Features

  • Integrated design compatible with standard Becker drill system and 6 5/8” drill string pipe
  • Mobile trailer for access around project sites including dam crests and benches
  • Redundant sensor measurements for continuous operation

Advantages

  • Direct measurements of force and acceleration at bit and top of drill string
  • Monitoring of drill string displacement and hammer blows during driving
  • Capable of sounding depths greater than 60 m

Applications

The basic BPT is limited due to variable and inconsistent hammer energy, along with significant frictional losses along the length of the deployment rods. By including downhole energy measurements, the actual driving energy being delivered to the iBPT bit is computed from direct measurements. The delivered energy to the penetrating tip is used to energy-correct the BPT blowcounts and determine equivalent SPT N60 values.

The iBPT test is an essential tool to accurately and properly characterize:

  • gravel and cobble deposits
  • rock-fill dams
  • challenging glacial soils
  • mixed and layered deposits
  • water dams

Information Provided

  • Dynamic driving measurements at bit and top of drill string
  • Energy normalized penetration resistance, NB30 values
  • Equivalent SPT N60 values to estimate soil properties and evaluate liquefaction susceptibility
  • Continuous profile of penetration resistance to assist in stratigraphic interpretation

References

Dejong et al., 2017, "Instrumented Becker Penetration Test 1: Equipment, Operation, and Performance" ASCE Journal of Geotechnical and Geoenvironmental Engineering, DOI: 10.1061/(ASCE)GT.1943-5606.0001717.

Ghafghazi et al., 2017, "Instrumented Becker Penetration Test 2: iBPT-SPT Correlation for Characterization and Liquefaction Assessment of Gravelly Soils, ASCE Journal of Geotechnical and Geoenvironmental Engineering, DOI: 10.1061/(ASCE)GT.1943-5606.0001718