Simplified probabilistic seismic performance assessment of masonry buildings with consideration of aleatoric and epistemic uncertainties

A simplified method for estimating seismic risk with consideration of aleatoric and epistemic uncertainties is briefly presented and its application is demonstrated by means of an example of a three-storey masonry building. Epistemic uncertainties due to modelling parameters are considered by utilizing Latin Hypercube Sampling technique. Fragility parameters are estimated for the near collapse limit state by using the N2 method and approximate incremental dynamic analysis of a single-degree-of-freedom system. It is shown that the epistemic uncertainties significantly affect fragility parameters, since they increase dispersions of the seismic response parameters. Although the estimated seismic risk obtained by the two methods is similar, conclusions cannot be generalized since seismic risk may be affected by the choice of accelerograms used and by the type of the structure.