巴贡水电站引水隧洞竖井开挖施工

Excavation of Shaft in Headrace Tunnel at Bakun Hydropower Station

巴贡水电站8条引水隧洞竖井开挖施工包括一部分上、下弯段和竖直段开挖,采用反井钻机先钻φ1.4 m导井,再自下而上扩挖为φ3.6 m导井,最后自上而下全断面扩挖完成的施工方法。8条竖井均安全、顺利地完成,并在质量、效益方面都取得了良好的成绩。简述了巴贡水电站引水隧洞竖井的反井钻机施工位置选址和上弯段开挖方案、反井钻机施工导井、导井扩挖、竖井全断面扩挖。

Excavation of shafts in 8 headrace tunnels at Bakun hydropower station includes excavation of part of upper bend sections,lower bend sections and vertical shaft sections.Pilot tunnel with diameter Ф1.4m is drilled by raise-boring machine,the pilot tunnel is enlarged from bottom to top and then full section excavation is carried out from top to bottom.8 shafts are constructed safely and successfully and gain good achievements in quality and benefits.This paper gives brief description of construction location selection of raise-boring machine,upper bend section excavation scheme,pilot tunnel constructed by raise-boring machine,pilot tunnel enlargement and shaft full section excavation for Bakun headrace tunnel.