SCPTU SOUNDING

We implement orders for SCPTU soundings. This method provides detailed in-situ information on soil parameters. Seismic tests can be conducted along the course of CPT or CPTU (SCPT or SCPTU respectively) investigations. It is a convenient and effective tool to determine shear wave velocity (vp) and pressure wave velocity (vp). These parameters enable determining the initial shear modulus G0, deformation modulus E0 (equivalent to Young’s modulus for soils), which further enable calculating the Poisson’s ratio.

HOW IS A SCPTU TEST CONDUCTED?

SCPTU static sounding involves measuring the time a shear wave propagates in the soil between the ground surface and the probe, which is additionally fitted with accelerometers or geophones. A seismic wave is generated by hitting (in the horizontal direction – a transverse, shear wave) a steel element placed in the soil, on the ground surface. Upon impact, measuring of the signal starts (velocities or accelerations) at the probe tip. Based on the time it takes a seismic wave to reach a specific depth that the probe is currently at, the mean soil propagation velocity for a shear wave is determined. By conducting the tests every, e.g., 1 m of depth and comparing the measurement results for adjacent levels, it is possible to determine wave propagation velocity at a given stratum with 1 m resolution along depth.
Seismic tests are conducted along the course of CPT or CPTU (SCPT or SCPTU) tests. SCPTU soundings involve measuring the time a shear wave propagates in the soil between the ground surface and the probe tip, which is additionally fitted with accelerometers. A seismic wave is generated by hitting (in the horizontal direction – a transverse, shear wave) a steel element placed in the soil, on the ground surface. Upon impact, measuring of the signal starts (velocities or accelerations) at the probe tip. Based on the time it takes a seismic wave to reach a specific depth that the probe is currently at, the mean soil propagation velocity for a shear wave is determined. By conducting the tests every, e.g., 1 m of depth and comparing the measurement results for adjacent levels, it is possible to determine wave propagation velocity at a given stratum with 1 m resolution along depth.

Measuring elements of a seismic system can be permanently built into a CPTU cone or can be added as a separate conduit section. Such a system can be equipped with a single accelerometer positioned in the horizontal plane (in one direction) or a set of three accelerometers. This enables measuring regardless of the excitation direction in the horizontal plane. Furthermore, seismic tests enable measuring shear wave velocity (Vp) and determining a deformation modulus (E0) and a Poisson’s ratio (v).
We also deal with measuring the electrical conductivity of the soil. This test is conducted using the CCPTU method.