Statistical analysis of Hoek-Brown shear strength properties for single and multiple intact rock units
Year: 2026
Type: article
Abstract: In the practice of geotechnical mining, the shear strength of intact rock is typically characterized using the Hoek-Brown failure criterion. The presence of veinlets, micro-defects and/or a stockwork texture of tested rock specimens, a common feature of mineralized rock, leads to variability of results from strength testing, resulting in the need to carry out regression analysis of the test results to find a best fit Hoek-Brown failure curve. This paper presents a way of accounting uniaxial compression tests separately from triaxial tests, so to decrease the biasing towards one type of testing in particular. This alternative form of doing the regression analysis may be applicable when the quality of uniaxial compression tests is known to be of similar good quality as triaxial tests, as could be the case in some mining projects. In the proposed methodology, a measure of the quality of the fit of the Hoek-Brown failure curve is obtained by computation and interpretation of a correlation factor. For cases in which several intact rock units are being characterized, a global correlation factor for all geotechnical units considered together is proposed. To further quantify the variability of results obtained from laboratory testing, a probability analysis of the Hoek-Brown properties is also presented.
Source: Soils and Rocks
Institution: University of Minnesota, Duluth
Language: English
Topic: Rock Mechanics and Modeling
Subfield: Mechanics of Materials
Field: Engineering
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W7222409024