Modeling method and application of vehicle-track system based on generalized Rayleigh-Ritz method and component mode synthesis

The railway track, as a long-scale composite structure, exhibits significant non-uniformity or randomness in its material properties and the state of its underlying foundation support. In this paper, based on the theory of vehicle-track coupling dynamics, a model for vehicle-track dynamic interaction is constructed using a generalized Rayleigh-Ritz method and component mode synthesis. This model is particularly suited for conditions where the structural cross-section size and material stiffness properties are non-uniform. The study begins with the track structure as the subject of research. An improved Fourier series is chosen as the displacement basis function for the track structure. The modal analysis of the track substructures is then conducted using the variational method of energy functionals, followed by truncation of these modal forms. The boundary conditions between each substructure of the track are integrated to reduce the overall system matrix of the track. For the first time, the GRRM-CMS is applied to analyze the vehicle-track dynamic interaction model. The model’s accuracy is validated by comparing its dynamic response results with those obtained from a FEM-based vehicle-track coupling model. The impact of the number of truncated terms in the track’s basis functions and the selected modal order on the convergence of the dynamic response is quantified. Finally, several examples are presented to demonstrate the model’s capability to perform vehicle-track coupling dynamics analysis under various non-uniform conditions of track structure parameters. The model proves to have considerable engineering reliability and applicability. This approach allows for a more efficient and accurate analysis of complex railway systems, especially in scenarios where traditional methods might fall short due to the inherent non-uniformity and randomness of track properties. © 2024 Chinese Academy of Sciences. All rights reserved.