PSI - Issue 44

Angela Chiecchio et al. / Procedia Structural Integrity 44 (2023) 11–18 Angela Chiecchio/ Structural Integrity Procedia 00 (2022) 000–000

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The BMSE scenarios identified for the three reference sites of Firenze, L’Aquila and Catania are shown in Fig. 2 , Fig. 3 and Fig. 4 Same as Fig. 2, for the site of Catania. 4, respectively. In these figures, the circles show the resulting scenario epicentral distances ( R epi ), in colour where they intersect the respective source. The fitting between the target 475 years UHS (grey lines) and the Ambraseys et al. (1996) prediction (dashed coloured lines) is also shown, together with the M w - R epi values that identify the scenario at play, with the corresponding error index ( err ). Light grey points show the historical epicentres with M w ≥ 5.5, from CPTI15 (Rovida et al., 2022). Note that, for the site of Catania, the scenario from the volcanic source zone ZS936 has been added to the selection, because of the relevance of macro seismic observations from volcanic earthquakes, for the site, despite its associated error index is higher than the chosen threshold of 0.3.

Fig. 2 Best matching scenarios for the site of Firenze: blue line spectrum refers to the ( M w - R epi ) scenario obtained for the ZS915 source, while the red line spectrum refers to the ( M w - R epi ) scenario corresponding to ZS916 source. Grey spectra are the MPS04 UHS for 475 years. Light grey points show the epicentres of historical earthquakes with M w ≥ 5.5 from CPTI15 (Rovida et al., 2022).