응답면 기법을 이용한 교량 지진손상의 빠른 평가

초록

Seismic risk analysis is generally performed for a group of structures, where a single set of fragility curves is developed to represent the seismic performance level of the group. While this approach could be applied for estimation of the average seismic risk of a large group of structures, seismic fragility of an individual structure should not be same as the seismic fragility of the structural class. Development of fragility curves of an individual structure, however, requires a probabilistic seismic damage assessment where a large number of time-history analysis must be accompanied. This study proposes a new approach for rapid assessment of probabilistic seismic damage of structures based on the response surface method. The structural configuration- related parameters, such as number of spans, span length, and/or pier height, are considered as the input variables for the response surface model, which could estimate the seismic damage of track-on-steel-plate-girder railway bridges without having to run a large number of structural analyses. A comparison has proved that the developed response surface model is consistent with the structural analysis-based damage assessment with high degree of accuracy.