Rock Engineering
Hoek-Brown Rock Mass Strength Criterion
Generalized Hoek-Brown failure criterion (2002/2019) with equivalent Mohr-Coulomb parameters (c', φ'), deformation modulus (Erm), tensile strength, and live non-linear failure envelopes.
Hoek-Brown Rock Mass Strength Criterion
Generalized Hoek-Brown failure criterion (2002/2019) with equivalent Mohr-Coulomb parameters (c', φ'), deformation modulus (Erm), tensile strength, and live non-linear failure envelopes.
Inputs
1. Rock Mass & Intact Properties
2. Application & Confinement (s'3,max)
Theory and formulae
Theory & Formulae (Hoek-Brown 2002/2019)
About this calculator
This free hoek-brown criterion calculator runs entirely in your browser: what you enter is never uploaded. Use the calculation steps and the theory section to check the working, and print a calculation sheet with the inputs, results and formulae for your records.
Methods and references: Hoek et al. (2002, 2019), ISRM.
Topics: hoek-brown, rock mass, gsi, rock mechanics, mohr-coulomb, cohesion, friction angle, rock strength, failure envelope, deformation modulus.
Engineering notice: Results are for preliminary estimation, screening and education. All inputs and outputs must be independently verified by a qualified professional engineer before use in any design or construction decision. Read the full disclaimer
Disclaimer
This calculation sheet was generated with Geotechnical Toolbox for preliminary estimation, screening, educational and verification purposes only. Geotechnical engineering involves site-specific ground conditions and uncertainty. All inputs, methods, results and figures must be independently checked and approved by a qualified Professional Engineer (P.Eng. / PE) before being relied on for design, construction or any safety-critical decision. Results reflect the values entered at the time of printing. The author and site accept no liability for errors, omissions or damages arising from their use.
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