Are seismic fragility curves fragile?

A hypothetical seismic site is constructed for which the probability law of the seismic ground acceleration process X(t) is specified. Since the seismic hazard is known, the performance of the incremental dynamic analysis(IDA) and multiple stripe analysis(MSA) based fragilities, which are used extensively in Earthquake Engineering, can be assessed without ambiguity. It is shown that the IDAand MSA-based fragilities are unsatisfactory for moderate and large seismic events, are sensitive to the particular parameters used for their construction, and may or may not improve with the sample size. Also, the usefulness of the optimization algorithms for selecting ground motions records is questionable.

Automated summary

The study shows that fragilities based on IDA and MSA are unsatisfactory for moderate and large seismic events, are sensitive to parameters used, and may or may not improve with sample size. Additionally, the usefulness of optimization algorithms for selecting ground motion records is questionable.