轨道交通槽形梁结构振动与噪声特性研究

Study on structural vibration and noise characteristics of rail transit trough girders

为研究轨道交通槽形梁结构振动与噪声的特性,基于车辆-轨道耦合动力学模型,利用有限元和边界元法分析槽形梁结构的声振特性,得到槽形梁底板的垂向振动加速度振级和腹板的横向振动加速度振级的峰值频率均为63 Hz;槽形梁结构噪声的线性声压级的峰值频率在31.5~80 Hz之间,且离桥梁的距离越远,场点的最大线性声压级越小。研究结果表明:采用固支边界条件的槽形梁结构自振频率较大,且具有显著的减振降噪效果,结果可为轨道交通槽形梁的结构声学优化提供理论参考。

In order to study the characteristics of the vibration and noise of the channel beam structure,the finite element method and the boundary element method were used to analyze the vibration characteristics of the structure on the basis of the vehicle track coupling dynamic model.The vertical vibration acceleration vibration level and the peak frequency of the lateral vibration acceleration vibration level of the channel beam bottom plate were 63 Hz.U-shaped beam linear noise sound pressure level of the peak frequency was between 31.5~80 Hz,and with further distance from the bridge,the maximum linear sound pressure level of points was smaller.In addition,the effect of the boundary condition on the natural vibration frequency of the bridge structure was investigated,and the influence of boundary conditions was analyzed from sound and vibration characteristics of beam structure of groove.Calculation shows that the groove beam structures with the clamped boundary conditions have large vibration frequency,and the fixed boundary condition has a significant effect on the damping groove the noise of the beam structure,which provides a theoretical reference for the acoustic optimization of rail groove beams.