Check gravity and cantilever retaining wall stability per EN 1997-1. Input wall height, base width, soil parameters, and surcharge — get overturning, sliding, and bearing utilisation bars with FOS values instantly.
Dashed line = FOS 1.5 minimum (EN 1997-1 §6.5). Bar scaled 0–3.
For a cohesionless backfill (c = 0), Rankine's formula gives the active earth pressure coefficient Ka. The total horizontal thrust Pa (kN/m) acts at H/3 from the base for the triangular component, and H/2 for the surcharge component.
| Check | Formula | Min FOS (EN 1997-1) |
|---|---|---|
| Overturning | FOS = ΣMR / ΣMO | ≥ 1.5 (DA1 Comb 2) |
| Sliding | FOS = μ · N / Pa_total | ≥ 1.5 |
| Bearing capacity | FOS = q_ult / q_max | ≥ 2.5 for unfactored |
Given: H = 3.0 m, B = 2.1 m, t = 0.4 m, γ_soil = 18 kN/m³, φ = 32°, q = 5 kN/m², γ_wall = 24 kN/m³.
Ka = (1 − sin 32°) / (1 + sin 32°) = 0.307
Pa_soil = ½ × 0.307 × 18 × 3² = 24.9 kN/m
Pa_surcharge = 0.307 × 5 × 3 = 4.6 kN/m → Pa_total = 29.5 kN/m
Resisting moment from wall + soil weight on heel (see full calc in demo).
Typical result for these dimensions: FOS_overturning ≈ 2.8, FOS_sliding ≈ 1.9, FOS_bearing ≈ 4.2 — all pass EN 1997-1.
Rational Method Q = CiA — Stormwater peak flow from catchment data.
Earthwork Cut/Fill Volume — Cross-section prismoidal volumes.
Pipe Sizing (Manning's equation) — Size gravity stormwater pipes.
Interactive Civil Demo — All three calcs on a pre-seeded site.