隧道施工对既有桥梁墩台与基础受力与变形影响数值模拟分析

Numerical Simulation Analysis of Effects of Tunnel Construction on Stress and Deformation of Existing Bridge Piers,Abutments,and Foundations

依托玉磨铁路隧道近距离穿越思小高速公路桥梁桩基工程,建立有限元模型,研究隧道施工对既有桥梁墩台与基础受力与变形影响。分析结果表明:隧道开挖对高速公路桥梁桩基的最不利影响范围为以距桩基最近的开挖段面为中心,前后两个开挖段;隧道在高速公路最不利范围内施工时,桩身上部沉降和水平位移较大,桩身下部沉降和水平位移较小;思小高速4号桥墩与基础的变形值满足其稳定性的要求;隧道施工对桩身轴力及摩阻力的影响极小。

Based on the bridge pier foundation engineering of Yumo Railway Tunnel closely crossing Sixiao Expressway,a finite element model was established to study the effects of the tunnel construction on the stress and deformation of the existing bridge piers,abutments,and foundations.The analysis results showed that the most unfavorable influencing range of the tunnel excavation on the expressway bridge pier foundation was the front and back excavation sections centered on the closest excavation surface.When the tunnel construction was in the most unfavorable range of the expressway,the settlement and horizontal displacement of the upper pile were large and those of the lower pile were small.The deformation of Pier No.4 and the foundation of Sixiao Expressway met the stability requirements.The tunnel construction had little effect on the axial force and frictional resistance of the pile.