Laura Tonni

Site characterization of intermediate soils (silts and silty sands) through piezocone tests. Research is based on a number of field studies carried out in intermediate deposits, including the Venetian Lagoon subsoil and other relevant deposits of the Po river valley. The study aims at developping reliable interpretation procedures of piezocone measurements in such soils, where standard and well-accepted empirical correlations seem to fail in providing good estimates of their mechanical parameters due to partial drainage phenomena around the advancing cone. Recent developments in this field have dealt with the estimate of liquefaction susceptibility of silty sands, based on the in-situ testing campaigns carried out in the Po river plain deposits within the research projects "Studio Teorico e sperimentale per la valutazione della suscettibilità alla liquefazione dei depositi sabbiosi: effetto delle condizioni stratigrafiche, dell'ambiente deposizionale e delle caratteristiche dell'azione sismica sull'innesco del fenomeno" (Bando ALMAIDEA 2017) e "Tecnologie innovative per la riduzione del rischio sismico delle costruzioni" (Bando POR-FESR 2014-2020, Project no. PG/2015/737636). Within the scope of this research topic, attention has been also focused on the definition of quality standards for the CPTU tests, leading to the design of a tool for verifying the degree of saturation of the piezocone. The proposed system is currently patented in Italy, the Netherlands, and the United States.

In the context of riverbank stability, research activity has also dealt with the analysis of the seismic response of an irrigation canal riverbank (the Canale Diversivo di Burana), which was one of the most severely damaged structures by the seismic sequence that in May 2012 struck a large area of the Emilia-Romagna region, in Northern Italy. The study has been carried out in cooperation with researchers from various Italian Universities and technical experts of the Geological, Seismic and Soil Survey Regional Department. The main objectives of the analysis are: identification of the river bank seismic response during the 2012 earthquake, investigation of the damage causes, recommendation of remedial measures and seismic risk mitigation actions towards possible future earthquakes. To this purpose, a number of geotechnical investigations have been performed (in situ tests, geophysical investigations and laboratory tests) and an accurate geotechnical model for the seismic stability analyses has been thus defined. Potential liquefaction phenomena of the shallow sandy soils, in the foundation subsoil, have been taken into account in the analyses.