Typological Damage Fragility Curves for Unreinforced Masonry Buildings affected by the 2009 L'Aquila, Italy Earthquake

Background: Seismic risk mitigation has become a crucial issue due to the great number of casualties and large economic losses registered after recent earthquakes. In particular, unreinforced masonry constructions built before modern seismic codes, common in Italy other seismic-prone areas, are characterized by vulnerability. order implement policies, analytical tools necessary generate scenario simulations. Methods: Therefore, data collected during inspections 2009 L’Aquila, earthquake used derive novel fragility functions. Compared previous studies, interpreted accounting for presence buildings not inspected those being undamaged. An innovative building damage state is proposed based on response different structural elements recorded survey form: vertical structures, horizontal stairs, roof, partition walls. suggested formulation, combination their performance weighted typical reparation techniques relative size elements, estimated from database complete geometrical surveys developed specifically this study. Moreover, estimates earthquake-related removing preexisting reported inspection form. Results: Lognormal curves, terms grade as function typological classes peak ground acceleration, derived maximizing likelihood merits compared with studies highlighted. Conclusion: The correction account uninspected delivers curves that less “stiff” reach median lower acceleration values. feature influences most quality.