隧道穿越活动断层抗位错量研究

Research on Anti-dislocation Amount of Tunnel Crossing Active Fault

目前,国内外的隧洞相关规范均就隧洞穿越活动断层带的工程设计提出了针对活动断层等不良地质应以避让为主的原则,但具体的应对措施并未做出明确规定和建议。本文通过介绍国内外隧洞穿越活动断层的3个典型工程案例,总结了已建工程中常采用的柔性连接段、复合式衬砌结构、综合方法等应对措施,得出以下两方面结论:一是隧道穿越活断层段结构抗震设计应以衬砌结构局部损伤经加固后可继续使用做为设计目标;二是以设计使用年限内的总滑动量做为确定隧道最小净空的控制因素。同时让上述结论应用于阿尔金山隧道穿越F7活动断层段隧道设计,具体方法为隧道净空径向扩大40 cm。

At present,domestic and foreign tunnel related codes have all put forward the principle of avoiding active faults and other bad geology for the engineering design of tunnels crossing active fault zones,but the specific countermeasures have not made clear regulations and suggestions.This paper introduced three typical engineering cases of tunnels crossing active faults at home and abroad,and summarized the flexible connecting sections,composite lining structures,comprehensive methods and other countermeasures commonly used in existing projects,and drawed the following two conclusions.The first is that the anti-seismic design of tunnel crossing active fault section structure should take the local damage of the lining structure after reinforcement as the design goal.The second is that the total sliding volume within the design service life is taken as the controlling factor to determine the minimum clearance of the tunnel.At the same time,the above conclusion was applied to the tunnel design of the Altun Mountain Tunnel crossing the F7 active fault.The specific method is to expand the tunnel clearance by 40 cm radially.