Analisi dei fenomeni deformativi indotti dalla sequenza sismica emiliana del 2012 su un tratto di argine del Canale Diversivo di Burana (FE)

The seismic sequence that in May 2012 struck a large area of the river Po Valley (Emilia-Romagna region, Northern Italy) triggered significant fractures and deformations in a number of riverbanks located close to the earthquake epicenter. Among them, one of the most severely damaged structures turned out to be the banks of an irrigation canal known as Canale Diversivo di Burana, flowing through the small village of Scortichino (Municipality of Bondeno), near the historic town of Ferrara. Large, longitudinally-oriented ground cracks were observed along a 3 km bank stretch, causing in turn severe structural damages to a large part of the approximately one hundred houses and productive activities built on the bank crown. In order to interpret the response of such soil structure during the 2012 earthquake by identifying possible damage causes as well as to suggest relevant remedial measures and seismic risk mitigation actions towards possible future earthquakes, the Emilia-Romagna regional authority launched an in-depth study carried out by a number of research groups from various Italian universities in cooperation with technical experts of the Geological, Seismic and Soil Survey Regional Department. To this purpose, a number of geotechnical investigations were performed (in situ and laboratory tests) and an accurate geotechnical model for the seismic stability analyses was thus defined. Potential liquefaction phenomena of the shallow sandy soils, in the foundation subsoil, were taken into account in the analyses. The paper describes the main features of the extensive study carried out by the working group and summarizes the most significant achievements of the analyses.