摘要
为减少城市交通系统运行所衍生的低频振动对人体和建筑物的影响,改善浮置板的动力特性,提高其对低频振动的隔振效果是目前亟待解决的问题.基于双层Euler-Bernoulli梁理论,给出了浮置板轨道结构在移动荷载作用下的耦合动力学分析模型.通过双重Fourier变换将浮置板轨道系统在空间-时间域函数的微分方程转化波数-频率域函数的代数方程,求解频散曲线,分析荷载移动速度对频散特性的影响.然后使用围道积分法进行Fourier逆变换,将波数-频率域内动挠曲线位移解转换为空间-时间域内的解,求得浮置板轨道系统传递到基础的力,评价不同参数变化时浮置板的隔振范围和隔振性能.结果表明当荷载移动速度到达临界速度时,浮置板系统变形将趋向或处于失稳状态;在本文给出的浮置板单位长度质量、板下支承刚度和支承阻尼参数建议值范围内,对改善浮置板低频隔振性能效果显著.
In order to attenuate low frequencies vibrations induced by metro trains and reduce the influence on inhabitants and building nearby the traffic route, it becomes important to improve the dynamic characteristics and vibration isolation performance of floating slab track （FST）system under low frequencies excitation. In this paper, a double-beam model on rigid foundation subject to a low frequencies excitation is employed to assess vibration isolation performance of FST system with various parameters. By means of moving coordinate and Fourier transformation method, the differential equations of FST system are established and solved in the wavenumber-frequency domain for dispersion analysis. The contour integration method is used to convert the responses of the track system from wavenumber-frequency domain into spacetime domain. The forces transmitted to the foundation are obtained to assess vibration isolation range and vibration isolation effectiveness of the track with various parameters. The result demonstrates that deformation of FST system tends to create instability when load velocity approaches to＇ the critical load velocity. For the desirable vibration isolation effectiveness and reasonable cost, value ranges of parameters （mass of slab, stiffness and damping of bearing） are given to provide reference for the design.
出处
《西安建筑科技大学学报（自然科学版）》
CSCD
北大核心
2009年第5期683-688,共6页
Journal of Xi'an University of Architecture & Technology(Natural Science Edition)
基金
西安市科技局基金项目(YF07207)
作者简介
袁俊（1983-），男，四川人，博士研究生，主要从事工程抗振（震）、减振研究。
