人行天桥施工和运营对既有隧道的影响研究

Research on the Impact of Pedestrian Bridge Construction and Operation on Existing Tunnels

以合肥市某道路改造中新建人行天桥项目为工程背景,采用Midas/GTSNX有限元分析软件构建三维数值分析模型,对近距离钻孔灌注桩施工、人行天桥上部结构施工和人行天桥运营阶段对既有隧道的影响进行了分析。分析结果表明,基坑开挖与桩基施工、上部结构施工两阶段对隧道结构和土体的位移影响明显;在运营阶段,隧道结构和土体的位移几乎没有变化。基坑开挖与桩基施工、上部结构施工两个阶段对隧道的弯矩影响明显;在运营阶段,隧道的弯矩变化很小。隧道结构和土体在人行天桥各施工阶段的水平和竖向位移均在安全控制值的范围内,满足地铁安全运营的要求。

Takes a new pedestrian bridge project in the reconstruction of a road in Hefei City as the engineering background,uses Midas/GTS NX finite element analysis software to build a three-dimensional numerical analysis model.The short-distance bored pile construction,the pedestrian bridge superstructure construction and the pedestrian bridge operation stage analyze the impact of existing tunnels.The analysis results show that the two stage of foundation pit excavation and pile foundation construction,superstructure construction have obvious effects on the displacement of the tunnel structure and soil;during the operation phase,the displacement of the tunnel structure and the soil hardly changes.The bending moment of the tunnel is obviously influenced by the the two stage of foundation pit excavation and pile foundation construction,superstructure construction;during the operation phase,the bending moment of the tunnel changes little.The horizontal and vertical displacements of the tunnel in each construction phase of the pedestrian bridge are within the range of the safety control value,which meets the requirements of the safe operation of the subway.