Geo~FS
Ultimate & allowable bearing capacity for strip, square, and circular footings (Terzaghi, 1943). Outputs qₕ, qₐₗₗ, and allowable column load Qₐₗₗ. Water-table and weak-soil conditions are flagged automatically.
The five core inputs. Hover the symbols if unsure what each means.
Optional, but important in Jeddah and the wider Saudi region.
Enter the column / wall load to check it against the allowable capacity.
Recalculates as you type.
Standard general-shear values. The active row matches your φ; values between rows are log-interpolated.
| φ (°) | Nₐ | Nₘ | Nγ |
|---|
Factor values vary slightly between references/codes. Use a preferred local table if required.
Scope & limits. Classical Terzaghi (1943), shallow foundations (D₣/B ≤ 1), general shear failure. The local-shear option applies reduced parameters (c* = ⅔c, tan φ* = ⅔ tan φ) for loose/soft soils. Water-table correction follows the standard three-case method (γ′ = γ − γₘ). For sabkha, collapsible, or otherwise problematic soils common to the region, classical values are indicative only — verify with CPT or plate-load testing. Default inputs are illustrative placeholders.