轨道参数对轮轨耦合系统固有频率的影响

Influence of Track Parameters on Natural Frequencies of Wheel-track Coupling Systems

轮轨系统固有振动特性对车轮失圆和钢轨波磨的形成和发展具有重要影响。建立普通短轨枕整体道床轨道有限元模型和簧下质量-轨道耦合系统有限元模型,分析扣件刚度、地基刚度、簧下质量及轨枕间距对轨道和耦合系统固有频率的影响。结果表明:轨道1阶垂向弯曲频率随扣件刚度的增大而增大,地基刚度对轨道1阶垂向弯曲频率的影响较小;耦合系统1阶垂向弯曲频率(P2共振频率)随扣件刚度的增大而增大,随簧下质量的增大而减小;P2共振频率随地基刚度的增大而增大,当地基刚度大于300MPa/m,地基刚度的变化对P2共振频率影响较小;扣件刚度和地基刚度不变的情况下,轨道1阶垂向弯曲频率和P2共振频率随轨枕间距的增大而减小;轨枕间距随机变化可降低Pinned-Pinned共振响应峰值。通过现场力锤敲击与车辆轨道振动测试结果对模型进行验证,仿真结果与现场测试结果基本一致。

The natural vibration characteristics of wheel-rail system have an important influence on the formation and development of wheel out-of-roundness and rail corrugation.In this study,the finite element model of a monolithic bed track with short sleepers and the finite element model of unsprung mass and track coupling system are established respectively.The effects of fastener stiffness,foundation stiffness,unsprung mass and sleeper spacing on the natural frequencies of the track and the coupling system are analyzed.The results show that the first-order vertical bending frequency of the track increases with the increase of fastener stiffness,and the foundation stiffness has little influence on the first-order vertical bending frequency of the track.The first-order vertical bending frequency (P2 resonance frequency) of the coupling system increases with the increase of fastener stiffness and decreases with the increase of unsprung mass.The resonance frequency of P2 increases with the increase of foundation stiffness.When the foundation stiffness is greater than 300 MPa/m,it has little effect on the P2 resonance frequency.for certain fastener stiffness and foundation stiffness,The first-order vertical bending frequency of the track and the P2 resonance frequency decrease with increasing the sleeper spacing.The random variation of the sleeper spacing can reduce the peak value of pinned-pinned resonance response.The model is validated by the results of field hammering impact test and track vibration test.