**5. Conclusions**

In this paper, usinga curved bridge with double-column piers as an engineering example, weestablished a three-dimensional finite element solid unit model of acurved bridge. The collision response analysis of the curved bridge was performedthrough a nonlinear dynamic time history analysis. According to the response characteristics of the curved bridge, the damping device and unseating restrainer were used for the combination optimization to analyze the seismic mitigation and unseating prevention of the curved bridge. The analysis led to the following conclusions:

(1) During earthquakes, the bending–torsion coupling phenomenon inthe girders of curved continuous girder bridges is serious, and the displacement magnitude and direction of the inside and outside of the contact surface of the expansion joints of each bridge span are inconsistent, which can easily cause uneven local collisions at the contact surfaces. The high contact stress causes local compressive and tensile damage to reinforced concrete. At the same time, the increase in the relative radial and tangential displacement caused by the torsion of the girder could lead to the unseating of the girder.


**Author Contributions:** Data curation and methodology, Z.L.; Formal analysis, C.Y.; Writing—review & editing, S.K. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by the Chongqing Natural Science Foundation of China (cstc2018j cyjAX0001).

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Some data, or models used during the study are available from the corresponding author by request.

**Conflicts of Interest:** The authors declare no conflict of interest.
