【作者】 杨咏漪；

【导师】 廖海黎；

【作者基本信息】 西南交通大学 ， 桥梁与隧道工程， 2008， 博士

【摘要】 论文首先回顾了大跨桥梁抖振和疲劳频域分析现状以及目前存在的问题,并明确了在频域内快速准确地估算抖振引起的疲劳寿命问题是今后桥梁抖振精细化分析中一个重要的研究方向。本文利用风洞试验和理论分析相结合的方法,对目前大跨度桥梁的风致抖振及其引起的疲劳问题进行了详细和深入地研究。本文的主要研究内容有:1.回顾了抖振的研究历史、现状以及将来的研究方向,分别从频域和时域角度对抖振分析的理论进行了深入论述;2.在研究既有大跨度桥梁非线性分析理论的基础上,提出了空间梁单元的动参考点法,并且用该方法和CR列式法相结合方便快捷地解决了空间梁单元的几何非线性计算问题;3.建立了基于Markov过程的大跨度桥梁风致疲劳频域研究方法,详细论述了其原理和实现过程,并通过实例分析了该算法与其它疲劳算法间的差异;4.指出了桥梁传统软件工程存在的弊端,论述了面向对象软件编制方法的优点,并利用该方法编写了风桥空间耦合振动和随机疲劳分析程序BSANSYS(Bridge Structure Analysis System),及与其配套的基于ObiectARX开发的前处理程序BSCAD;5.以珠江黄浦南汊桥为例,采用BSANSYS软件对该桥进行了抖振时域分析,并充分考虑了几何非线性、气动导纳、自激力、抖振力非线性等因素对结果的影响;通过与风洞试验及抖振频域分析进行比较,验证了结果的可靠性。在抖振分析的基础上,用雨流计数法的频域解评估了南汊桥的疲劳寿命。更多还原

【Abstract】 This dissertation reviews the state-of-art and the potential issues of buffeting and buffeting-related fatigue of long-span bridge. Quick and accurate calculation of the fatigue life caused by buffeting in frequency domain will be an important direction in elaborate analysis of bridges in future. It is the scope of this dissertation to study buffeting of the long-span bridge and buffeting-related fatigue. The main contents are:1. The buffeting analytical theory is explored in time and frequency domains by reviewing the study history and the state-of-art of bridge buffeting.2. On the basis of current non-linear analytic theory for long-span bridge, Moving Reference Point Method is brought forward, which working together with Co-rotational(CR) Formulation, could well tackle with geometrically non-linear analysis for 3-D beam element.3. Research approach in frequency domain for wind-induced fatigue of long-span bridge, based on Markov Process, has been developed. Followed discussion in details on its theory and realization, the approach demonstrates its overriding performance compared with other algorithm on fatigue analysis in sample solution.4. Issues on current bridge engineering softwares are addressed and advantages of OOP(Object-oriented Programming) are discussed. And then enhanced with OOP, BSANSYS(Bridge Structure Analysis System) and ObjectARX-based BSCAD have been developed to well facilitate analysis on wind-bridge coupled vibration and random fatigue.5. The buffeting of Huangpu Nancha Bridge is computed in time domain by using code BSANSYS. The possible influence on buffeting response is investigated by considering geometrically nonlinearity, aerodynamic admittance, motion-excited and buffeting loading. By comparing to buffeting analysis in frequency domain, the validity of the present results is proven. The evaluation of the fatigue endurance of the Nan Cha Bridge is given by rainflow cycle method in frequency domain.更多还原