Author Identifier (ORCID)
Zhenjiang You: https://orcid.org/0000-0002-4843-2107
Abstract
The growing global demand for mineral resources necessitates deeper excavation, where increasing in situ stresses pose significant geomechanical challenges. Consequently, an accurate strength assessment of deep-seated rock masses is crucial for ensuring the safety and reliability of underground excavations. The Hoek-Brown (H-B) strength criterion remains a widely applied rock strength criterion. However, its conventional form struggles to characterize the full nonlinear evolution of rock strength from pre-critical to critical conditions across varying confining stresses. To address this limitation, this study proposes a Confinement-dependent Transient mi Model (CTM) as an enhancement to the H-B criterion. By incorporating confinement-sensitive variations of mi, calibrated using low-confinement triaxial test data, the enhanced H-B criterion effectively describes the complete nonlinear strength response. Its predictive accuracy is validated against the classical H-B model using 160 triaxial compression tests spanning 14 rock types. The results demonstrate that the enhanced criterion significantly improves the agreement between experimental and theoretical strength predictions. Additionally, the study provides a mechanistic interpretation of the transient mi parameter under varying confining pressures, establishing its role as a brittleness index—where higher mi values indicate greater brittleness, and lower values reflect enhanced ductility under differential stress conditions.
Document Type
Journal Article
Date of Publication
12-1-2025
Volume
182
Publication Title
Engineering Failure Analysis
Publisher
Elsevier
School
Centre for Sustainable Energy and Resources
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Comments
Li, H., Pel, L., You, Z., & Smeulders, D. (2025). Confinement-dependent transient mi for the Hoek-Brown (HB) strength criterion. Engineering Failure Analysis, 182, 110109. https://doi.org/10.1016/j.engfailanal.2025.110109