冷弯薄壁卷边槽钢受弯构件畸变屈曲性能研究

发布时间：2018-11-26 14:17

【摘要】：冷弯薄壁型钢因其具有截面特性优良、便于工厂化生产、重量轻等优点而在建筑行业中备受青睐。稳定问题一直以来都是钢结构设计中的核心问题,对于冷弯薄壁型钢构件来说,稳定问题更加重要。冷弯薄壁型钢可能出现的屈曲模式有局部屈曲、畸变屈曲、整体屈曲。随着材料的屈服强度越来越高,构件厚度越来越薄,截面形式日趋复杂,畸变屈曲更容易成为控制构件承载力的屈曲模式。以往对于冷弯薄壁型钢受弯构件畸变屈曲性能的研究,多集中在构件受纯弯作用这一荷载形式,对构件受线性弯矩和翼缘承受均布力等典型荷载形式的研究非常少。为此,本文对受弯构件畸变屈曲的进行更加全面深入的研究。首先,本文选取了经大量研究证实的易发生畸变屈曲的截面,进行了有限元分析,并将分析结果与有限条计算软件计算结果进行对比,误差在5%以内,证实模型建立的有效性,为下一步的有限元研究提供依据。其次,用经验证的有限元模型对冷弯薄壁卷边槽钢受弯构件的畸变屈曲性能进行了分析,包括线弹性分析和弹塑性分析。线弹性分析的主要内容为截面参数及构件长度对受纯弯、线性弯矩、均布力作用的冷弯薄壁卷边槽钢构件畸变屈曲模态、畸变屈曲弯矩的影响,并对比分析了同种截面形式下作用不同荷载形式时,畸变屈曲模态及畸变屈曲承载能力之间的区别和关系。弹塑性分析主要研究了冷弯薄壁槽钢构件的极限承载力,并与直接强度法计算结果进行对比。最后,研究了蒙皮支撑对冷弯薄壁卷边槽钢受弯构件稳定性能的影响。研究内容主要包括蒙皮支撑分别位于构件受拉翼缘、受压翼缘一侧时对槽钢受弯构件稳定性能的影响；有蒙皮支撑的槽钢梁间距不同、根数不同时对槽钢受弯构件稳定性能的影响。而后分析了蒙皮厚度对冷弯薄壁卷边槽形受弯构件稳定性能的影响。
[Abstract]:Cold-formed thin-walled steel is very popular in the construction industry because of its excellent cross-section characteristics, convenient for industrial production, light weight and so on. The stability problem has always been the core problem in the steel structure design, and the stability problem is more important for the cold-formed thin-walled steel members. There are local buckling, distortion buckling and global buckling of cold-formed thin-walled steel. With the increasing yield strength of the material, the thickness of the member becomes thinner and thinner, the form of section becomes more and more complex, and the distortion buckling is more easily become the buckling mode to control the bearing capacity of the member. In the past, the research on the distortion buckling behavior of cold-formed thin-walled steel members was mainly focused on the load form of pure bending, but the research on the typical load forms such as linear bending moment and flange bearing uniform force was very rare. Therefore, the buckling of flexural members is studied more thoroughly in this paper. First of all, this paper selects the section which is proved by a lot of research to be prone to distortion buckling, carries on the finite element analysis, and compares the analysis result with the finite strip calculation result, the error is less than 5%. The validity of the model is verified, which provides the basis for the next finite element research. Secondly, the distortion buckling behavior of cold-formed thin-walled crimped channel members is analyzed by using the verified finite element model, including linear elastic analysis and elastic-plastic analysis. The main content of linear elastic analysis is the effect of section parameters and member length on distortion buckling mode and bending moment of cold-formed thin-walled crimped channel members subjected to pure bending, linear moment and uniform force. The difference and relationship between the mode of distortion buckling and the bearing capacity of distortion buckling are compared and analyzed. The ultimate bearing capacity of cold-formed thin-walled channel members is studied by elastic-plastic analysis, and the results are compared with those calculated by direct strength method. Finally, the influence of skin bracing on the stability of cold-formed thin-walled crimped channel members is studied. The research mainly includes the influence of skin bracing on the tensile flange of the member, and the influence of the compression flange on the stability of the channel steel bending member. The influence of different spacing and root number on the stability of channel beam with skin support is discussed. Then the influence of skin thickness on the stability of cold-formed thin-walled crimped grooves is analyzed.
【学位授予单位】：武汉理工大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU392.1

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