Study on Simplification Conditions of Curved Regular Bridges under Seismic Effect

A radius of curvature 20 times greater than the deck width of the bridge (R≥20b) is required as a specification in the regular bridge simplification conditions of the seismic response of curved girder bridges. Selecting benchmark bridges and employing parameter analysis method, this article studies on the effect of R/B value of the curved girder bridge on the response ratio of the seismic response calculated using the finite element model and that using a regular girder bridge. This study shows that on conditions that the deck width of the bridge is constant, the smaller the radius of curvature and the larger the B/R value (i.e., the smaller the R/B value) of the curved girder bridge are, the greater the difference between the seismic response of the curved girder bridge and the result calculated with a regular girder bridge is, and the difference is more significant under traverse seismic effect than that of longitudinal seismic effect. On conditions that the radius of curvature is constant, the impact of the change of B/R value due to the deck width change of the bridge on the difference between the seismic response of the curved girder bridge and the result calculated with a regular girder bridge is insignificant. Compared with the deck width of the bridge, the difference between the seismic response of the curved girder bridge and the result calculated with a regular girder bridge is more sensitive to the radius of curvature.