摩天轮结构风荷载作用下的动力响应分析.pdf

Dissertation Submitted to Shanghai Jiao Tong University for the Degree of Master Dynamic Response Analysis of the Ferris Wheel Structure Under the Fluctuating Wind Candidate : Hou Fengguo Student ID: 1110109123 Supervisor : Chunjiang Assistant Supervisor: Prof. Li Xiangmin Academic Degree Applied for : Master of Engineering Speciality : Structure Engineer Affiliation : School of NAOCE Date of Defence : Jan, 2014 Degree-Conferring-Institution : Shanghai Jiao Tong University 万方数据万方数据万方数据万方数据上海交通大学硕士学位论文 I 摩天轮结构风荷载作用下的动力响应分析摘要摩天轮作为一类巨型高耸结构体系, 其构造方式独特, 受力复杂; 摩天轮结构除了满足一般高层结构的要求外,还要判断其变形及舒适性是否恰当。故不仅要对摩天轮结构进行非线性静力计算,还要满足动力分析的条件。摩天轮结构作为一类特殊的大跨空间结构,其结构的力学特性较传统框架结构以及常见的索结构和空间桁架结构的受力特性有显著的不同,几何非线性效应也非常明显。首先,该类结构体系的风敏感性特别高,由于摩天轮结构的高度一般比较高,底部约束条件比较弱, 所以结构的扭转振动非常显著; 而传统的风荷载计算是不考虑结构的扭转振动,而以弯曲振型为主;而且该类结构的整体振动和局部振动模态糅合在一起,自振频率分布非常不均匀,低阶模态与高阶模态分布会有显著的阶跃现象,按照通常的结构确定振动影响阶次,会有比较大的误差。本文中首先通过对脉动风时程的人工模拟得到复合某类反应谱的风速时程;通过转换为构件表面的风荷载时程,得到摩天轮结构风荷载响应的输入条件,然后在 ANSYS 环境中,对摩天轮结构进行多参数和多风攻角工况下的风荷载动力时程分析。通过对计算结果的比较和归纳,得出该类结构体系的关键设计参数,为该类结构的抗风设计提供依据,对摩天轮结构的风振响应及整体安全性进行全面评估,对该类结构的工程设计和理论分析都有一定的参考意义。关键词: 摩天轮,脉动风,线性滤波法,风振响应,自振特性万方数据上海交通大学硕士学位论文 II DYNAMIC RESPONSE ANALYSIS OF THE FERRIS WHEEL STRUCTURE UNDER THE FLUCTUATING WIND ABSTRACT As a kind of giant towering structure, the ferris wheel structure has plex dynamic response under the wind loading plex construction. The ferris wheel structure should meet not only the displacement requirements for high-rise civil structures, but also the need fort. So it is necessary to perform nonlinear static analysis, and also necessary to do dynamic analysis for the ferris wheel structure. As a very special kind of large-span structure, its mechanics property is totally different with the traditional cable and truss structures; its geometric nonlinearity is very notable; and the fluctuating wind vibration is also serious for most cases. First of all, the dynamic sensitivity of this structure system under wind loading is particularly the view