城市轨道钢箱梁天桥结构二阶弹塑性稳定分析——基于人行天桥  

Second-order Elastoplastic Buckling Analysis on Urban Railway Steel-box Overcrossing Structures——Focusing on Pedestrian Overpass Structures

作　　者：曹珂 CAO Ke(China Railway Siyuan Survey And Design Group Co., Ltd, Wuhan 430063)

机构地区：[1]中铁第四勘察设计院集团有限公司

出　　处：《福建建筑》2019年第5期75-79,共5页Fujian Architecture & Construction

摘　　要：钢箱梁结构因其跨越能力强、造型灵活度高的优势,越来越多地应用于城市轨道交通建设中。然而,目前对于城市轨道交通人行钢箱梁天桥结构的稳定性研究十分缺乏,为钢箱梁的工程应用带来不利影响。文章结合新版钢结构设计标准的设计理念,基于二阶弹塑性分析,对钢箱梁结构的稳定性进行了研究。研究得出了钢箱梁结构的失稳形态,通过对比不同初始几何缺陷幅值下结构的极限承载力,提出了保障钢箱梁结构刚度与稳定性的设计建议。Steel-box structures will be increasingly used in the urban railway systems, by the structural and architectural advantages.However, research on buckling behavior of such structures were rarely reported, which provided difficulties on applications of steel-box pedestrian overcrossing structures.In this paper, combined with design method from the new Standard for Design of Steel Structures, eigenvalue buckling analysis were employed, which found the local buckling behavior of bridge deck plates determines the stability of the steel-box overcrossing structure.Furthermore, second-order elastoplastic buckling analysis were employed, and contrastive analysis on the ultimate bearing capacties of steel-box overcrossing with different initial deformations were taken place.It is found that, the elastoplastic bearing capacities were much lower than the elastic critical capacity, and initial imperfections of bridge deck plates affect the ultimate bearing capacities of steel-box overcrossing structures obviously.On these foundations, design suggestions were proposed.

关 键 词：钢箱梁天桥 二阶弹塑性 屈曲分析 初始缺陷 

分 类 号：U213.2[交通运输工程—道路与铁道工程]