GNGTS 2019 - Atti del 38° Convegno Nazionale

420 GNGTS 2019 S essione 2.2 The implementation in IRMA of the UniGE vulnerability model has produced plausible results, both in terms of damage scenarios and total risk at national scale. The number of victims per year in masonry buildings, at national scale, is 78, to be compared with about 5000 in the last 50 years (from Belice earthquake in 1968), including victims in reinforced concrete buildings. The simulated scenario of L’Aquila earthquake (2009), for masonry buildings only, gives 79 victims in L’Aquila (95 in the whole area), which is compatible for the actual data (309 victims, around 1/3 in masonry buildings); also, the estimation of repair/reconstruction costs in L’Aquila is very good, being between 329 and 486 M€ (depending on the assumed cost function), in comparison with the actual cost of 480 M€. Moreover, 217 collapsed buildings and 47.5% of unusable buildings have been estimated in L’Aquila. Consequences in Rome are negligible, despite the PGA of the INGV shake map is probably a bit overestimated. References Bernardini A., Lagomarsino S. Mannella A., Martinelli A., Milano L., Parodi S. (2010) Forecasting seismic damage scenarios of residential buildings from rough inventories: a case-study in the Abruzzo Region (Italy). Proc. IMech E Part O: J. Risk and Reliability , 224: 279-296. Lagomarsino S., Giovinazzi S. (2006) Macroseismic and mechanical models for the vulnerability and damage assessment of current buildings. Bull Earthquake Eng , 4(4): 415-443. Margottini C., Molin D., Narcisi B., Serva L. (1992) Intensity versus ground motion: a new approach using Italian data. Engineering Geology , 33: 45-48. ASSESSMENT OF SITE EFFECTS IN VOLCANIC AREAS: RESULTS FROM SEISMIC MICROZONATION STUDIES IN THE ISLAND OF ISCHIA (NAPLES, ITALY) M. Mancini 1 , I. Gaudiosi 1 , M.C. Caciolli 1 , G. Cavuoto 2 , V. Di Fiore 2 , G. Milana 3 , M. Vassallo 4 , F. Silvestri 5 , A. D’Onofrio 5 , G.A. Allenza 5 , P. Pompa 5 , M. Coltella 1 , G. Cosentino 6 , A. Pietrosante 1 , E. Tarquini 1 1 Istituto di Geologia Ambientale e Geoingegneria, CNR, Roma, Italy 2 Istituto di Scienze Marine, CNR, Napoli, Italy 3 Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Roma1, Roma, Italy 4 Istituto nazionale di Geofisica e Vulcanologia, Sezione di Roma1, L’Aquila, Italy 5 DICEA, Dipartimento di Ingegneria Civile, Edile ed Ambientale, Università degli Studi di Napoli Federico II, Napoli, Italy 6 Istituto Geoscienze e Georisorse, CNR, Pisa, Italy Introduction. The Seismic Microzonation (SM) of Level 3 allows quantifying numerically seismic amplification effects on microzones, previously introduced after detailed geological reconstructions of local subsoil and geophysical-geotechnical characterization of bedrock and cover terrains. Major goals of the Level 3 SM studies are, indeed, the calculation and mapping of Amplification Factors (AF) at ground for different period intervals of engineering interest, and the defining of acceleration response spectra for each microzone. According to the Italian standards (Gruppo di Lavoro MS, 2008; SM Working Group, 2015), this can be achieved through 1D and 2D numerical simulations of the ground motion performed respectively on stratigraphic logs and on engineering-geological cross sections, with litothypes parametrized in terms of Vs and G/G 0 -γ and D-γ curves. The obtained results are basic for correct Urban Planning Strategies and Seismic Risk Mitigation Policies. It is here presented the case of Level 3 SM studies concerning the municipalities of Casamicciola Terme, Lacco Ameno and Forio (Island of Ischia, Naples, Italy), affected by the 21 August 2017 earthquake (Mw 3.9, http://iside.rm.ingv.it/en/event/16796811 ), which caused two victims and heavy damages to a large number of buildings. Ground acceleration was 0.28g at IV.IOCA station, EW component.