【作者】 占冠元；

【导师】 肖亚明；

【作者基本信息】 合肥工业大学 ， 结构工程， 2009， 硕士

【摘要】 近年来,冷弯薄壁型钢在实际工程中的应用越来越广泛,板件越来越薄,在不大的压力作用下,较容易发生局部屈曲,为了增强板件局部稳定性能,通常将截面板件弯折成各种各样复杂加劲类型的板件,从而使得冷弯薄壁构件截面变得越来越复杂。畸变屈曲,作为一种可能控制构件承载力的重要屈曲模式,受到越来越多的研究人员的高度关注,了解畸变屈曲乃至其与其它屈曲模式的相关屈曲的基本性能,对于工程设计与应用有着十分重要的作用。为了探讨研究冷弯薄壁卷边槽钢构件受压畸变屈曲性能,论文首先阐述了关于板件考虑屈曲后强度的两种计算冷弯薄壁卷边槽钢构件承载力的计算方法,比较了中外规范关于有效宽度法的计算思路,引入了国外规范关于直接强度法的计算理论和设计方法,指出直接强度法对于计算截面形状较为复杂、构件可能发生畸变屈曲的冷弯薄壁卷边槽钢构件具有一定的优越性;然后通过有限元方法和有限元软件ABAQUS对冷弯薄壁卷边槽钢受压构件进行了模拟分析,并对影响畸变屈曲性能的一些重要参数进行了详细的分析比较,得出一些较为重要的结论,可供后续研究参考;基于上述的有限元分析,最后提出一种预防加固控制措施,即通过沿构件长度方向设置一定数量的隔板,经过有限元模拟分析的结果表明:这种加设隔板的方式对于控制构件发生畸变屈曲的过大变形和构件的承载力的提高起到了显著的作用,同时还对加设隔板的冷弯薄壁卷边槽钢受压构件进行了畸变屈曲参数的探讨与分析,总结出一些规律,为后续研究乃至工程应用起到了一定的积极推动作用。更多还原

【Abstract】 In recent years, the cold-formed steel has been more and more popular in building constructions. With the cold-formed steel members tending to higher strength, thinner and more complicate shape sections, distortional buckling, as an important strength-governing mode, has become an important research topic recently. It is very important for reseachers to study more on distortional buckling.In this study, firstly, three buckling modes of cold-formed lipped channels are emphasized, and the fundamental concepts and differences of the two methods mentioned above in Chinese and North American codes are compared, and the calculating process of the Direct Strength Method using the complete cross-section of the cold-formed steel members is illustrated. It indicates that the Direct Strength Method provides an entirely new and effective calculating method to design those cold-formed steel members with complex lipped channels, and their load-carrying capacity maybe governed by distortional buckling.Secondly, study on the behavior of distortional buckling through finite element analysis is carried out, and some finite element models are established using the software ABAQUS. Besides, some impact factors are investigated, and gained a lot of useful conclusions.Finally, one kind of strengthing measures is brought up, that is to say, to put several diaphragms along the channel can improve the buckling loads and the ultimate strength. And it is verified through finite element analysis.更多还原