Frequency Domain Analysis of Train–Guideway Interaction Dynamics

Abstract

A frequency domain approach to dynamic analysis of train–girder interaction is presented. The method is based on the calculation of a harmonic transfer matrix for the system, using the principle of harmonic balance. Results of the analysis are verified by comparison with a numerical integration using Newmark’s method. It is demonstrated that the frequency domain approach is able to model stochastic track irregularity without the need for a Monte Carlo approach, as is required when numerical integration is used. The method also leads naturally to a linear least-squares optimization problem giving the best camber shape for reducing train vibrations. Train vibrations are evaluated using a ride comfort index based on weighted third-octave acceleration magnitudes. Through an illustrative example, it is shown that camber can reduce the total frequency-weighted acceleration level by 22%.