提升钢弹簧浮置板轨道稳定性的抑振调频装置研究

The installation of the vibration frequency modulation device (VFMD) on the track slab is an effective measure to improve the stability of steel-spring floating slab track (FST). Based on the finite element method and vehicle-track coupled dynamics theory, a vehicle-FST coupled dynamics model involving VFMD is developed in this work. The influence of three key parameters, namely stiffness, damping and preload, of the VFMD, on the stability and the damping capacity of the FST, and the running stability of the train is calculated and analyzed. The results show that the VFMD can effectively suppress the vibration of the FST and adjust the natural frequency of the track slab. The frequency response amplitude for the vertical displacement of track slab decreases exponentially with the increase of stiffness and damping of the VFMD, while slightly affected by the preload. The adjustment ability of the VFMD is more obvious and easy to implement in practice when the stiffness varies from 0 to 10 kN·mm^-1 and damping from 0 to 100 kN·s·m^-1. The increase of stiffness, damping and preload of the VFMD can effectively reduce the accelerations of the track and the vehicle system, and the effect of each parameter differs significantly, with stiffness being the most obvious, followed by damping, and preload being smaller. When the VFMD with stiffness of 6. 5 kN·mm^-1, preload of 2 kN and damping of 60 kN·s·m^-1 is installed on the FST, the acceleration of the track foundation is decreased by 74. 5% and 15. 6% compared with that for the damping fastener track and the FST respectively, without the VFMD, which effectively improves the stability of the track system.