Fragility Analysis of Large-Span Continuous Rigid Bridge Considering Wave Passage Effectt

To study wave passage effect on the fragility of the large-span continuous rigid bridge (LSCRB) in mountainous area, an actual LSCRB in southwest area was chosen as the study object. Twenty earthquake records were selected using the spectra-compatible method. Then, incremental dynamic analysis (IDA) of the bridge structure was conducted under uniform excitations and non-uniform excitations to obtain the fragility curves. The analysis results show that the relative displacements of the piers increase with the height of piers, and the relative displacement of the highest pier is around 1.03-2.81 times that of low pier, but the seismic design of low piers should be paid more attention because the damage probability of low piers is greater than that of high piers. Compared with the case under uniform excitations, the wave passage effect may reduce the probabilities of slight and moderate damages of low piers, and increase those of high piers. Furthermore the probability of extensive damage may be increased by the wave passage effect both for the low and high piers. As a result, in the seismic design of the high-pier bridges, it is necessary to consider the effect of wave passage on bridge structure, especially for the high-intensity zones.