桥梁断面颤振导数识别的耦合自由振动方法  

Coupled free vibration technique for identifying flutter derivatives of bridge decks

作　　者：丁泉顺[1] 王景[1] 朱乐东[1] 

机构地区：[1]同济大学土木工程防灾国家重点实验室,上海200092

出　　处：《振动与冲击》2012年第24期5-8,25,共5页Journal of Vibration and Shock

基　　金：国家自然科学基金面上项目(51078275;50738002);土木工程防灾国家重点实验室自主研究课题基金(SLDRCE09-B-05)联合资助

摘　　要：通过对系统复模态的特征分析发现,只要给定一个折减风速,就可以唯一地确定出系统的振动模态参数;反之,如果已知某一折减风速(或折减频率)时系统的振动模态参数,将可以确定出对应于该折减风速的桥梁断面各颤振导数。基于该思想,建立了从系统振动模态参数确定桥梁断面颤振导数的方法,该方法理论严密,并根本上克服了现有耦合自由振动颤振导数识别方法存在的缺陷。通过数值算例对该桥梁断面颤振导数识别方法的可靠性和适用性进行了有效的验证,且该识别方法能够对桥面颤振发散后的颤振导数进行识别。Based on complex model analysis of a system, it was shown that the complex modal parameters of the system can be computed from a characteristic analysis when the reduced wind velocity is known; on the contrary, the corresponding flutter derivatives of bridge decks can be determined in a unique manner if the complex modal parameters of the system at one reduced wind velocity （or reduced wind frequency） are known. Based on this idea, a new method identifying the flutter derivatives of bridge decks from the complex modal parameters of the system was proposed and it was theoretically exact and could overcome the main shortcomings of the existing method. The reliability and applicability of the proposed method were verified with numerical examples and it could work even when the flutter occurred.

关 键 词：桥梁断面 颤振导数 耦合自由振动 参数识别 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]