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Study on the Analysis and Control Method of the Vibrations and Noises in Highway and Railway Bridges under the Passage of Vehicles

车辆通过的公铁桥梁振动与噪声分析与控制方法研究

基本信息

批准号：
02650322
负责人：
FUKASAWA Yasuharu
金额：
$ 1.28万
依托单位：
Yamanashi University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1990
资助国家：
日本
起止时间：
1990 至 1991
项目状态：
已结题

项目摘要

In the first half of this study, the authors investigated dynamic responses of highway bridges to travelling heavy vehicles and the low frequency sounds radiated from the vibrating bridges. Simply or continuously supported girder bridges were considered. And as models of heavy vehicles, the fourdegree-of-freedom system with two axles were employed. Governing equations of the coupling motions of the bridge and travelling vehicle models were numerically integrated to solve the problem.Using the Fourier spectra of vibration velocities of bridge surface, the SPL of the low frequency sound radiated from the vibrating bridge was analyzed under the assumption in acoustic field that each of infinitesimal elements of the bridge surface may correspond to a sound source in infinite baffle. The effects of unevenness on the surface at bridge ends, span length of the bridge and travelling velocity of the vehicle on the SPL were examined. As the results of these treatments, control methods of the vibrations and noises in highway bridges under the passage of vehicles were clarified.In the latter half, the authors dealt with the impact problems of plate-girders by means of the finite strip method in order to clarify the fundamental characteristics of the vibrations and noises in railway bridges. Firstly, natural vibration modes of high frequencies in I-section and box-section steel girders were analyzed, and the results obtained were showen in dispersion curves of phase velocities. Secondly, dynamic behaviors of I-section steel girders subjected to impact loads were investigated analitically. And numerical solutions obtained for the girders had a good agreement with the experimental results.

在本研究的前半部分，作者研究了公路桥梁对行驶重型车辆的动力响应和振动桥梁辐射的低频声。考虑了简支或连续支承梁桥。作为重型车辆模型，采用双轴四自由度系统。通过数值积分桥梁与行驶车辆模型耦合运动的控制方程，利用桥面振动速度的傅立叶谱，在声场中假定桥面上的每一个微元都对应于无限大隔板中的一个声源的假设下，分析了振动桥梁低频声辐射的声压级。研究了桥头路面不平度、桥梁跨度和车辆行驶速度对SPL的影响。本文还用有限条法对板梁碰撞问题进行了处理，以阐明铁路桥梁振动和噪声的基本特性。首先，对工字形截面和箱形截面钢梁的高频自振模态进行了分析，并给出了相速度频散曲线。其次，分析了冲击荷载作用下工字形钢梁的动力特性。计算结果与试验结果吻合较好。