拉哇水电站高陡峭岸坡开挖支护施工技术

Excavation and Support Construction Technology for High and Steep Bank Slopes of Lawa Hydropower Station

在大型水电工程建设中,高陡峭岸坡的开挖支护施工具有体型复杂、范围广、坡道陡峭、施工条件差等特点,已成为影响工程施工安全、进度、质量、效益的严峻挑战。如何克服在强卸荷带区域、倒悬体区域、危岩体区域、有较大节理裂隙发育区域等多类型不良地质条件的施工难点,使预裂爆破控制技术增强预留面边坡的稳定性、降低开挖施工难度、加快施工进度,已成为复杂地质条件下提高施工质量的当务之急。本文通过对拉哇水电站上游围堰高陡峭岸坡开挖施工技术进行总结,以供类似工程参考和借鉴。

In the construction of large-scale hydropower projects,the excavation and support construction for high and steep bank slopes has the characteristics of complex shape,wide scope,steep slopes and poor construction conditions,which has become a serious challenge to the safety,progress,quality and benefit of the construction.How to overcome the construction difficulties in the areas with unfavorable geological conditions such as strong unloading zone,overhanging body,dangerous rock mass and the area with large joints and fissures,etc.,adopt the pre-splitting blasting control technology to enhance the stability of slope,reduce the difficulty of excavation and speed up the construction progress have become the top priority for improving the construction quality under complex geological conditions.In this paper,the construction technology of high and steep bank slope excavation of upstream cofferdam of Lawa Hydropower Station is summarized,which can provide reference for similar projects.