An efficient analysis framework for high-speed train-bridge coupled vibration under non-stationary winds

The consideration of train-bridge system under winds has been attracted extensive attentions, but the winds are typically treated as stationary. This stationary assumption clearly presents a departure from the field observations during extreme storms (e.g., tropical cyclones, thunderstorms and tornadoes). The assurance of structural safety and reliability requires accurate modeling of the non-stationary features in the coupled high-speed train-bridge vibration system. In this study, an efficient analysis framework for high-speed train-bridge coupled vibrations under non-stationary winds based on the pseudo excitation method (PEM) has been developed, in which the non-stationary winds were transformed into a series of pseudoharmonic excitation vectors. The high simulation fidelity and computational efficiency of the established analysis framework were verified based on a case study where the train run over a seven-span continuous girder high-speed railway bridge. A number of transient durations and maximum wind speeds associated with various extreme events are investigated to comprehensively examine the non-stationary effects on the high-speed train-bridge coupled vibrations. It has been demonstrated that the non-stationary characteristics of winds presented important contributions to the dynamic performance of the coupled train-bridge interaction system.