浮置板轨道动力响应分析的广义波数法  

Generalized Wavenumber Method for Dynamic Response Analysis of Floating Slab Track

作　　者：刘维宁[1] 马龙祥[2,3] 姜博龙 王文斌[4] 

机构地区：[1]北京交通大学土木建筑工程学院,北京100044 [2]西南交通大学土木工程学院,四川成都610031 [3]西南交通大学交通隧道工程教育部重点实验室,四川成都610031 [4]中国铁道科学研究院城市轨道交通中心,北京100081

出　　处：《中国铁道科学》2016年第1期31-38,共8页China Railway Science

基　　金：国家自然科学基金资助项目(51278043);中央高校基本科研业务费专项资金资助项目(2682015BR019);中国铁道科学研究院行业服务技术创新项目(2014YJ005)

摘　　要：为求解固定谐振荷载激励下浮置板轨道的动力响应,引入广义波数,将浮置板轨道视为无限长的周期性结构,并在广义波数域内将其在固定谐振荷载激励下的动力响应映射到轨道的1个几何周期范围内,通过求解该几何周期范围内的轨道动力响应进而得到无限长轨道的动力响应.运用提出的方法计算和分析浮置板轨道的动力特性,结果表明：浮置板轨道存在明显的板端效应,即固定谐振荷载激励下引发的振动沿轨道纵向传播时,轨道板板端处的动力响应出现放大现象,其数值甚至大于同一位置处钢轨的动力响应;由固定谐振荷载引发的沿轨道纵向传播的振动在传播过程中的衰减随固定谐振荷载激励频率的不同而不同,频率在0～8及40～1 000 Hz频段内的固定谐振荷载所引发的振动衰减较快,而频率在8～40 Hz频段内的荷载所引发的振动衰减相对缓慢.Generalized wavenumber was introduced to solve the dynamic response of the floating slab track （FST） under the excitation of fixed harmonic load. FST was regarded as an infinite and periodic structure, and the dynamic response under the excitation of fixed harmonic load was mapped into a single geometric period of track in generalized wavenumber domain. Then the dynamic response of infinite track could be obtained through solving the track dynamic response in the geometric period. The proposed method was a- dopted to calculate and analyze FST dynamic characteristics. The results show that significant slab end effect exists in FST structure, i. e. , under the excitation of fixed harmonic load, the dynamic response at the end of slab will appear amplification phenomenon in the propagation of vibration along the longitudinal direction of track, and it even becomes greater than that of rail at the same location. The attenuation of vi- bration caused by fixed harmonic load along the longitudinal direction of track differs with the excitation frequency of fixed harmonic load during propagation process. The vibration attenuation induced by fixed harmonic load is faster when the frequency is in the bands of 0～8 and 40～1 000 Hz, but is relatively slow when the frequency is in the bands of 8～40 Hz.

关 键 词：浮置板轨道 动力响应 谐振荷载 广义波数 

分 类 号：U213.21[交通运输工程—道路与铁道工程]