肋环形加劲浅球壳缩尺模型的自振特性分析  

Natural Vibration Characteristics of Ribbed Ring Stiffened Shallow Spherical Shell

作　　者：高展 贾冬云[1] 刘健文 王涛[1] GAO Zhan;JIA Dongyun;LIU Jianwen;WANG Tao(School of Civil Engineering and Architecture,Anhui University of Technology,Maanshan 243032,China)

机构地区：[1]安徽工业大学建筑工程学院,安徽马鞍山243032

出　　处：《安徽工业大学学报（自然科学版）》2020年第3期289-294,共6页Journal of Anhui University of Technology（Natural Science）

基　　金：安徽省自然科学基金项目(1708085ME126);安徽工业大学研究生创新研究基金项目(2017060)。

摘　　要：参照直径45 m储气柜顶盖设计肋环形加劲浅球壳缩尺模型,采用模态试验与有限元分析的方法获取肋环形加劲浅球壳结构的自振频率和振型图,分析矢跨比、顶壳厚度、约束形式等对肋环形加劲浅球壳自振特性的影响。结果表明:肋环形加劲浅球壳结构的基频较高、刚度较好、属刚性结构,为以竖向变形为主的对称振型,结构的竖向刚度较弱;有限元分析结果与模态试验结果的前5阶自振频率偏差在10%以内,且前2阶振型吻合较好,说明有限元分析方法可用于分析肋环形加劲浅球壳结构的低阶动力特性;结构基频随矢跨比的减小而减小,支座约束形式对结构频率的影响可忽略,结构基频随顶壳厚度的增加而增加,但增加幅度逐渐减小。With reference to the top cover of gasholder with diameter of 45 m, the reduced-scale model of the ribbed ring stiffened shallow spherical shell was designed. The natural frequency and mode shape of the ribbed ring stiffened shallow spherical shell were obtained by modal test and the analysis of finite element. The influences of parameters such as the ratio of rise to span, the thickness of the shell, and the form of constraint on the natural vibration characteristics of the structure were analyzed. The results show that the ribbed ring stiffened shallow spherical shell has a high fundamental frequency, good rigidity, and is a rigid structure. The vertical mode shape indicates that the vertical stiffness of the structure is weak. The deviation of the first 5 order natural frequencies is within 10% between the mode experlmental results and the finite element analysis results, and the first 2 order of mode shapes are in good agreement, which is shown that the finit element analysis method can be used to analyze the low order dynamic characteristics of ribbed ring siffened shallow spherical shell. The fundamental frequency of the structure decreases with the decrease of the ratio of rise to span, and the influence of the restraint form of the support on the frequency of structure is negligible. The fundamental frequency of the structure increases with the increase of thickness of the top shell, but the increasing speed gradually decreases.

关 键 词：肋环形浅球壳 缩尺模型 模态试验 自振特性 有限元分析 

分 类 号：TU392.6[建筑科学—结构工程]