GNGTS 2019 - Atti del 38° Convegno Nazionale

616 GNGTS 2019 S essione 3.2 By the use of these surveys is possible to reduce investigation costs in the phase of geological characterization of a landslide area. Staring from the stratigraphy of the underground given by borings, a good geological model through the spectra analyses has been obtained. Moreover, HVSR spectra provide useful information about geomechanical features of the layers. Layers with poor geomechanical proprieties result on a strong impendence contrast above layers with good mechanical coherence; otherwise, horizons related to substrate formation, devoid of significant contrasts, are better identified by a smoothing curve. References Barbero D., Boano P., Forno M.G.; 2014a: Fenomeni di instabilità di versante in un tratto Astigiano della valle del Fiume Tanaro che interessano forme fluviali sospese. In: Atti e contributi del convegno “L’alluvione del 5-6 Novembre 1994 in Piemonte: venti anni di attività nella previsione e prevenzione in ambito gelogico-idraulico”, 28-29 ottobre 2014, Torino, Regione Piemonte, Ordine Reg. Geol. Piemonte, CNR-IRPI, GEAM (Eds), 123-128. Barbero D., Doglione A., Forno M.G., Gattiglio M.; 2014b: The importance of stratigraphic and structural aspects in the mitigations of landslides involving slopes near Aguggia (San Damiano d’Asti), In: Miscellanea INGVAbstract Volume AIQUA Congress 2015: “The Plio-Pleistocene continental record in Italy: highlight on stratigraphy and neotectonics”, 24-26 Febbraio 2015, Torino, Monegato, G., Gianotti, F., Forno, M. G. (Eds), AIQUA, 11-12. Barbero D., Tissoni A.; in press: Geotechnical study of a landslide reactivation in clay soils (central Piedmont, NW Italy). Journal of Geotechnical Engineering. Boni A., Boni, P. Braga G., Bruno G., Casnedi R., Corsi M., Gatto G.O., Gatto P., Mosna S., Motta E., Perotto G., Rampoldi R.; 1969: Foglio 69 “Asti”. Carta Geologica d’Italia alla scala 1:100.000, II ed., Serv. Geol. It., Roma. Carraro F., Valpreda E., 1991. The Middle-Upper Quaternary of the Asti Basin. Il Quaternario It. Journ. Quatern. Sci, 4(1), 151-172. Fig. 3 - Comparison between the experimental (red) and synthetic (in blue) H/V3 curves (above). Black curves denote 95% confidence interval. Velocity-depth model obtained from a passive seismic study next to H/V3 site (below).