Residual strength: ring shear 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

• ✓ Intercept small (≤ 5 kPa)

Method, formulas and assumptions

• φr through origin = DEGREES(ATAN(SUMPRODUCT([t.s],[t.tr])/SUMPRODUCT([t.s],[t.s]))) = 11.763 °
• φr (free fit) = DEGREES(ATAN(SLOPE([t.tr],[t.s]))) = 11.442 °
• Intercept c′r = INTERCEPT([t.tr],[t.s]) = 1.75 kPa

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