Geology Joint Shear Strength Barton Bandis Calculator
Ideal joint peak shear τ=σn tan[JRC log10(JCS/σn)+φr], same stress units. Actual scale/weathering/normal stress applicability and JRC/JCSindependent; valid angle0–<90°, not residual shear or structural safety.
Description
Barton–Bandis joint shear estimates use roughness, compressive strength and effective normal stress.
Barton–Bandis joint shear estimates use roughness, compressive strength and effective normal stress.1
The empirical branch and friction-angle convention constrain the calculation. Use this tool to calculate the stated observation or conditional model from supplied measurements.
When to use Geology Joint Shear Strength Barton Bandis Calculator
Use this tool to calculate the stated observation or conditional model from supplied measurements. Establish the sample and coordinate basis, matching units, calibration source and applicable model assumptions.
How to use Geology Joint Shear Strength Barton Bandis Calculator and understand its results
- Establish the sample and coordinate basis, matching units, calibration source and applicable model assumptions.
- Enter actualEffectiveNormalStress, callerMatchedJointCompressiveStrength, callerIndependentlyAssessedJrc, callerMatchedResidualFrictionAngleDegrees, using the field meanings and rules below, then run the tool.
- Read result.conditionalBartonBandisPeakShearStress. Interpret each field using the units, signs and evidence rules below.
- If input validation fails, correct the reported field and run again. Before applying a successful result, check the stated reference scope, units, assumptions and any retained unknown evidence.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| actualEffectiveNormalStress | Actual effective normal stress | number | Required |
| callerMatchedJointCompressiveStrength | Caller matched joint compressive strength | number | Required |
| callerIndependentlyAssessedJrc | Caller independently assessed jrc | number | Required |
| callerMatchedResidualFrictionAngleDegrees | Caller matched residual friction angle degrees | number | Required |
Require positive effective normal stress and joint compressive strength in matching units, with normal stress≤strength and nonnegative JRC. Compute JRC×log10(JCS/stress)+supplied residual friction angle. Require this combined angle in [0,90) degrees and multiply stress by its tangent. The residual angle alone is finite but has no separate range guard. No fitting, scale correction or joint-design approval is supplied.
effectiveAngleDegrees=JRC×log10(JCS/normalStress)+residualAngle; peakShearStress=normalStress×tan(effectiveAngleDegrees×pi/180) Apply the field units and exact ordering, boundary and evidence rules above.
| Output field | Meaning | Value type |
|---|---|---|
| result | Structured result containing the calculation or selected reference fields below | object |
| result.conditionalBartonBandisPeakShearStress | Conditional Barton Bandis Peak Shear Stress; use the units, sign convention and calculation stated above | number |
{
"input": {
"actualEffectiveNormalStress": 1,
"callerMatchedJointCompressiveStrength": 10,
"callerIndependentlyAssessedJrc": 5,
"callerMatchedResidualFrictionAngleDegrees": 20
},
"output": {
"result": {
"conditionalBartonBandisPeakShearStress": 0.4663076581549986
}
}
}Limitations and assumptions
The empirical branch and friction-angle convention constrain the calculation. Results depend on the independently established measurement basis and the exact model assumptions above.
Every listed input requires an explicit value. Unexpected fields, incorrect value types, nonfinite numbers and sparse numeric arrays fail validation; tool-specific bounds and alignment rules apply as described above. Extremely large inputs or outputs can also be rejected. An input error is distinct from a successful calculation that reports a false comparison or retains unknown evidence.
Alternative or Complementary methods
Use Geology Tailings Dam Factor Of Safety Calculator to examine a related aspect: Tailings-dam stability depends on loading, pore pressure and an independently assessed failure model.
Use Geology Geomechanics Deformation Modulus Hoek Diederichs Calculator where its separate inputs and scope apply: Hoek–Diederichs deformation estimates depend on the equation version and empirical rock-mass context.
References
Similar or alternative tools
- Geology Tailings Dam Factor Of Safety Calculator
Tailings-dam stability depends on loading, pore pressure and an independently assessed failure model.
- Geology Geomechanics Deformation Modulus Hoek Diederichs Calculator
Hoek–Diederichs deformation estimates depend on the equation version and empirical rock-mass context.