Stochastic Response of a Coastal Cable-Stayed Bridge Subjected to Multi-Dimensional and Multi-Supported Earthquake and Waves

In this paper, a stochastic dynamic analysis method for cable-stayed bridges subjected to multi-dimensional and multi-supported earthquake and waves is established based on the pseudo-excitation method. The Monte Carlo method is used to analyze the influence of excitation nonlinearity on the bridge structure response, and the applicability of this method is verified. Stochastic response characteristic of coastal cable-stayed bridges subjected to multi-dimensional and multi-supported earthquake and waves is studied. The influence of water–structure interaction on the stochastic seismic response of main components of the cable-stayed bridge is described, and the influence of key parameters is analyzed. The results show that the influence of excitation nonlinearity on the response of the cable-stayed bridge can be neglected. A greater energy input caused by the rigid additional mass of the hydrodynamic pressure is the reason for the increasing of the seismic response. The influence of stochastic response of the underwater structure of the tower is changed with the site conditions. For the ground motion acceleration input energy being distributed in the high-frequency domain, the water–structure interaction has a greater effect on stochastic seismic response of the underwater structure of the tower. The influence of water–structure interaction on the stochastic seismic response of the underwater structure of the cable-stayed bridge increases with the increasing of the wave height and water depth.