Spatial failure mechanism of coastal bridges under extreme waves using high-efficient pseudo-fluid-structure interaction solution scheme

Coastal bridges serve as lifelines in evacuation and rescue after coastal natural hazards. It is thus vital to reveal the spatial failure mechanism for coastal bridges under extreme waves. In this study, a high-efficient pseudo-fluid-structure interaction (PFSI) solution scheme is proposed to investigate the spatial failure mechanism of coastal bridges under extreme waves. A series of laboratory experiments and numerical simulations are conducted to verify the proposed solution scheme. The results solved by the proposed solution scheme are acceptable and reliable under the small rotation of the deck, which could be used to efficiently assess the deck failure, and the calculation process is high-efficient. The spatial failure mechanism of the typical coastal bridge is investigated by using the proposed solution scheme in this study. The properties of wave forces on the deck are discussed based on numerous experimental measurements considering various wave parameter combinations and inundation conditions firstly. Subsequently, the failure thresholds of bearing vertical and horizontal reaction forces are obtained by parametric analysis considering various wave parameter combinations using the proposed solution scheme. Additionally, two typical failure modes (i.e., fall-beam failure and overturning failure) are analyzed by considering time-varying restraining stiffnesses in vertical and horizontal directions. The obtained results can be served as a robust reference for the design and management of coastal bridges under extreme waves.