Cone Penetration Test CPT
In order to determine, in addition to the lift, also the inherent strength characteristics of the materials constituting the foundation soils, one can operate with the cone penetration test. CPT test consists in a rod attachment into the ground in a pre-drilling hole with piling speed of about 20 mm / s. The rod is protected by a sleeve, with a conical tip.
The cone penetration test allows acquiring the tip resistance value to the infixion and the side friction value, variating with the changing lithostratigraphic and geotechnical properties of the soil.
The parameters values are then correlated by empirical correlations (De Beer and Martens, Schmertmann), allowing an estimate of the technical soil properties and the definition of a stratigraphic profile of the soil.
Dynamic cone Penetration Test (DCPT)
DCPT consists in a vertical inflicting percussion into the ground by a conical metal tip placed at the end of a steel rod, extendable by adding further rods. The following step is recording the number of strokes necessary to obtain a prefixed advancement.
The information provided by dynamic penetration test are continuous, because the penetration resistance measurements are performed throughout the piling.
The field of use is very large because the test can be performed on all types of soil, even if it is mostly used on coarse-grained soils.
The test provides a qualitative assessment of the densification degree and of the soil consistency.
