Helical probe tests in residual soils of the Appalachian Piedmont

ABSTRACT

Helical probe tests (HPT) are a quick and economical means for manual field testing of soils to depths of 1.5 m with readings taken at 0.15-m intervals in only 10 min. The equipment is lightweight (only 2 kg) and thus amenable to deploy on initial site reconnaissance explorations, shallow pavement projects, earth retention walls, and/or compaction of fills. Although suitable for use in a variety of geomaterials: sands, silts, clays, and mixed soils, the specific application to residual fine sandy silts and silty fine sands of the Appalachian Piedmont and Blue Ridge geologic provinces is shown here. Existing relationships for converting the measured HPT torque reading to equivalent cone penetration testing (CPT) tip resistances are reviewed, as well as other trends.

KEYWORDS:

• In-Situ testing
• manual tests
• probes
• soils

Acknowledgments

The authors would like to thank Steve Frank of Apex Design, Suwanee, Georgia for providing the GT team with two HPT probes. We would also like to thank Tyler Wood of Ahlberg Engineering, Marietta, Georgia for providing the Athens field data. We also extend appreciation to ConeTec Investigations of Richmond, BC and Design House Consultancy of New York, NY for their support of in-situ research activities.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Design House Consultancy of New York, NY; ConeTec Investigations of Richmond, BC.