Walker, D, Banff, C & Venter, J 2025, 'Strength estimation using an ultrasonic pulse velocity tester', in JJ Potter & J Wesseloo (eds), SSIM 2025: Fourth International Slope Stability in Mining Conference, Australian Centre for Geomechanics, Perth, https://doi.org/10.36487/ACG_repo/2535_47
(https://papers.acg.uwa.edu.au/p/2535_47_Walker/)
Abstract: Uniaxial compressive strength (UCS) is one of the basic and important descriptors for rock mechanics and rock mass strength determination. Field estimated strength (FES) – using International Society for Rock Mechanics and Rock Engineering published methodologies – and field testing are commonly used in conjunction with laboratorytested UCS values for geotechnical design. Commonly used field testing techniques include point load testing and Leeb/Equotip testing. In support of field testing techniques, a number of existing publications deal with the correlation between rock strength and sonic velocity, measured as part of downhole geophysics surveys or from laboratory testing.
To add to this knowledge base, this paper demonstrates the application of sonic velocity measurements using a handheld ultrasonic pulse velocity (UPV) tester. UPV testing is an acoustic non-destructive test method most often used to evaluate the relative quality of rock or concrete structures, and to identify the presence of internal flaws such as cracks or voids.
For this paper, the UPV tester has been used to measure the sonic velocity on drill core to assist with rock strength estimation. Four case studies are given showing the correlation between the measured sonic velocity, FES and laboratory strength testing at the 4 sites. Because this is a relatively new application, the limitations found are presented, as well as suggested workflows and future applications.

Keywords: rock strength, ultrasonic pulse velocity tester, field testing