为探究高速铁路有砟轨道结构中的弹性波波动行为,基于周期结构理论,采用广义平面波展开法,建立包含道砟在内的三维周期有砟轨道结构模型.然后,进行波叠加法的推导,从试验的角度反演弹性波的传播规律,验证三维轨道模型的正确性.在此基础上,计算并分析结构的能带分布以及道砟结构参数对轨道结构弹性波传播的影响.结果表明:广义平面波解析法与波叠加试验方法得到的能带分布结果基本吻合,所采用的方法正确可靠;三维有砟轨道低频阶段存在0～62,63～138,160～169和181～224Hz共4个局域共振带隙;道砟对轨道结构频散特性的影响主要集中在低频阶段,提高道砟剪切刚度会增强结构在带隙频段内的衰减能力,剪切刚度从50 kN·mm-1增至90kN·mm-1,频带隙的总宽度则从180 Hz减至170 Hz,带隙宽度减小率不断提高;道砟参振质量主要影响2阶、4阶带隙的宽度,单个道砟参振质量考虑为500kg时低频带隙宽度最大,对振动的衰减量也最大,而当它从500kg增至800 kg时低频带隙总宽度则减小8.9 Hz.
Abstract
To investigate the elastic wave behavior in high-speed railway ballasted track structures,this paper uses the theory of periodic structures and the generalized plane wave expansion method to establish a 3D periodic ballasted track structure model that incorporates ballast.Subsequently,the wave superposition method is derived to inversely analyze the propagation of elastic waves from an experimental perspective,thereby verifying the accuracy of the 3D periodic track structure model.On this basis,this research calculates and analyzes the energy band distribution of the structure and assesses the influence of ballast structural parameters on the propagation of elastic waves within the track structure.The results show that the generalized plane wave analysis method proposed in this paper closely aligns with the band distribution results obtained by the wave superposition experimental method.There are four local resonance bandgaps identified:0-62 Hz,63-138 Hz,160-169 Hz and 181-224 Hz,in the low-frequency range of the 3D periodic ballasted track.The influence of ballast on the dispersion characteristics of the track structure is mainly observed in the low-frequency range.The shear stiffness of the ballast will enhance the attenuation ability of the structure in the bandgap frequency band;the shear stiffness will increase from 50 kN·mm-1 to 90 kN·mm-1;the total width of the frequency gap will decrease from 180 Hz to 170 Hz;and the reduction rate of the bandgap width will continue to increase.The participatory mass of ballast significantly affects the width of the second-and fourth-order bandgaps.The total width of the low-frequency bandgap decreases by 8.9 Hz when the participatory mass of a single ballast is considered to be 500 kg,and the maximum attenuation of vibration is obtained;when the mass is increased from 500 kg to 800 kg,the total width of the low-frequency bandgap decreases by 8.9 Hz.
维普
万方数据