Barton-Bandis Criterion
Inputs and outputs for nonlinear joint/discontinuity shear strength.
τ = σn tan(φr + JRC log10(JCS/σn))
Barton-Bandis is intended for rock joint or discontinuity shear strength. JLab evaluates it only while 0 < sigma_n <= JCS and the apparent friction angle is between 0 and 70 degrees. Principal calibration is disabled for this criterion.
| Input | Units / Range | Description |
|---|---|---|
| Residual Friction Angle | Degrees; 0 to 70 | Residual friction angle of the discontinuity surface. |
| JRC | 0 to 20 | Joint roughness coefficient. |
| JCS | Stress; min 0.001 MPa equivalent | Joint wall compressive strength. |
Available Outputs
- Normal/shear curve and derived principal-stress curve.
- Barton-Bandis input parameters in the Results panel.
- Selected Sigma3 or SigmaN range maximum and corresponding shear strength.