Wheel-rail impact load due to the loss of sleeper-ballast interface

This paper presents a comprehensive study on the simulation and analysis of the loss of sleeper-ballast interfaces in railway systems. Through a combination of Multibody Dynamics (MBD) and Finite Element Analysis (FEA) techniques, accurate modeling and validation processes were employed to investigate the impact of interface loss on wheel-rail impact load. Various scenarios were explored, revealing significant findings: for fewer than 4 sleeper-ballast interface losses, a notable 30% increase in wheel-rail impact load was observed, while the rate of increase in wheel-rail impact load diminished for more than 4 sleepers. Furthermore, gap size emerged as a critical factor, with sizes between 0.2 mm and 1.6 mm leading to a load increase exceeding 65%. The study also highlighted the substantial influence of train speed on load dynamics, particularly evident at speeds up to 200 km/h, where loads escalated significantly, resulting in a 180% increase under adverse conditions. These findings emphasize the importance of considering various factors in maintaining railway infrastructure integrity and safety.