复杂地质条件下大型导流洞群快速开挖施工技术

Rapid Excavation Construction Technology for Large-sized Diversion Tunnel Group under Difficult Geological Conditions

白鹤滩水电站左岸导流洞具有开挖断面大、地质条件复杂、开挖支护施工强度高、施工工期极其紧张等施工特点和难点。介绍了在层间、层内错动带、高地应力引起岩爆、玄武岩柱状节理等不良地质条件下,通过采用科学的开挖支护方案和程序,该大型导流洞群洞挖创造了40.65万m3/月的月开挖强度记录,可为同类工程提供借鉴。

The diversion tunnel in left bank of Baihetan hydropower station is characterized with large excavation section,difficult geological conditions,large excavation volume and large quantities of supports,intensive construction period.In this paper,a scientific method for excavation and support in tunnels under poor geological conditions,such as interlayer shear zones,the fault zones,rock burst caused by high in-situ stress and basalt columnar joints,is presented.A record of monthly excavation volume of 40.65m3m3 / is created for large-sized diversion tunnel group excavation and this provides references to the similar projects.