盾构隧道侧穿引起桥梁桩基础变形的数值研究

Numerical Study on Deformation of Bridge Pile Foundation Caused by Shield Tunnel Side Crossing

以某城市轨道交通隧道侧穿桥梁基础工程为研究对象,借助FLAC3D数值模拟软件,深入分析隧道埋深、桩基础与隧道水平轴线和破裂面的相对位置、隧道穿过桩基础偏心比等3个重要因素对桩基础变形的影响。由数值分析计算结果可知,隧道侧穿桩基础时,桩基础竖向变形具有线性分布特征,随着偏心比不断增加,桩基础竖向变形先增大后减小;桩基础中心轴线与隧道轴线两者之间距离越远,桩基础整体竖向沉降变形越小;当偏心比随隧道埋深增加时桩基础变形增大。研究结果可以为隧道施工提供理论分析支撑,做好相关预防措施,提高施工安全性。

Taking an urban rail transit tunnel side-crossing bridge foundation engineering as the research object,with the help of FLAC3D numerical simulation software,the influence of three important factors on the deformation of pile foundation is analyzed,such as the buried depth of tunnel,the relative position of pile foundation and the horizontal axis and fracture surface of tunnel,and the eccentricity ratio of tunnel passing through pile foundation.From the numerical analysis and calculation results,it can be seen that when the tunnel laterally penetrates the pile foundation,the vertical deformation of the pile foundation has linear distribution characteristics.As the eccentricity ratio increases,the vertical deformation of the pile foundation first increases and then decreases;the farther the distance between the central axis of pile foundation and tunnel axis is,the smaller the overall vertical settlement deformation of pile foundation is;when the eccentricity ratio increases with the depth of the tunnel,the deformation of the pile foundation increases.The research results can provide theoretical analysis support for tunnel construction,take relevant preventive measures,and improve construction safety.