古城水电站引水隧洞开挖与支护施工

Diversion Tunnel Excavation and Support Construction in Gucheng Hydropower Station

针对古城水电站引水隧洞开挖具有线路长,开挖断面大和地质条件差的特点,在施工中采用了分层钻爆法开挖和锚喷、挂网、架立钢支撑等初期临时柔性支护措施,待围岩变形基本稳定以后,再采用钢筋混凝土衬砌永久支护,满足设计和业主的要求,在工程进度和质量安全方面取得较好的效果。

Construction of the diversion tunnel in Gucheng Hydropower Station is of considerable difficulties because of its long tunnel length, big excavation section and poor geological condition. Thus, in the early stage of the excavation, the layered drilling and blasting excavation technique and temporary soft supporting measures such as the anchoring and shotcreting, meshing and steel support installation are adopted. After the deformation of the surrounding rock is basically stable, permanent reinforced concrete lining is then applied. Practice shows that the construction is satisfying in the project schedule, quality and safety.