Vehicle-bridge coupling dynamic response of sea-crossing railway bridge under correlated wind and wave conditions

The sea-crossing railway bridge is exposed to a high risk of wind and wave, which threatens the safety of the bridge and railway. A wind-wave-vehicle-bridge dynamic analysis model for sea-crossing railway bridge under wind and wave loadings is developed by extending the previous wind-vehicle-bridge model. The developed wind-wave-vehicle-bridge model involves multipoint fluctuating wind field, irregular wave field, finite element model of the bridge, and mass-spring-damper model of the vehicle. The correlation between wind and wave is considered by an empirical curve derived based on field measurement. Static, buffeting, and self-excited wind forces on the bridge and vehicle are considered with coefficients obtained from wind tunnel tests. The wave forces on the bridge are calculated by Morison equation including stretching modification. The governing equations of the wind-wave-vehicle-bridge model are solved in time domain by Newmark-beta method to compute the dynamic response of bridge and vehicle. The dynamic response of bridge and vehicle is compared and discussed in both wind-wave-vehicle-bridge and wind-vehicle-bridge model. The performance of bridge and vehicle are finally evaluated. Studies of dynamic response under correlated wind and wave are found to be imperative for assessment of structural and vehicle safety and driving comfort of sea-crossing railway bridge.