Abstract: Guide wall between power house and dam of Shaping Ⅱ hydropower station is used as the fishway during operation and as the longitudinal water retaining cofferdam of powerhouse foundation pit during the second construction stage. During water retaining, the elevation difference between the powerhouse foundation pit and the top of guide wall is up to 50 m, and there are shale interlayer Sh4 with gentle dip angle and crack L22 at the bottom of guide wall, which can lead to sliding problems. Therefore, the stability of guide wall is particularly important. Based on the calculation results of anti-sliding stability, the guide wall foundation is reinforced by anchor pile and consolidated grouting. The operation shows that the design is successful and can provide useful reference for other similar projects.

Key words: Shaping Ⅱ hydropower station, guide wall between power house and dam, longitudinal cofferdam, deep anti-sliding stability

摘要： 大渡河沙坪二级水电站厂坝间导墙在运行期兼作鱼道，在二期施工导流中兼作厂房基坑纵向挡水围堰，起到了“一墙三用”效果。施工挡水期间，厂房基坑底与导墙顶高差达50 m，且在导墙底部存在缓倾角页岩夹层Sh4及裂隙L22，存在深层抗滑稳定问题，因此其稳定性显得尤为重要。本工程根据导墙建基面抗滑稳定及应力、深层抗滑稳定计算成果对导墙基础采取了锚筋桩及固结灌浆等加固处理，从运行情况看，该设计是成功的，可为其他类似工程提供有益的借鉴和参考。

关键词: 沙坪二级水电站, 厂坝间导墙, 纵向围堰, 深层抗滑稳定