U形截面圆弧拱平面外稳定性研究  

Study on out-of-plane stability of U-Section circular arch

作　　者：惠宽堂[1] 李瑾[1] 樊军建 

机构地区：[1]西安建筑科技大学土木工程学院,陕西西安710055 [2]西安有色冶金设计研究院,陕西西安710001

出　　处：《空间结构》2014年第2期71-76,96,共7页Spatial Structures

基　　金：陕西省教育厅重点实验室科学研究计划基金资助项目(2012CB723302)

摘　　要：用BEAM 188梁单元和SHELL 181壳单元建立了两种可考虑荷载作用位置的有限元模型,相互验证了模型的正确性.通过对两种荷载模式下U形截面无铰和两铰圆弧拱计算结果的比较,研究了支座类型、荷载模式和矢跨比对钢拱平面外屈曲的影响.对于理想的支座约束,发现径向均布荷载作用下两铰拱平面外屈曲荷载与无铰拱相同,竖向均布荷载作用下两铰拱平面外屈曲荷载在较大矢跨比时明显高于无铰拱;由于两铰与无铰拱的支座构造不同,满足什么条件平面外约束可按无铰对待有待研究.通过对加缀板与加隔板U形截面两铰圆弧拱平面外屈曲荷载的比较,发现加缀板形成间断闭合截面对屈曲荷载提高更显著,且用料少、施工简单.Two kinds of finite element model which can take loading positions into consideration were constructed with BEAM 188 and SHELL 181 element, and the correctness of calculation results is verified by comparing the two models results. Effects of different restraint conditions, rise-span ratios and loading models on out-of-plane buckling are studied by comparing finite element analysis results that the buckling loads of hingeless and two-hinged arches under the radial loading are nearly equal. With bigger rise-span ratio, the out-of-plane stability of two-hinged arches is better than that of hingeless arches under vertical loading uniformly distributed along the arch axis. Because of different constructions of supports, further research should be done to figure out at what conditions the out-of-plane restraints of two-hinged arches can be treated as hingeless arches. By comparing the buckling loads of U-section with diaphragm, a discontinuous-closed cross section with batten plates has higher buckling load with less material, which is simple, economical and easy to construct.

关 键 词：圆弧拱 U形截面 平面外失稳 加缀板 

分 类 号：TU391[建筑科学—结构工程]