Inputs
m
m
2.0–3.0 typical
m below ground
kN/m³
For
clay: c = undrained shear strength su, last = α (or 0 to auto). For sand: φ in degrees, last = β (skin) override or 0 for K·tanδ default.
Methods
- α-method (clay, undrained): fs = α·su; α from API: 1.0 if su≤25 kPa, 0.5 if ≥75 kPa, linear between.
- β-method (sand, drained): fs = β·σ'v; β = K·tan(δ), default β = 0.27–0.50 by φ.
- End bearing (clay): qp = 9·su,tip (Skempton).
- End bearing (sand): qp = σ'v,tip·Nq with Nq from φ (Vesic).
- Effective stress σ'v uses buoyant γ below water table.
- Qult = ΣQs + Qp; Qallow = Qult/FS.
Results
Pile Perimeter—
Pile Tip Area Ap—
σ'v at tip—
Skin Friction Qs—
End Bearing Qp—
Ultimate Capacity Qult—
Allowable Qallow—
| Layer | Type | Depth | fs (kPa) | Qs,layer (kN) |
|---|