Over the last 50 years, the city of Venice has seen a significant increase in the frequency of flooding with a record tidal level of nearly 2m measured in November of 1966.
Since then, numerous engineering solutions have been proposed to protect Venice from flood waters, including the use of movable gates located at the three Lagoon inlets – the Lido, Malamocco, and Chioggia. For the design of these submersible mobile barriers, an extensive geotechnical study was undertaken to characterize the subsurface conditions. A key element in the prediction of performance for these “heavy” structural elements was the estimation of settlements and behavior of the soft foundation soils under normal operating conditions. Complicating the problem, the soils of the Venice Lagoon are characterized by very erratic depositional patterns resulting in an extremely heterogeneous stratigraphy. The mineralogical composition of these soils, on the other hand, is quite uniform.
This presentation will focus on the methodology used to estimate the consolidation settlements of the highly heterogeneous silty sandy clayey soils, accounting for the variability in the stratigraphic units. The presentation will also showcase a brief description of the project and address some of the implications of future sea-level rise for coastal cities.