The technical note, starting on page 171 of the February 2018 issue, provides information on a proposed calibration routine for a GDS Hardin-type resonant column. In contrast, the GDS Stoke type resonant column has a much more industry wide agreed calibration procedure, principally due to the fact that it is a true fixed-free configuration.
The Hardin-type calibration procedure is more complex due to the inherent partial fixed configuration of the drive system which is required to allows anisotropic resonance to occur. Thank you to H. Li, H. He and K. Senetakis for publishing their extremely interesting and informative work.
“Calibration exercise of a Hardin-type resonant column”, Li, H. et al. (2018). Géotechnique 68, No. 2, 171-176.
Featured Product Information:
Hardin Type Resonant Column Apparatus (H-RCA) is a system that allows samples to be tested in resonance while maintaining an anisotropic loading up to 2kN. This is achieved by a slender, thin walled loading column passing through the drive system to the topcap. The GDS Hardin Oscillator contains an electro-magnetic drive system incorporating precision wound coils and composite sintered neodymium iron boron (NdFeB) “rare-earth” magnets.
The GDS Hardin Oscillator can be mounted in a standalone system with an integral axial force actuator (shown opposite) for post resonance testing up to 5kN. Or as a cell for integration into a standard loadframe up to 50kN