Soil Mechanics & Lab Tests
Mohr-Coulomb / Triaxial Test Analyzer
Determine Mohr-Coulomb effective cohesion (c') and friction angle (φ') from triaxial or direct shear test stages using linear regression, and plot failure envelopes.
Mohr-Coulomb / Triaxial Test Analyzer
Determine Mohr-Coulomb effective cohesion (c') and friction angle (φ') from triaxial or direct shear test stages using linear regression, and plot failure envelopes.
Inputs
Experimental Test Stages
No test stages added.
Results
Enter at least 2 experimental test stages above, or click a Preset at the top to compute Mohr-Coulomb parameters.
Theory and formulae
Mohr-Coulomb Failure Theory
About this calculator
This free mohr-coulomb analyzer 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: ASTM D2850, ASTM D4767, ASTM D3080.
Topics: mohr-coulomb, triaxial test, direct shear, cohesion, friction angle, failure envelope, mohr circle.
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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