Primary and secondary compression characteristics of silts from CPTU: lessons learnt from the Venetian Lagoon sediments.

This paper explores the capability of cone penetration (CPT/CPTU) as an effective tool to estimate primary and secondary compression coefficients in silts, silt mixtures and sand mixtures. The study uses, as a reference database, part of the large amount of CPTU data and subsoil deformation measurements assembled over the last years at the Treporti Test Site (Venice, Italy), within an extensive research project aimed at thoroughly analyzing the stress-strain-time response of the complex assortment of sandy and silty sediments forming the Venetian lagoon subsoil. The development of CPTU-based empirical correlations, providing reliable estimate of the compressibility characteristics of such intermediate soils, may be very useful for geotechnical practice in the Venetian lagoon area or similar depositional environments, since undisturbed sampling of these sediments is very difficult to achieve and geotechnical characterization of this deposits must essentially rely on in situ testing.