薄壁箱梁剪力滞效应分析的组合单元法  

Combined Element Method for Shear Lag Effect Analysis of Thin-walled Box Girder

作　　者：骆佐龙 宋一凡[1] 贺拴海[1] 董峰辉[2] 

机构地区：[1]长安大学公路学院,陕西西安710064 [2]同济大学土木工程学院,上海200092

出　　处：《公路交通科技》2014年第9期58-63,75,共7页Journal of Highway and Transportation Research and Development

基　　金：交通运输部西部交通建设科技项目(2011 812 318 970);中央高校基本科研业务专项资金项目(CHD2012JC001)

摘　　要：针对薄壁箱梁剪力滞效应有限元计算单元自由度多,计算工作量大的的问题,提出一种考虑剪力滞效应的组合单元法。顶板采用平面板单元模拟,轴向位移插值函数取3次多项式;腹板及底板采用梁单元分析。为减少有限元分析的单元自由度数目,取顶板单元的节点位移参数为基本位移参数,腹板与底板的位移模式由顶板与腹板及腹板与底板的变形协调关系得到,最后通过变分原理得到组合单元的刚度矩阵。以一座实桥为工程背景,通过与有限元程序计算结果对比,得出此方法的计算精度较高,计算效率亦比较高。To cope with the problem of large number of free degree of finite element calculation for shear lag effect in thin-walled box girder and much computing workload,a combined element method considering shear lag effect is put forward. A plane element is adopted for simulating roof plate,a cubic polynomial is adopted as the interpolation function of axial displacement,and a beam element is adopted for analyzing web plates and bottom plate. In order to reduce the free degree number of element in finite analysis, the node displacement of roof plate element is taken as the basic displacement parameter,and the displacement modes of web plates and bottom plate are obtained by the deformation coordination relations of roof plate with web plates and web plates with bottom plate. Finally,the stiffness matrix of the composition element is got by variation principle. Taking a real bridge as an engineering background,by comparing with finite element calculation result,it is concluded that the accuracy and efficiency of the presented method are both higher.

关 键 词：桥梁工程 剪力滞效应 组合单元 薄壁箱梁 有限元 

分 类 号：U448.213[建筑科学—桥梁与隧道工程]