Numerical studies of ballastless track-embankment vibrations considering track irregularities

Abstract

High-speed railway systems require precise modelling of track-embankment dynamics to assess structural stability and safety. Existing models struggle to capture the complex nonlinear interactions between trains and track infrastructure. To overcome this limitation, a three-dimensional finite element (3D FE) model was developed to simulate the dynamic responses of track-embankment coupling systems based on the Wuhan-Guangzhou high-speed railway, and it was validated with field measurements. The proposed model innovatively incorporates the geometric complexities of railhead and wheel tread surfaces, along with multiple track irregularities, ensuring realistic simulations. An empirical filtering rule was introduced to address high-frequency numerical noise, enhancing data processing accuracy. The validated model was used to investigate the effects of train speed and track irregularities on the vertical and lateral vibrations of railway system. Results show that vibration intensity rises as train speed increases, with vertical rail vibrations being 1.9 to 2.9 times stronger than lateral vibrations. Moreover, track irregularities amplify embankment vibrations, particularly at higher frequencies and shallower depths, while soil damping mitigates this effect at greater depths. These findings provide valuable insights into the dynamic behaviour of ballastless track-embankment systems and contribute to the development of design and maintenance strategies for high-speed railway infrastructure.