Abstract:To study the seismic response characteristics of curved bridges considering the pile-soil dynamic interaction under a multi-dimensional seismic excitation, a nonlinear theoretical analysis model of pile-soil interaction was established in this paper. To simplify the calculation process, the nonlinear spring model was linearized, and a simulation model of curved bridges on a loess site was established based on the finite element ANSYS analysis platform. A multi-dimensional and multi-condition numerical analysis of curved bridges, in the context of pile-soil interaction, was carried out. Analysis included the seismic response of the midspan bending moment of curved girder, the shear force and bending moment at the bottom of the pier, and the displacement at the top of the pier. The results showed that the midspan internal force of the main girder of the curved bridge, under given pile-soil interaction, was closely related to the direction of seismic wave input, and the internal force of the girder was the largest under three-dimensional seismic action. The radial shear force response at the bottom of the bridge pier was much larger than the tangential shear force response under the seismic load, while the radial bending moment of the bridge pier was slightly smaller than the tangential bending moment. Under the same loading condition, the top tangential displacement responses of different piers were the same, while the radial displacements were quite different. In the seismic design of irregular curved bridges, the input conditions of multi-dimensional and single-dimensional seismic excitation should be fully considered.
