Method and equipment to determine, in situ, in a rigorous and repetitive way, the load bearing characteristics or geotechnical parameters of a sandy soil, according to the following phases: circumscribing, in situ, in the sandy soil, a sand sample, having a tubular, cylindrical shape, with a predetermined external diameter, a predetermined internal diameter, and predetermined length; applying to the sample, in correspondence to its internal, cylindrical surface, a radial pressure of predetermined value; and applying to the sample, in correspondence to its upper annular surface, an axial pressure, the value of which is made to increase to a value at which the sample ruptures. The geotechnical parameters are easily deduced from the value of axial pressure which causes the rupture, as well as from the values of the radial pressure and of the internal and external diameters of the sample itself.