Analysis and Design Approaches for the Transition Zone between Bridges and Embankments in Railway Tracks

This study presents an analysis of stability improvement methods for the transition zone between bridge structures and embankments in railway systems using the Finite Element Method (FEM) model. The study aims to provide guidelines for designing such transition zones. The three methods investigated are recommended by the International Union of Railways (UIC) standard 719R: 1. Société Nationale des Chemins de fer Français method (SNCF), 2. Magyar Államvasutak method (MAV), and 3. Deutsche Bahn method (DB). Initially, the interaction between the rail and bridge models was calibrated using the E1-3 case from the UIC 774-3, which yielded results close to the reference values. Additionally, it was found that analyzing the sequence of applied loads provides better results than directly combining the responses from each load type. Subsequently, the study examined the stability improvement of the transition zones using the rail properties from the UIC 54 and the load standards from U20, which are applicable in Thailand. The analysis revealed that all three methods effectively reduced settlement in the transition zone, with the DB method achieving the highest reduction at 36.18%, and the SNCF and MAV methods achieving an equal reduction of 32.89%. However, considering both settlement reduction and construction techniques, the SNCF method is recommended as the most suitable approach for the design and construction to improve the stability of transition zones.