Paste 5–10 station elevations and design grades. Get cut volume, fill volume, and balance point instantly. Uses the prismoidal (average end area) method — the standard approach for road and site earthworks.
| Station (m) | Existing RL (m) | Design RL (m) |
|---|---|---|
| 0 | ||
| 25 | ||
| 50 | ||
| 75 | ||
| 100 | ||
| 125 | ||
| 150 | ||
| 175 | ||
| 200 |
The average end area (prismoidal) method divides the earthworks alignment into prisms between consecutive cross-sections. Each prism's volume is the average of the two end areas multiplied by the length between stations.
Where A₁ and A₂ are the cut or fill areas at successive stations, and L is the distance between them. The method is conservative — it slightly over-estimates volumes compared to the prismoidal formula, which is acceptable for budgeting.
| Station (m) | Existing RL (m) | Design RL (m) | Net height (m) | Type |
|---|---|---|---|---|
| 0 | 12.5 | 12.0 | +0.5 | Cut |
| 25 | 11.8 | 11.8 | 0.0 | Balance point |
| 50 | 11.2 | 11.6 | −0.4 | Fill |
| 100 | 10.1 | 11.2 | −1.1 | Fill |
| 150 | 11.5 | 10.8 | +0.7 | Cut |
| 200 | 12.8 | 10.4 | +2.4 | Cut |
For a 6 m wide road: at station 0→25, A₁ = 0.5 × 6 = 3.0 m², A₂ = 0.0 m², V = (3.0 + 0.0)/2 × 25 = 37.5 m³ cut. Continue for each interval, separate cut and fill.
Rational Method Q = CiA — Peak stormwater flow from catchment parameters.
Retaining Wall Stability (EN 1997) — Overturning, sliding, bearing checks.
Pipe Sizing (Manning's equation) — Size the stormwater pipe for your Q.
Interactive Civil Demo — All three calcs on a pre-seeded 0.8 ha site.