Infinite slope (static & pseudo-static) 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

• ✗ Static FS ≥ 1.5
• ✗ Pseudo-static FS ≥ 1.1

Method, formulas and assumptions

• σn = γz(cos²β − kh sinβ cosβ); τ = γz(sinβ cosβ + kh cos²β)
• u = m·γw·z·cos²β (seepage parallel to slope)
• FS = [c′ + (σn − u)tanφ′]/τ
• ky by bisection where FS = 1

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