Seismic cone penetration test (SCPTu)

SCPTu seismic cone is one of the newest multi-measurement tools for the field investigation.
It consists of two parts: the first one is responsible for the measurement of the parameters obtained in the standard CPTu test (the ability to determine the qc, fs, u2 parameters) and the second one for the registration of the shear and vertical wave propagation velocity (which allows to determine the parameters characterizing elastic properties of the soil medium). This test is made sectionally - usually at intervals of 0.5 ÷ 1.0 meters.

Using a special anvil located on the ground surface the seismic wave is raised and registered by the geophone placed in the test apparatus. On the basis of the time differences in the registration of the waves (using accelerometers placed in three dimensions X, Y, Z) the speed of propagation of transverse and longitudinal wave in the medium is calculated (on the distance between the depths corresponding to the following measuring cycles). The shear modulus G₀ is determined in further transformations.