Abstract: In order to study the valley deformation and slope stability of the dam area of Wudongde hydropower station on Jinsha River, the high slope of the plunge pond behind the dam is taken as an example. Based on the monitoring results of the slope, the stability of slope and the development law of valley deformation are analyzed. The stability of high slopes at both sides of the dam area is calculated by using the finite element method with selected typical sections. The simulation results have good consistency with the slope monitoring results during excavation. The monitoring results reveal the general law of valley deformation, show that excavation disturbances will accelerate the rheological deformation of the rock mass in the dam area. It is reasonable and feasible to analyze and evaluate the slope stability of dam area by deformation monitoring combined with simulation. This intuitive and adaptable method can take into account of the large non-linear deformation of rock mass, quickly obtain the safety factor of slope, and conveniently simulate the process of instability and failure of any landform and sliding surface.

Key words: valley deformation, rock mass, stability

摘要： 为了研究水电站坝区谷幅变形和边坡稳定性，以金沙江乌东德水电站坝后水垫塘高边坡为例，基于坝后水垫塘边坡监测成果，分析了边坡的稳定性及谷幅变形发展规律。通过选取不同的典型剖面，采用有限元法计算了坝区两岸高边坡稳定性。仿真模拟结果与开挖期间边坡监测成果具有良好的一致性。监测成果揭示了谷幅变形的一般性规律，表明开挖扰动等将加快坝区岩体的流变变形。实践表明，通过变形监测结合仿真模拟，对水电站坝区边坡稳定性进行分析评价合理可行。该方法可考虑岩土体的非线性大变形，迅速求得边坡安全系数，且方便模拟任何地貌、任意形状滑动面的失稳破坏过程，直观性与适用性强。

关键词: 谷幅变形, 岩体, 稳定性