A comparative study on the running safety of trains subjected to crosswinds simulated with different wind models

Abstract

This article presents a study on the train stability against crosswinds simulated with different wind models. The work focuses on the evaluation of derailment indexes, which are dependent on the wheel-rail contact forces obtained through dynamic analyses performed with a vehicle-structure interaction methodology. The results obtained using the normative European Committee for Standardization (CEN) Discrete Gust model are compared with those obtained with a turbulent wind model based on stochastically generated wind fields. The calculations are performed considering several heights above the terrain to simulate the behaviour of a train running over a bridge deck located at different elevations. The CEN Discrete Gust model proved to be inaccurate and increasingly conservative, in relation to the Turbulent Wind model, as the height above the ground increases, since the former is based on a fixed turbulence intensity corresponding to the ground level, while the latter considers the correct turbulence intensity dependent on the deck elevation. Based on these results, the present article describes an alternative discrete gust approach that takes into consideration the variable turbulence intensity and terrain category in order to improve its applicability in the evaluation of the train running safety on bridges with decks located at different heights.