小湾水电站工程特高边坡开挖安全稳定技术研究

Technical Study on Safe and Stable Excavation of Extrahigh Side Slope for Xiaowan Hydropower Station Project

小湾水电站工程边坡开挖高度近700 m,为世界罕见的特高边坡,同时存在地质条件复杂、岸坡陡直、开挖与支护强度大、立体交叉作业等特点,采取了合理布置设备、加强安全防护、严格施工程序等措施,合理协调开挖与支护的对立统一关系,按照"排水优先、重视锁口、系统支护、及时监测"的程序,保证高边坡的稳定,并在堆积体首次尝试大规模预应力锚索加固取得成功。

The side slope at Xiaowan Hydropower Station has an excavation height of about 700m, and is ranked as an extra-high side slope seldom found in the world. Given such engineering conditions as complex geological conditions, steep bank slope, strong intensity of excavation and support engineering, as well as three dimension- al and cross operation, a series of measures are taken to coordinate the relation between excavation and support engineering with an aim to maintain stability of such high side slope, such as rational layout of equipment, intensified safe precautions and well-defined engineering procedures as ＂drainage first, highlighted locking notch, systematic support engineering and timely supervision＂. The first attempt to reinforce with pre-stressed anchor cable on a large scale yields successful results.