钢管混凝土圆弧桁架拱平面内徐变稳定分析  

In-plane creep stability analysis for concrete-filled steel tubular circular truss arches

作　　者：董宁娟[1] 刘超[2] 赵洪金[3] 

机构地区：[1]南京航空航天大学机械结构力学及控制国家重点实验室,南京210016 [2]西安建筑科技大学理学院,西安710055 [3]中交第一公路勘察设计研究院有限公司,西安710065

出　　处：《计算力学学报》2014年第5期590-595,共6页Chinese Journal of Computational Mechanics

基　　金：西安建筑科技大学校青年基金(QN0801)资助项目

摘　　要：核心混凝土的徐变会增加钢管混凝土拱肋的屈曲前变形,降低结构的稳定承载力,因此只有计入屈曲前变形的影响,才能准确得到钢管混凝土拱的徐变稳定承载力。基于圆弧形浅拱的非线性屈曲理论,采用虚功原理,建立了考虑徐变和剪切变形双重效应的管混凝土圆弧桁架拱的平面内非线性平衡方程,求得两铰和无铰桁架拱发生反对称分岔屈曲和对称跳跃屈曲的徐变稳定临界荷载。探讨了钢管混凝土桁架拱核心混凝土徐变随修正长细比、圆心角和加载龄期对该类结构弹性稳定承载力的影响,为钢管混凝土桁架拱长期设计提供理论依据。For concrete-filled steel tube arch ribs, the creep of concrete would increase the pre-buckling deformation which will reduce the in-plane buckling resistance significantly, therefore only included in the influence of pre-buckling deformation on the stability behavior,creep stable bearing capacity can be accurately obtained of concrete filled steel tube arches. In this paper, based on the theory of nonlinear buckling of shallow arch, the nonlinear in-plane equilibrium and buckling equations for CFST truss arches are established by using the principle of virtual work. By solving these equations,a-symmetric bifurcation buckling and symmetric snap-through bucking creep stability load are proposed of pin-ended arches and fixed arches,and the effect of core concrete creep on the stability of CFST arches has been studied. In addition, the influence of modified slenderness, central and creep coefficient on creep buckling behaviors has been investigated, providing theoretical basis for long-term design of concrete filled steel truss arches.

关 键 词：钢管混凝土桁架拱 徐变效应 剪切变形 分岔屈曲 跳跃屈曲 

分 类 号：U448.22[建筑科学—桥梁与隧道工程] O344.7[交通运输工程—道路与铁道工程]