Dynamic characteristics and seismic response analysis of an asymmetric high-pier long-span continuous rigid-frame bridge

To explore the seismic response behavior of long-span continuous rigid-frame bridges, this study selects an asymmetric high-pier long-span continuous rigid-frame bridge as the subject. A finite element model is developed, and a thorough examination is conducted on both the dynamic performance and seismic response patterns of the bridge. The main findings are as follows: The fundamental frequency is determined as 0.167 Hz, corresponding to a natural period of 5.975 s, which is lower than that of ordinary continuous rigid-frame bridges, thus confirming that high-pier bridges tend to behave as more flexible structural systems. Both the dynamic characteristics and seismic responses of the considered asymmetric bridge exhibit clear asymmetry; the internal force responses of main piers 6# and 9#, as well as transition piers 4# and 12#, differ remarkably under seismic excitations, a fact that deserves particular attention in seismic design. The outcomes of this research are expected to provide a useful reference for the seismic design of similar bridge structures.