据库区地质灾害监测预警工程设计,结合何家湾滑坡的结构和变形特征,确定具体监测方法。对该滑坡进行了大地形变监测、地下水位监测、滑体深部位移监测及宏观监测。其中,大地形变监测数据分析表明:何家湾滑坡的最大变形量已超过2cm,且一直呈现增大趋势;地下水位、滑体深部位移均未发现明显异常,宏观监测亦未发现明显的新的变形迹象。通过分析监测资料并考虑到未来三峡水库蓄水,认为何家湾滑坡目前处于潜在不稳定状态。滑坡体在饱水及水库蓄水后,将处于临界蠕滑或失稳状态。结合滑坡体实际情况对滑坡防治进行初步研究,提出了采用回填压脚支档为主、辅以排水的综合治理措施;并建议加强数据远程传输的研究与实践,以解决目前监测效率不高的问题。

Based on the slide mass structure, physical geography and stratum lithology of Hejiawan Landslide, studying on the two factors which influence the stability of Hejiawan Landslide, this paper analyses the causes of landslide formation. The monitoring plan was laid out based on the geological hazard prevention design. The monitoring to earth transmutation, ground water level, deep slide mass displacement and macroscopic state have been actualized for Hejiawan Landslide, and the data show that the value of distortion has exceeded 2era, while groundwater level and deep slide mass displacement do not have obvious change. According to the monitoring data and taking the impoundment of Three Gorges Reservoir into account, the Hejiawan Landslide is under unstabile state. The landslide will be in critical creeping motion or at the unsteady state after impoundment. Considering the practical situation and studying on control measurement for slope, the backfill toe weight and drainage system are adopted to keep the slide mass stable. For improving efficiency of monitoring, it is suggested to put more energy on the study and practice of data transfer.