地铁隧道下穿城市既有桥梁的数值模拟分析

Numerical Simulation Analysis of Metro Tunnel under Crossing Existing Urban Bridge

为分析地铁隧道下穿既有桥梁的影响,以广州地铁某盾构隧道下穿既有桥梁为工程背景,建立三维有限元模型,分析了盾构隧道掘进施工对土体位移、隧道变形及桥梁变形的影响。通过数值模拟分析得出:土体位移、隧道变形及桥梁变形均满足变形控制标准要求,因此盾构隧道掘进施工不会危害桥梁结构的正常运营,既有桥梁在隧道掘进施工过程中是安全的。

In order to analyze the impact of a metro tunnel crossing an existing bridge,a threedimensional finite element model was established based on the engineering background of a shield tunnel crossing an existing bridge in Guangzhou Metro.The influence of shield tunneling on soil displacement,tunnel deformation and bridge deformation was analyzed.Through numerical simulation analysis,it is concluded that the soil displacement,tunnel deformation and bridge deformation all meet the requirements of deformation control standards,so the shield tunneling construction will not endanger the normal operation of the bridge structure,and the existing bridge is safe during the tunneling construction.