双孔平行地铁顺穿桥梁对桥梁桩基础影响研究

Study on Influence of Double-hole Parallel Subway Running through Bridge on Pile Foundation of Bridge

摘要:

利用有限元分析软件建立桥梁基础及双孔地铁的模型，模拟地铁盾构的施工工况。研究盾构施工前后地铁隧道、周边土体变形趋势及其对地铁顺穿桥梁的桩基础轴力、弯矩、水平变形及沉降的影响。分析结果表明：隧道施工造成隧道上部土体沉降，下部土体隆起，隧道呈现椭圆形；其顺穿桥梁桩基轴力、弯矩增加幅度较大，桩基在地铁隧道深度以上竖向沉降，在隧道深度下局部桩体隆起，桩身位移呈现“3”字形，最大位移位于隧道中心标高与隧道底标高之间。

Abstract:

The model of bridge foundation and double-hole subway is established by using the finite element analysis software to simulate the shield construction condition of subway. The deformation trend of subway tunnel and surrounding soil before and after shield construction, and its influence on the axial force, bending moment, horizontal deformation and settlement of pile foundation of subway running through bridge are studied. The analysis results show that the tunnel construction causes the soil settlement in the upper part of the tunnel, the soil uplift in the lower part of the tunnel, and the tunnel presenting an oval shape. The axial force and bending moment of the pile foundation through the bridge increase greatly. The pile foundation presents the vertical settlement above the depth of subway tunnel. The local piles uplift at the tunnel depth. The pile displacement presents a "3" shape. The maximum displacement lies between the central elevation and the bottom elevation of the tunnel.