S-CPTU tests

TGAS-08 S-CPTu - Pagani

Using a piezocone (electric probe) has significantly improved the data obtained in static testing both in terms of measurement precision and data sampling frequency.
Pagani piezocones indeed allow the acquisition, during the continuous driving movement, of the qc (tip resistance) and fs (sleeve friction) values at each centimetre of depth compared to the 20 centimetres which can be obtained with Begemann type mechanical bits.

The system also acquires the seismic waves, the U value (hydrostatic pore pressure), the angle of the set of rods and the dissipation time (time measured between measurement of the overpressure obtained during the driving stage and the pressure measured when releasing the driving pressure).

TGAS08 system

Electrical connections and components:

  • TGAS08 – The acquisition system.
  • DIGITAL SEISMIC PROBE – Acquires seismic waves.
  • ENCODER – Measures the depth and speed of insertion.
  • POWER SUPPLY – The system is powered electrically by the penetrometer battery, via a standard socket.
  • ROD ADAPTER – Mechanically connects the piezocone to the thrust rods.
  • GPS-GPRS ANTENNA – Allows the GPS coordinates to be acquired and sending of the tests via the GSM network.
  • CPTU-ACQ SOFTWARE – Installed on a notebook, it allows tests to be imported from the TGAS08 system.

Piezocone specifications

Measurement channels: Dimensions:
Tip resistance (qc): 50; 100 MPa Cone apex angle: 60°
Sleeve friction (fs): 1,6 MPa (titanium) Diameter: 36 mm
Pore pressure (U): 2,5 MPa Section area: 10 cm²
Tilt: 0 – 20° Friction sleeve surface: 150 cm²
Tip area factor (a): 0,80 Weight: 2,1 kg
Sleeve area factor (b): 0 Length: 413 mm

 

Seismic probe specifications

Sensor type: Triaxial accelerometer
Number of sensors: 2
Distance between sensors: 0,5 metres
Sampling frequency: 30000 samples per second

 

CPTU-ACQ software

The TGAS08 system includes the CPTU-ACQ Software. Key functions:

  • Real-time display of acquired and calculated data (Qc, Qt, Fs, Rf, U2, U2/Qc, Qc-U2, U2-U0, Speed, Tilt, Distance).
  • Management of dissipation tests.
  • Printing of all graphs, with customisation of print formats.
  • Management of tests archive.
  • Exporting tests as ASCII, EXCEL, PDF and DXF files.

Penetrometers