斜拉桥扁平钢箱梁空间有限元分析

Analysis on Flat Steel-Box-Girder of Cable-stayed Bridge by Spatial Finite-Element Method

斜拉桥扁平钢箱梁是空间复杂受力的结构体系,是设计的关键部位。本文以一座稀索体系钢箱梁斜拉桥为背景,建立扁平钢箱梁板壳有限元节段模型,对其进行空间应力分析。考虑到梁段以外附近区域的作用,在梁两端截面上施加由平面杆系结构分析所得的端面内力;另外,恒载及汽车荷载也施加在相应的位置,分析了扁平钢箱梁在最不利荷载组合作用下的空间应力效应;并在考虑几何非线性和材料非线性的基础上,对扁平钢箱梁进行极限承载力分析。为扁平钢箱梁的设计提供参考。

Flat steel-box-girder of cable-stayed bridge is a complicated load bearing structural system and the key part in design. The fiat steel-box-girder patter of a partially cable-stayed bridge subjected was presented; the finite-element model with shell element was established. Three dimensional stress distribution characteristics of the model were analyzed. In order to consider the affections of the adjacent zone out of the girder section, the internal-forces of two-end surface that were obtained by the horizontal shaft analysis were exerted on model. Moreover, the weight and vehicle loading were considered. Based on above, a spatial analysis about elastic behavior of steel girder is discussed. At the same time, taking geometric non-linearity and material non-linearity into account to study ultimate bearing capacity of steel girder. During these courses some useful conclusion is obtained, and it is beneficial to the design of Flat steel-box-girder.