地铁隧道近距离穿越既有老旧隧道方案设计

Design of a Subway Tunnel Crossing the Existing Old Tunnel at a Close Distance

随着城市轨道交通建设的迅猛发展,新建地铁隧道近距离穿越既有老旧铁路隧道的工程越来越多。结合既有老旧京广铁路隧道所处的复杂地质环境及其结构受损、漏水严重等现状,分析了长沙地铁7号线铁道学院东站~雨花亭站区间穿越该老旧隧道的线路方案比选过程,并通过数值模拟等手段对西线上穿盾构、暗挖及明挖等设计方案进行了深入比较。在综合考虑与其他工程的冲突及线路坡度问题后,选择了西线上穿方案;基于对下部既有老旧隧道扰动最小,并有利于对既有老旧隧道长期保护的考虑,选择了明挖施工。该工程方案设计可为类似工程设计与施工提供参考。

With the rapid development of the urban rail transit construction,the number of new subway tunnels crossing through existing old railway tunnels at short distance is increasing.Based on the complex geological environment of the existing old Beijing Guangzhou railway tunnel and the current condition of the structural damage and the serious water leakage,the alignment selection options of crossing the old tunnel by the east station of the Railway College and Yuhuating station of the Changsha Metro Line 7 is analyzed,the design options of the shielded,underground excavation and open excavation on the west line by means of numerical simulation are compared.After comprehensively considering the conflict with other projects and the slope of the line,the upper crossing options of the west line is selected.Based on the consideration that the disturbance to the existing old tunnel in the lower part is minimal and is conducive to the long-term protection of the existing old tunnel,the open excavation construction is selected and finally the open excavation is selected.This experience provides a reference for the design and construction of similar projects.