大跨度坦拱桥拱肋分叉处的三维仿真分析

Three-dimensional Simulation Analysis of Arch Rib Crotch in a Large-span Flat Arch Bridge

宁波市澄浪桥主桥是一大跨度坦拱桥,其主拱拱肋在主跨跨径1/4处由1个封闭钢箱分叉为2个封闭钢箱。分叉处拱肋节点构造复杂,需要精细的三维有限元仿真分析验证构造设计的有效性。利用结构分析软件ANSYS建立主拱分叉处节段的三维有限元仿真分析模型,分析模型利用与Midas梁单元分析结果的比较得到验证。利用仿真分析模型,计算得到拱肋分叉处节段的应力分布,并分析其局部屈曲效应。仿真分析结果为验证与优化拱肋分叉处构造设计提供理论依据。

The main bridge of Ningbo Chenglang Bridge is a large- span flat arch bridge,and its main arch rib is bifurcated from one closed steel box into two at 1/4 main spaa The joint structure at the location of arch rib crotch is complicated,which needs 3D finite element simulation analysis to validate the effectiveness of structure design.By use of the structural analysis software ANSYS,this paper establishes three- dimensional finite element simulation analysis model of segment at arch crotch,which is verified by comparison of analysis results with Midas beam element model.Using the model to calculate this paper obtains stress distribution of the segment at arch rib crotch,and analyzes its effects of local buckling The simulation results provide a theoretical basis for verification and optimization of structure design of arch rib crotch.