FEM modeling and analysis on the mechanism of vibration reduction of railway with impact absorber

Abstract

This paper is presented a method which can suppress railway vibration using impact absorber. While the traditional dynamic absorber attenuate the vibration mainly at the pre-tuned frequency mode of the rail, impact absorber generates greater damping to reduce all resonant frequency modes of the railway. For analysis and predict the damping effect of impact absorber on the railway, finite element method (FEM) is applied to model. Assuming the rail as Euler-Bernoulli beam which the element mass and stiffness matrices are given. The global matrices can be constituted by element matrices so that the global equation of the system can be expressed. Runge-Kutta method is employed to simulate inelasticity collision between rail and impact absorber. In this way, it's not only able to calculate time and frequency response but also can analyze its sensitivity to variations of the clearance, mass ratio and restitution coefficient. To test the performance, impact absorbers are installed on a 'freely' supported rail and verify the mechanism experimentally. The result can be utilized to reduce the rolling noise from high-speed trains.