Abstract：To analyze the damage mechanics of coastal bridge girders under wave loads induced by the storm surges and the hurricane, a 1∶〖KG-2mm〗30 scale box girder model test was conducted in a wave basin based on the hydrological conditions and the structural parameters of the Pingtan Rail-Road Sea-Crossing Bridge. The influence of three parameters, i.e. bridge elevation, submerged depth and wave height, on the wave forces is studied. The wave force characteristics of the beam under different wave conditions are analyzed, and the variation of the maximum wave forces under different parameters are compared. It is shown that the wave force is composed of the quasi-static force and the slamming force. When the girder is in low submersion, the slamming force will get large and decrease with the submersion depth. When the box girder is submerged, the uplift force acting on the bottom of girder can reduce the effective weight of the girder, thus it fails to work under the combined actions of the horizontal wave force and the overturning moment. The analysis results show that the uplift force reaches the maximum value when the submersion coefficient is 1.5.
