Abstract: Pubugou dam is a gravel-soil-core rock-fill dam, if the upstream slope fails, the surge wave would pose great danger to the dam and block the intakes. Given those factors, the deformation and fracture mass is designed as a B1 slope. The slope is divided into 3 zones surface loose zone with small scale slip from the surface to inner layer, off-load deformation zone with relaxed-tension crack and sound rock zone. After detailed exploration, we analysed the slope structure, failure pattern and stability zoning according to the geological conditions. In line with the deformation and failure features and the construction progress of pubugou hydropower station, we took reinforcement measures which contain no excavation, strong support (deep anchorage and surface support), support at different periods and areas, and integral control. Those measures are dynamically adjusted and designed with real time monitoring results. Analysis on the monitoring result after the first stage and preliminary treatment of second stage shows that the deformation trend is becoming slower and no abnormal deformation or sliding layer occurs. In order to provide basis for optimization and make sure the slope is stable in the future, the analysis on the monitoring result is highlighted. This paper provides design idea, reinforcement measures, calculation method, monitoring apporoaches and evaluation process for other similar conditions.

Key words: deforming and cracking slope, stability analysis, by areas and stages, dynamic design, slope monitoring, Pubugou power station