Experimental study on the dynamic responses of the end-anchored floating bridge subjected to joint actions of earthquakes and water waves

This study experimentally investigates a dynamic behavior of an end-anchored floating bridge under the joint actions of earthquakes and water waves. A truncated model with a geometrical scale of 1:100 was utilized for the hydrodynamic test, and an actuator was used to generate the earthquake input. A series of trials were conducted for the floating bridge model under the combined action of two different sea states and three earthquake inputs with increasing intensity based on the concept of the incremental dynamic analysis method. For comparison, the dynamic responses of the floating bridge model under earthquake action in still water and pure wave action were also conducted. Based on the test data, the dynamic responses, particularly focused on the sway, heave, roll, and pitch motions of the pontoons, of the test model were experimentally analyzed. The experimental results showed that earthquake excitation along the longitudinal axis of the bridge girder would induce noticeable oscillation of the bridge pontoons in still water. The magnitude of the coupled effects of earthquakes and water waves is dependent on the intensity of the earthquake inputs and the sea state.