基于功率流法的城市高架轨道振动能量传递特性研究

Research on Vibration Energy Transmission Characteristics of Urban Viaduct Rail Transit Based on Power Flow

近年来,城市高架轨道列车运行过程中产生的振动已成为严重的问题。为研究高架轨道振动能量的传递特性,基于单层隔振系统和多层隔振系统功率流理论,分析振动能量的传递和耗散过程。通过建立高架轨道系统有限元模型,并以实测加速度结果验证模型的准确性。结合有限元模型和功率流理论,分析能量在轨道结构中的分布与传递规律。结果表明:振动能量在轨道结构的固有频率处达到峰值;由于扣件和轨道板支承对振动能量的衰减作用,全频段(1~1000 Hz)范围内,振动能量在从上往下的传递过程中逐渐减小;扣件系统可显著消耗钢轨高频(100~1000 Hz)振动能量,轨道板支承可显著消耗轨道板的低频(1~100 Hz)振动能量;功率流指标能直观反映振动能量在结构中的分布、传递和耗散特性;可通过设计扣件和轨道板支承的刚度和阻尼,获得最优的减振效果。

Recently,the vibration induced by viaduct rail transit has become a severe problem during train operation.To investigate the transmission properties of the vibration energy of the viaduct track,the procedures of transmission and dissipation of the vibration energy are analyzed based on the power flow theory of single-stage and multi-stage vibration isolation system.A viaduct track finite element(FE)model is developed,and the accuracy of the model is verified by observational acceleration.Combined with the FE model and power flow theory,the transmission and distribution characteristics of energy in the viaduct tracks are analyzed.The results show that the peak value of the vibration power is reached at the natural frequency of the track structure;the vibration energy decreases from top to bottom of the track structure in the frequency range of 1~1000 Hz;the fastener system significantly consumes high-frequency(100~1000 Hz)vibration energy and low-frequency(1~100 Hz)vibration energy is significantly consumed by the support of the track slab;the power flow index can indicate the transmission,distribution,and dissipation properties of the energy;and optimal vibration reduction effect can be obtained by designing the stiffness and damping of the fastener system and the support of the track slab.