变截面大尺度多开孔钢梁结构性能研究  

Structural performance research of variable cross-section large-scale multiple web-opening steel beams

作　　者：颜阳 王逸飞 范余华 童乐为[2] 宁鹏 YAN Yang;WANG Yifei;FAN Yuhua;TONG Lewei;NING Peng(China Railway Shanghai Design Institute Group Co.,Ltd.,Shanghai 200070,China;College of Civil Engineering,Tongji University,Shanghai 200092,China;Nanjing Railway Hub Project Construction Headquarters,China Railway Shanghai Group Co.,Ltd.,Nanjing 210042,China)

机构地区：[1]中铁上海设计院集团有限公司,上海200070 [2]同济大学土木工程学院,上海200092 [3]中国铁路上海局集团有限公司南京枢纽指挥部,南京210042

出　　处：《建筑结构》2022年第19期105-111,117,共8页Building Structure

基　　金：中国铁路上海局集团公司科研计划(2020141);中铁上海院集团科研计划(集-20-63)。

摘　　要：某高铁线下站房的钢结构屋盖选用了超出设计标准规定的变截面、腹板大尺度多个开孔的钢梁,有必要对其承载能力和延性等性能进行研究。通过试验和有限元分析,研究了开孔梁荷载挠度关系、空腹截面应力分布,对比了空腹桁架理论、试验和有限元计算结果。进一步运用有限元软件ABAQUS对变截面大尺度开孔梁进行了特征值屈曲分析,并进行了考虑不同幅值、不同分布形式的初始几何缺陷在全跨活荷载和半跨活荷载作用下的几何、材料双非线性分析,得到了不同特征的破坏模式。研究发现:大尺度开孔梁弹性设计时,可用费式空腹桁架理论进行验算;大尺度多个开孔梁非线性效应影响显著,在设计时,应充分考虑结构的非线性特征;在全跨活荷载作用下,开孔梁的安全系数可达到2.8,具有良好的承载能力;不同分布形式的缺陷会显著影响大尺度开孔梁的承载力和延性;全跨活荷载比半跨活荷载对变截面大尺度开孔梁的性能更为不利;引入第1阶屈曲模态分布形式的缺陷不一定是最不利的缺陷分布形式,不同的缺陷会造成4种不同的破坏模式。The steel structure roof of a station building under a high-speed railway line uses steel beams with variable cross-sections and large-scale webs with multiple openings which exceed the design standards. It is necessary to analyze its bearing capacity and ductility. The load-displacement relationship and stress distribution of web-opening beams were studied by experiment and finite element, and the results of vierendeel truss theory, experiment and the finite element analysis were compared. The eigenvalue buckling analysis of variable cross-section large-scale web-opening steel beams was carried out using finite element software ABAQUS. Considering the initial geometric imperfection of different amplitudes and distribution forms under full-span live load and half-span live load, the geometric and material nonlinear analysis were carried out, and different characteristics of the failure mode were obtained. The study found that: in the elastic design of large-scale web-opening beams, vierendeel truss theory can be used for calculation;the nonlinear effect of web-opening steel beams has significant influence, and the nonlinear characteristics of the structure should be fully considered in the design;under full-span live load, the safety factor of the steel beams with opening can reach 2.8, and it has a good load-bearing capacity;the imperfection of different distributions will affect the load-bearing capacity and ductility of the web-opening beam, full-span live load is more unfavorable to the performance of the variable cross-section web-opening steel beams than half-span live load;imperfection introduced into the first-order buckling mode distribution form is not necessarily the most unfavorable form of imperfection distribution, different imperfection will cause four kinds of different failure modes.

关 键 词：变截面钢梁 大尺寸矩形孔腹板 缩尺试验 特征值屈曲分析 非线性有限元分析 承载力 延性 

分 类 号：TU391[建筑科学—结构工程]