桥梁施工对其下明挖地铁隧道结构安全性影响分析及对策

Analysis of the influence of bridge construction on the structural safety of the underlying open-excavated subway tunnel

讨论在隧道结构周围近距离施工桩基及桥台的情况,以沙湖环湖路南段工程以桥梁形式上跨武汉市轨道交通2号线中山北路停车场与武九铁路联络线工程为例,采用Midas GTS NX有限元分析计算软件,对明挖地铁隧道结构在上跨桥梁及其桩基施工过程中的内力、变形等进行了模拟分析。分析表明,隧道上方桥梁施工会使隧道结构竖向发生沉降、横向发生收敛、结构整体发生扭曲,但本工程桥梁施工对隧道结构的影响在安全范围内。

This paper took a bridge and an open-excavated subway tunnel in Wuhan as an example which the bridge was designed to be constructed above the tunnel.Considering the features that the distance between piles of the bridge and tunnel was very close and tunnels are located under the spot,this paper constructed a goodsized three-dimensional finite element model.The piles’influence on the underlying tunnel during the construction of the bridge was analysed using Midas GTS NX software.The simulation result showed that:the construction of bridge over the existing tunnel can lead to vertical subsidence,horizontal convergence pointing to the inside space and overall distortion of the tunnel structure,while the influence of bridge construction on tunnel structure is within the safe range.