GNGTS 2024 - Atti del 42° Convegno Nazionale

Session 2.2 GNGTS 2024 On the reconnaissance of slopes suscepHble to co-seismic failures in Daunia (Apulia, Southern Italy) F. Fredella 1 , V. Del Gaudio 1 , N. VenisH 1 , J. Wasowski 2 1 Dipar9mento di Scienze della Terra e Geoambientali, Università degli Studi di Bari “Aldo Moro”, Bari 2 Consiglio Nazionale delle Ricerche, Is9tuto di Ricerca per la Protezione Idrogeologica, Bari IntroducHon Co-seismic landslides are capable of causing significant damage even to structures and infrastructures that resist the direct effects of earthquake ground shaking. It is therefore important to idenCfy the slopes potenCally exposed to seismic destabilizaCon for hazard miCgaCon and prevenCon. A regional- to local-scale invesCgaCon of sites suscepCble to co- seismic failure requires allocaCon of considerable resources, which should be prioriCzed by focusing abenCon on slopes with greater probability of being mobilized by seismic shaking. Here we explore the potenCal of reconnaissance-type idenCficaCon of slopes suscepCble to co-seismic failures in the Daunia Mountains, at the NW border of the Apulia region. This is done by comparing the resistance demand placed by local seismicity on slope sites and the actual slope resistance. To this end, we take into account i) the basic seismic hazard inferred at regional scale from earthquake records, ii) the local effects of site amplificaCon phenomena and iii) expediCous esCmates of slope resistance to seismic shaking. Our study benefits from the large amount of data acquired in the ongoing seismic microzonaCon (SM) studies of the Apulia region. We focus on the Daunia Mts., which are known for the widespread presence of marginally stable slopes consisCng of clay-rich flysch materials and rainfall-triggered landsliding (e.g., Wasowski et al. 2010). Although Daunia is exposed to earthquakes generated in the surrounding areas, lible is known about the suscepCbility of its slopes to seismic failure. Basic slope resistance demand A first stage for the idenCficaCon of slopes subject to seismically induced landslides consists in defining the resistance demand placed on slope by the regional seismicity. For this purpose, the starCng point is the assessment of the basic seismic hazard, represented as a probabilisCc