Continuous Rigid-Frame Bridge is a girder bridge with main girder and abutment rigidly connected to form a rigid frame, which has the advantages of good spanning ability, good overall structural performance, strong seismic capacity, etc., and can well meet the demand of transportation construction. This paper combines the theory of finite element method, finite element software ANSYS and modal analysis theory to establish the finite element model of Rigid-Frame Bridge. And the self-oscillation frequency and vibration characteristics of the model are analyzed as a way to understand the vibration characteristics of Rigid-Frame Bridge. On the basis of the finite element model of Rigid-Frame Bridge, the response characteristics of Rigid-Frame Bridge under the action of seismic waves are analyzed through the action of natural seismic waves at different angles to provide data support for the optimization of its vibration damping design. The first-order transverse self-oscillating frequency of the whole bridge obtained by the simulation of ANSYS software is 0.581Hz, and Rigid-Frame Bridge is mainly symmetrically curved with the middle span and side spans from the fifth order, which is in line with the principle of symmetrical construction of Rigid-Frame Bridges. The maximum value of transverse displacement under transverse seismic wave can reach 92.73mm, and the bridge overturning is more serious, while the effect of transverse seismic wave is smaller. Combined with the vibration characteristics and seismic response characteristics of Rigid-Frame Bridge, the optimization scheme of seismic design is proposed from the two dimensions of main girder and abutment, aiming to improve the service life and safety of Rigid-Frame Bridge.
