Characterization of the Venice lagoon silts from in-situ tests and the performance of a test embankment. Keynote Lecture

To protect the historic city of Venice against recurrent flooding, a huge project has been undertaken, involving the design and construction of movable gates located at the three lagoon inlets for controlling tidal flow. The selection of the movable gate foundations demands very extensive and low cost geotechnical characterization of the Venice lagoon soils. These are composed of a predominantly silty fraction combined with clay and/or sand forming an erratic interbedding of various types of sediments, whose basic mineralogical characteristics vary narrowly. To this end two typical test sites in the lagoon area - the Malamocco Test Site and the Treporti Test Site – were selected for the mechanical characterization of Venice soils and a site-specific calibration of the most widely used geotechnical investigation tools. The main outcome of the research carried out at the Malamocco Test Site and some preliminary results from the Treporti Test Site are here presented and discussed.