Numerical study of the unsteady crosswind response of high-speed train under local structure-induced unsteady winds by MBS

Unsteady winds induced by structures installed along railway lines pose a threat to train safety, since they generally amplify the unsteady crosswind response. In this study, the dynamic amplification factor (DAF) and characteristic wind curves (CWCs) of a high-speed train under local structure-induced unsteady winds, such as tunnel exit winds, impulse-type gust winds, and step-type gust winds, are studied by using multibody simulations (MBS). First, a 42 DoFs train model is built and verified by numerical simulation results. Second, the DAF of a high-speed train under unsteady wind scenarios is calculated, and it is obvious as the passing time becomes smaller than 2.5 s. A linear increase of the DAF is observed when the high-speed train is subjected to tunnel exit winds or step-type gust winds. While the DAF increases initially, afterwards it decreases as the passing time decreases for impulse-type gust winds. Finally, a simple method to evaluate CWCs of the high-speed train under local structure-induced unsteady winds is proposed using the DAF. In summary, it helps to investigate the wind -induced overturning risk of a high-speed train when passing through the special route in the strong windy areas and to provide the operation control method.