Abstract—The mechanical properties of the isolation bearings have a significant effect on the damage probability of the isolated bridges. In this paper a RC seismic isolated continuous highway bridge is selected, and a 3D finite element model is established by OpenSees software. In order to investigate the isolation bearing mechanical parameters on the effect of bridge seismic fragility, the seismic fragility functions of bridge components under certain limit state and different isolation bearing parameters were obtained. The multi-objective functions of the series bridge system and weighted bridge system are found based on the seismic fragility of bridge components and are solved by the Multi-Objective Genetic Algorithm (MOGA). The results showed that the selection of isolation bearing parameters has a great influence on the seismic fragility of the whole bridge. The optimum isolation bearing parameters for the series system and weighting system can both improve the bridge seismic fragility. However, the isolation bearing parameters from the bridge series system model improve seismic performance more effectively.
 

Cite: X. H. Long, J. Fan, F. F. Nie, and Y. T. Zhang, "Seismic Fragility Based Optimum Design of LRB for Isolated Continuous Girder Bridge," International Journal of Structural and Civil Engineering Research, Vol. 4, No. 3, pp. 231-236, August 2015. doi: 10.18178/ijscer.4.3.231-236