Abstract: During operation, the defects of hydraulic structures would gradually occur in complex water environment, especially the second stage concrete of the gate slot. The defects repair and treatment would affect the operation income of the station, as well as the safety of the station itself and downstream structures. There are few successful underwater repair cases without water discharge during operation at home and abroad. The repair of the second stage concrete of trash rack gate slot of Xiushan hydropower station in Hunan province is introduced as an example. The counter-force frame of trash rack gate is used as the template support system, fine stone self-compacting non-diffusible concrete is poured based on the groove depth, and underwater epoxy mortar plastering method is adopted to repair the second stage concrete of trash rack gate slot. The repair technology is also successfully applied to second stage entrance gate slot of Anjiang hydropower station in Hunan province, which can provide reference for other similar projects.

Key words: second stage gate slot, repair technology, operation period

摘要： 运营期间，水工建筑物缺陷在复杂水环境下逐渐暴露，尤其是门槽二期混凝土，其缺陷修复处理影响了电站运营收益和电站及下游建筑物的安全，国内外对运营期非泄水水下修复施工的成功案例较少。以湖南修山水电站拦污栅门槽二期混凝土为例，通过拦污栅闸门反力架，形成模板支撑体系，根据不同槽深灌注细石自密实水下不扩散混凝土和采用水下环氧砂浆批荡方法，对发电期水下门槽二期混凝土进行了修复。该技术还成功推广应用于湖南安江水电站进口门槽二期，可为其他类似项目提供借鉴。

关键词: 二期门槽, 修复技术, 运营期