Interpretation of piezocone tests in Venetian silty soils and the issue of partial drainage

The paper reports results of an extensive piezocone testing campaign performed at the Treporti Test Site (Venice, Italy) within a long-lasting research project aimed at developing a reliable geotechnical model of the heterogeneous and highly stratified Venetian lagoon subsoil. The analysis and the interpretation of the large amount of piezocone data in terms of compressibility and consolidation properties of the Venetian silty sediments reveal limitations of standard approaches for the characterization of such intermediate soils. Potentially dilative behaviour as well as partial drainage effects during cone penetration in silts must be taken in careful consideration in order to derive reliable soil parameters from in-situ measurements. According to recently proposed procedures, a preliminary attempt to assess drainage degree during piezocone tests is finally proposed.