钢架桥施工对下穿隧道的影响

The Impact of Steel Frame Bridge Construction on Underpass Tunnels

鉴于钢架桥的施工往往会对其下穿隧道产生一定的影响,文章运用有限元软件Midas GTS NX建立三维模型,研究钢架桥施工对下穿隧道的影响。研究结果发现:使用摩擦型桩基的钢架桥,在施工过程中引起的隧道变形以竖向沉降为主,且桩基距隧道的距离越近,隧道结构的变形越明显;钢架桥桩基及上部结构施工过程中,会引起衬砌水平向和竖向的收敛,且有衬砌的竖向的收敛值大于水平向的收敛值;钢架桥施工过程中,桩基轴力表现出由上至下逐渐减小的特点,侧摩阻力表现为由上至下逐渐增大的特点,这与实际工程中摩擦型桩的工作机理相一致。

In view of the construction of the steel frame bridge,it often has a certain impact on its underpass tunnel.This paper uses the finite element software Midas GTS NX to establish a three-dimensional model to study the impact of steel frame construction on the lower tunnel.The results of the study found that the steel frame with friction pile foundation was mainly based on the vertical settlement of the tunnel caused by the construction process,and the closer the distance of the pile base distance,the more obvious the deformation of the tunnel structure;the steel frame pile during the construction of the base and the upper structure,the level of lining and vertical convergence will cause the vertical convergence value of the lining.The characteristics of gradually decreased,resistance of the side motorcycles is the characteristics of gradually increasing,which is consistent with the working mechanism of the actual medium friction pile.