Joint shear strength (Barton–Bandis) calculator

Inputs in the worked example

The live calculator starts with these values; change any of them and every result, check and diagram updates instantly.

Worked example — results

• ✓ Equivalent angle below 70°

Method, formulas and assumptions

• Roughness term JRC log(JCS/σn) = 8*LOG10(60/0.5) = 16.633 °
• Equivalent friction (≤ 70°) = MIN(70,28+16.633) = 44.633 °
• τ peak = 0.5*TAN(RADIANS(44.633)) = 0.49364 MPa

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