摘要
冷弯薄壁型钢截面构件制作简易且材料利用效率高,被广泛应用于建筑结构中。此类钢构件一般较为细长,在工程应用中易发生屈曲,且失稳模态也较为复杂。目前的稳定性设计方法主要是基于线弹性分析并结合经验修正公式进行设计,通常较为保守。此外,冷弯薄壁构件也常采用非对称异形截面,而这类截面的典型特点就是剪切中心和几何中心并不重合。若采用基于对称截面假定(即"两心"重合)的传统梁柱单元来分析此类构件,则会高估其屈曲承载力。为此,引入了基于含翘曲自由度及非对称截面假定的新型翘曲梁柱单元,提出适用于各类复杂异形截面冷弯薄壁型钢构件的稳定性分析理论。该方法可在分析中直接检验构件的稳定性,无需采用计算长度等经验性的假定。阐述了所提出的稳定性设计理论,并介绍了新型翘曲梁柱单元的推导过程和异形薄壁截面的分析方法。最后通过算例,验证了所提出的稳定性设计理论的准确性和适用性。
Cold-formed thin-walled open-section members are extensively used in constructions due to the material efficiency and ease of manufacturing.Such members are usually slender and susceptible to buckling, where the buckling modes are usually coupled and complicated.Current stability method is based on the linear elastic analysis method associated with the use of empirical formulations, which is usually conservative.Further, asymmetric shapes are commonly fabricated for cold-formed sections, where the shear center and the geometric center are not coincident.When using the conventional beam-column elements with the symmetric section assumption, the error in the prediction of buckling strengths can be quite large.A new type of beam-column element with warped degree of freedom and asymmetric section assumption is introduced, and the stability analysis theory for various kinds of cold-formed thin-walled steel members with arbitrarily-shaped section is proposed.This method can directly capture the buckling behaviors of thin-walled members, eliminating the needs in adopting the empirical assumptions, such as the effective lengths.This paper briefly explains the proposed stability design theory, the derivation procedure of the new warping beam-column element and the cross-section analysis algorithm.Finally, several examples are provided for validating and verifying the proposed method for the stability design of cold-formed thin-walled open-section members.
作者
高文龙
万建宏
刘思威
GAO Wenlong;WAN Jianhong;LIU Si-wei(School of Civil Engineering,Sun Yat-Sen University,Guangzhou 519082,China)
出处
《建筑钢结构进展》
CSCD
北大核心
2021年第5期53-62,72,共11页
Progress in Steel Building Structures
基金
中山大学科研启动金(76140-18831105)。
关键词
冷弯薄壁型钢
稳定性
异形截面
梁柱单元
屈曲
数值方法
cold-formed thin-walled steel
stability
special-shaped section
beam-column element
buckling
numericalmethod
