【作者】 刘合旭；

【导师】 刘来君；

【作者基本信息】 长安大学 ， 桥梁与隧道工程， 2011， 硕士

【摘要】 最近几十年来,随着桥梁结构逐渐的轻柔化、车辆速度和载重的不断增大,车桥耦合振动问题愈加突出。由于公路桥梁结构型式的多样化和汽车荷载的复杂性及不确定性,使得公路桥梁因车辆过桥而引起的耦合振动分析更加复杂。目前国内、外已有车桥耦合振动研究成果基本上都集中在铁路等轨道交通桥梁上,关于公路桥梁车桥耦合振动分析理论与方法研究的文献很少,而且研究的对象大多为简单窄梁桥,复杂结构体系如宽幅梁桥较少。随着有限元技术的广泛应用和大型结构分析软件的大量涌现,为研究这种空间受力特征明显的宽幅桥梁提供了一个有利的工具,而采用有限元法对宽幅桥梁结构进行车桥耦合振动分析,具有重要的理论和实际意义。本文在收集、整理有关车桥耦合振动分析资料的基础上,总结讨论了车桥耦合振动分析的基本理论；同时,论述了桥面不平度的特性,并按照GB/T7031-1986利用Matlab编制程求解出了不同路面等级(A、B、C级)的不平度样本值；然后重点论述了研究车桥耦合振动的一种数值分析方法,推导了相应的车辆振动方程,采用Matlab编制了车辆振动方程的求解程序并加以验证,同时通过算例对基于ANSYS和Matlab的车桥耦合振动分析迭代方法进行了验证。按照此方法,以某宽幅连续箱梁桥为例,研究了宽幅连续箱梁桥的车桥耦合振动性能及其影响因素。分析了车辆行驶方式、桥面不平度、横向车道数目和车辆中偏载行驶等因素对桥梁动力响应的影响。从而对宽幅连续箱梁桥的车桥系统耦合振动分析提供一定的科学依据。更多还原

【Abstract】 With the rapid development of traffic system, the speed and the weight of vehicles are significantly increasing, while bridges are becoming larger, lighter and more flexible. As a result, the vehicle-ridge interaction(VBI) cannot be ignored any longer. The dynamic effects of highway bridges, like vehicle-induced-vibrations become more complex, due to the diversities of structure styles of highway bridges and complexities of vehicle loads.The vehicle-bridge interaction(VBI) has been investigated for decades. However, most of the academic achievements regarding to VBI are about the railway bridges. In terms of highway bridges, there are only some progresses which only refer to the narrow bridges, like the narrowed simply supported girder bridge or the narrowed continuous beam bridge. There are still many aspects regarding wide deck bridges which are unknown. The study on the vehicle-induced-vibrations of wide deck bridges has very important academic significance and practical value.Firstly, this paper summarises the basic theory regarding to the coupling vibrations of vehicle and bridges. Then, the random road surface roughness is explained detailedly in this paper and simulated in Matlab according to the GB/T7031-1986. In the meanwhile, the methods of numerical analysis for the VBI are investigated, and the vibration equations for vehicle are deduced. Moreover, a program is coded in Matlab with Wilson’sθmethod, in order to solve dynamic equations of vehicle, and is proved to be accurate. Also, the numerical analysis method of investigating the VBI is proved to be right through a concrete example. Finally, the vehicle-induced-vibrations of a wide continuous box-girder bridge, which is located in Xi’An, are investigated by this method. In this research, the effects of the driving way of vehicle, the random road surface roughness and the numbers of traffic lane, etc. on dynamic responses of the wide continuous box-girder bridge are studied.更多还原