Probabilistic assessment of the train running safety on a short-span high-speed railway bridge

In this work the running safety of high-speed trains on a short-span bridge is assessed. A probabilistic approach that combines Monte Carlo simulation with the extreme value theory is used and the existence of track irregularities is taken into account along with the variability of parameters related to the bridge, the track and the train. As case study, a 12 m span filler beam bridge was selected as the train–bridge interaction effects are most significant for short spans. The running safety is assessed for the case of loss of contact between the wheel and the rail, taking into consideration only the vertical wheel–rail interaction and assuming that no lateral forces act on the train. This research enables the characterisation of the wheel unloading coefficient, the identification of the critical wheel and also the definition of the maximum allowable speed for trains to run safely on the bridge.