大跨径桥梁风致振动实测与研究

发布时间：2018-01-19 10:45

本文关键词： 厦漳大桥风致振动抖振实测　出处：《重庆交通大学》2014年硕士论文　论文类型：学位论文

【摘要】：随着科学技术的发展，桥梁的跨径变得越来越大，桥梁结构越来越长、细、柔和弱阻尼是其发展的必然趋势。导致了桥梁结构对风的动力作用越来越敏感，为了保证桥梁结构的安全性和舒适性，为此对桥梁结构的抗风性能进行分析是非常必要的。本文主要是以一座大跨度斜拉桥——厦漳大桥北汊主桥为研究背景，对其进行风致振动抖振分析和风致振动现场实测，并对两者之间的结果进行对比研究。围绕以上研究主题，本文的研究内容主要如下： ①、回顾了大跨度桥梁的发展历程，，并对其未来的发展趋势做出了展望，然后对桥梁结构的风致振动研究进行了简单的回顾，并介绍了风致振动现场实测的发展以及其必要性。 ②、介绍了风场模拟的两种方法，分别对线性滤波法和谐波合成法的做了简单的介绍。本文根据AR线性滤波法，利用Matlab编制了合适的模拟程序，并利用该程序模拟了厦漳大桥北汊主桥的脉动风风速场。 ③、先是介绍了桥梁风致振动的几种类型，然后对其中的大跨度桥抖振的分析方法进行了归纳总结，最后针对桥梁抖振分析，推导了按照准定常理论桥梁抖振力的计算公式，并根据此计算公式，基于模拟的脉动风风速场，并结合风洞试验结果，模拟了主梁上的抖振力时程。 ④、利用ansys有限元程序，对厦漳大桥北汊主桥进行有限元建模，为了检验模型的正确与否，对该模型进行了动力分析。并把抖振力时程和自激力时程加载到该有限元模型上，进行动力时程分析，求得各个工况下的风致振动响应分析结果。 ⑤、利用实测系统，对厦漳大桥北汊主桥进行了风致振动现场实测，主要进行的是加速度信号的测量，并根据实测数据分析了其动力特性，得到其各阶频率和阻尼比，除此之外还对其进行了时程分析，并与有限元分析得出的结果进行对比研究。最后对相同平均风，但来流方向不同，引起的抖振响应做了对比研究。 ⑥、对本位的研究工作做了总结，给出了一些研究中得出的结论，并对接下来的努力方向做出了一些期许。
[Abstract]:With the development of science and technology, the span of bridge becomes larger and larger, and the bridge structure becomes longer and longer, thin and soft and weak damping is the inevitable trend of its development, which leads to the bridge structure more and more sensitive to the dynamic action of wind. In order to ensure the safety and comfort of the bridge structure, it is necessary to analyze the wind-resistant performance of the bridge structure. The buffeting analysis of wind-induced vibration and the field measurement of wind-induced vibration are carried out, and the results between them are compared. The main contents of this paper are as follows: 1. The development course of the long-span bridge is reviewed, and the future development trend is prospected. Then, the wind-induced vibration of the bridge structure is briefly reviewed. The development and necessity of field measurement of wind-induced vibration are also introduced. 2. Two methods of wind field simulation are introduced, and the linear filtering method and harmonic synthesis method are simply introduced. According to AR linear filtering method, a suitable simulation program is compiled by using Matlab. The pulsating wind velocity field of the north branch main bridge of Xiazhang Bridge is simulated by this program. 3. Firstly, several types of wind-induced vibration of bridges are introduced, then the analysis methods of buffeting of long-span bridges are summarized, and finally the buffeting analysis of bridges is carried out. The formula for calculating buffeting force of bridge based on quasi-steady theory is derived. Based on the formula, the time history of buffeting force on the main beam is simulated based on the simulated pulsating wind velocity field and wind tunnel test results. 4. Using the finite element program of ansys, the finite element model of the main bridge of Xiazhang Bridge is built in order to verify whether the model is correct or not. The time history of buffeting force and the time history of self-excited force are loaded into the finite element model, and the dynamic time history analysis is carried out, and the results of wind-induced vibration response under various working conditions are obtained. 5. The wind-induced vibration of the main bridge in the north branch of Xiazhang Bridge is measured by the measurement system, the acceleration signal is mainly measured, and its dynamic characteristics are analyzed according to the measured data. The frequency and damping ratio are obtained, in addition to the time history analysis, and compared with the results obtained by finite element analysis. Finally, for the same average wind, but the direction of the flow is different. The buffeting response caused by this method is compared. 6. This paper summarizes the research work, gives some conclusions, and makes some expectations for the future efforts.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U441.3

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