新建大断面盾构隧道下穿既有地铁隧道安全性分析  

Safety Analysis of the Newly-built Large Section Shield Tunnel Underpassing the Existing Metro Tunnel

作　　者：冯志华 Feng Zhihua(Hebei Provincial Communications Planning,Design and Research Institute Co.,Ltd.,Shijiazhuang 050011,China)

机构地区：[1]河北省交通规划设计研究院有限公司,石家庄市050011

出　　处：《北方交通》2025年第4期83-86,90,共5页Northern Communications

摘　　要：为研究某大断面盾构下穿对既有地铁隧道的影响,采用数值模拟精确建模,分析了不考虑上方既有地铁动荷载的开挖阶段与开挖后考虑地铁动荷载两种工况问题。结果表明:下部隧道施工阶段,在不考虑列车荷载情况下,既有隧道拱顶沉降量最大值为1.85mm,新建隧道拱顶沉降量最大值为4.37mm。新建盾构隧道南线开挖对土地的扰动比北侧更大。运营阶段,当列车在上部既有隧道对向运行时,交叉断面是最不利断面。数值分析揭示了新建隧道对既有隧道影响大小、分布规律,以及施工控制与监测工作的重点。In order to study the influence of a large section shield tunnel underpassing the existing metro tunnel,the numerical simulation and accurate modeling are used to analyze two kinds of operating conditions,i.e.not considering the excavation phase of the dynamic load of the existing metro in the upper part and considering the dynamic load of the metro after excavation.The results show that:in the construction stage of the lower tunnel,without considering the train load,the maximum settlement of the arch crown of the existing tunnel is 1.85mm,and that of the newly-built tunnel is 4.37mm.The excavation of the south line of the new shield tunnel has greater disturbance to the land than that of the north side.During the operation phase,when the train has opposing movement in the existing tunnel in the upper part,the crossing section is the most unfavorable section.The numerical analysis shows the magnitude and regular distribution of the influence of the newly-built tunnel on the existing tunnel,as well as the key working points of construction control and monitoring.

关 键 词：盾构隧道 列车荷载 微扰动 作用机理 监控量测 

分 类 号：U455.43[建筑科学—桥梁与隧道工程]