On the interpretation of piezocone tests in natural silt and sand mixtures

This paper presents the results of a number of variable rate piezocone tests (CPTU) carried out in the context of three independent site investigation campaigns on intermediate soil deposits. Attention is focused on the analysis of CPTU measurements in relation to the different penetration rates so as to identify drainage conditions during standard tests. Indeed, intermediate soils, typically including a large variety of mixed soil types, are generally characterized by permeability values within the range in which partial drainage is likely to occur during cone penetration and a non-identification of this effect may result in invalid CPTU-based estimates of soil parameters.