Abstract: Underwater inspection of a certain hydropower station revealed that the concrete of the second phase of the spillway gate slot, the concrete of the stilling pool, the foundation of the retaining tank and the downstream guide wall had suffered erosion damage. The reasons for the erosion of flood discharge and energy dissipation structures were analyzed from the perspectives of inflow conditions over the years, the hydraulic design of flood discharge and energy dissipation facilities, the construction quality of the stilling pool, and the opening and closing procedures of the gates. On this basis, engineering measures such as optimizing the shape of the energy dissipation pool and promptly repairing the damaged parts were proposed. In addition, management measures such as conducting flow state observation and recording during flood discharge, refining the gate opening and closing procedures, regularly carrying out underwater inspections, and promptly eliminating defects were proposed.

Key words: underwater inspection, flood discharge and energy dissipation structures, scour, causes analysis, treatment suggestions

摘要： 某水电站水下检查发现泄洪闸门槽二期混凝土、消力池混凝土、护坦基础及下游导墙等部位出现冲刷破坏。从历年来水情况、泄洪消能设施的水力学设计、消力池施工质量、闸门启闭程序等方面对泄洪消能建筑物冲刷原因进行分析，在此基础上，提出了优化消力池体型、及时修补损坏部位等工程措施。此外，还提出了观察记录泄洪流态、细化闸门启闭程序、定期开展水下检查和及时消缺的管理措施。

关键词: 水下检查, 泄洪消能建筑物, 淘刷, 原因分析, 处理建议