拉索钢拱桥吊耳设计及局部受力分析

Design and Local Force Analysis on Lifting Lug of Cable Steel Arch Bridge

拉索钢拱桥的主受力结构是钢拱及钢梁,吊耳是连接钢拱和钢梁的重要传力构件。由于吊耳尺寸及构造受到安装工艺、操作空间、材料质量等限制,其受力较为复杂,吊耳局部应力分析一直是拉索钢拱桥设计计算的关键。本文以某特大跨拉索钢拱桥为工程实例,建立有限元数值模型对吊耳及其拱肋隔板的受力进行计算,分析吊耳在作用基本组合最大拉索力作用下的受力情况,建模时应用单位力荷载刚度法,考虑了拱肋其他部分对计算模型的刚度影响。相关经验可为以后相关类型的工程提供参考。

The main bearing structure of the steel arch bridge is steel arch and steel beam,and the lifting lug is an important force transfer member connecting the steel arch and steel beam.Due to the limitations of installation technology,operating space,and material quality on the size and structure of the lifting lug,its stress is relatively complex.Local stress analysis of the lifting lug has always been the key to the design and calculation of cable steel arch bridges.In this paper,a large span cable steel arch bridge was taken as an engineering example,the finite element numerical model was established to calculate the forces on the lifting lug and its arch rib partition,and the forces on the lifting lug under the maximum cable force of the basic combination were analyzed.The stiffness method of unit force load was applied in the modeling,and the influence of other parts of the arch rib on the stiffness of the calculation model was considered.Some relevant experience can provide reference for related types of projects in future.