一、前言天生桥二级水电站位于黔、桂交界红水河上游南盘江上,系采用低坝长隧洞地面厂房的形式引水发电,总装机容量132万kW。工程地区山高谷深,地质情况复杂;由于建筑物布置的需要,引起了几处滑坡。位于厂房西坡坡顶的滑坡——下山包滑坡为本工程遇到的较大滑坡,坡体体积达140万m~3,直接对厂房的施工和运行造成威协。对于该滑坡的治理我们采用了多种措施,其中1200kN预应力自由锚索是 I. Introduction The Tianshengqiao II Hydropower Station is located on the Nanpanjiang River upstream of Hongshui River in Guizhou and Guangxi. It uses diversion power generation in the form of ground floor of low-rise long tunnel and has a total installed capacity of 1.32 million kW. The mountainous areas and deep valleys in the project area have complex geological conditions; due to the need of building layout, several landslides are caused. The landslide - Xia Shan Bao landslide located at the top of the west slope of the plant is a large landslide encountered in this project. The volume of the slope body reaches 1.4 million m 3, which directly causes the threat to the construction and operation of the plant. We used a variety of measures for the management of the landslide, of which 1200 kN prestressed free anchor is