Applicability of Artificial Waves to Seismic Vulnerability of High-Speed Railway Continuous Bridge

Artificial seismic waves can be easily generated by software, and needs identification if they can be used to evaluate the seismic vulnerability of general bridges. A finite element model of a (48+80+48)m continuous girder bridge in a high-speed railway was built by OpenSEES software, and was calculated by an incremental dynamic analysis (IDA) using both the artificial waves and actual waves. The seismic fragility curves for major structural components under the artificial waves and actual waves were developed assuming lognormal distributions for both the demand and capacity of bridge structure, and then compared with each other. The comparison results show that there is a perfect consistency between the seismic responses under both the artificial waves and actual waves for most components. Although the seismic responses of sliding layer under the actual waves are slightly different from those under the artificial waves, the largest error of damage exceeding probability between them is still acceptable. Therefore, the artificial waves can be used to evaluate the seismic vulnerability for the continuous girder bridges in a high-speed railway under earthquakes.