A Hybrid Coupling Approach for Analyzing Soil-Structure-Track-Vehicle Interaction in Railway Bridges Subjected to High-Speed Trains

Accurately predicting the deck acceleration of railway bridges subjected to high-speed trains is essential for maintaining track quality, ballast stability, and the structural integrity of the bridge. This requires modeling the track, bridge, and subsoil in a way that balances accuracy and computational efficiency. The existing literature often reflects this challenge by prioritizing efficiency through simplified assumptions about the foundation, subsoil, track, and bridge structure or accuracy through detailed representations of the geometry and materials of these subsystems. A full, detailed analysis of the structure, subsoil, and train poses a significant computational challenge. This is why such comprehensive models are scarce in the current literature. This study presents a novel algorithm that efficiently includes the complete dynamic train model, fully coupled with the detailed numerical model of the underlying structure and subsoil. The time-integration scheme is based on a localized Lagrange multipliers approach, which is verified against reference computations. An exemplary application examines the interaction effects among the dynamic subsystems of the train, track, bridge, and subsoil.