Calculator Inputs
Formula Used
This calculator assumes a rectangular bund, dimensions measured at the outer toe, a uniform section around the perimeter, and identical inner slope behavior on all inner faces.
Base width, B = C + H(Si + So)
Inner floor length, Li = L - 2B
Inner floor width, Wi = W - 2B
Cross-section area, A = H[C + 0.5H(Si + So)]
Centerline perimeter, P = 2[(L - B) + (W - B)]
Wall material volume, Vw = A × P
Usable height, Hu = H - F
Usable capacity, Vc = HuLiWi + Si(Li + Wi)Hu² + (4/3)Si²Hu³
Where: L = outer length, W = outer width, H = wall height, C = crest width, Si = inner slope, So = outer slope, and F = freeboard.
How to Use This Calculator
- Select meters or feet.
- Enter the outer length and outer width at the bund toe.
- Provide wall height, crest width, inner slope, outer slope, and freeboard.
- Add a wastage allowance for extra fill or construction contingency.
- Press the calculate button to show results above the form.
- Review wall volume, adjusted fill, containment capacity, and the Plotly graph.
- Use the CSV or PDF buttons to export the active result set.
Example Data Table
| Case | Outer L (m) | Outer W (m) | Height (m) | Crest (m) | Slopes (H:1V) | Wall Volume (m³) | Usable Capacity (m³) |
|---|---|---|---|---|---|---|---|
| Fuel tank bund A | 40.0 | 30.0 | 2.5 | 1.0 | 1.5 / 1.5 | 1258.750 | 951.104 |
| Chemical storage bund B | 55.0 | 38.0 | 3.0 | 1.2 | 2.0 / 1.5 | 2693.520 | 1917.899 |
| Compact process bund C | 28.0 | 22.0 | 1.8 | 0.8 | 1.0 / 1.0 | 385.632 | 493.909 |
FAQs
1. What does this bund wall volume calculator estimate?
It estimates bund wall cross-section area, wall material volume, adjusted fill volume, and usable containment capacity for a rectangular earth or embankment bund.
2. Which dimensions should I enter?
Enter the outer toe length and width, wall height, crest width, inner slope, outer slope, and freeboard. Keep all linear inputs in the same unit system.
3. Why is freeboard included?
Freeboard reduces the usable liquid height below the crest. It provides a safety margin for waves, settlement, overtopping risk, and operational uncertainty.
4. What does the wastage allowance change?
The wastage allowance increases the wall material volume to reflect practical fill needs, trimming losses, overbreak, handling losses, or site construction contingency.
5. Does the calculator handle circular or irregular bunds?
No. This version is built for rectangular bunds with a uniform section. Circular, polygonal, or irregular layouts need different geometry and corner treatment.
6. Why can inner floor dimensions become invalid?
If the wall is too high, the crest too wide, or the slopes too flat for the selected outer size, the calculated inner floor becomes zero or negative.
7. Is the result suitable for final engineering approval?
Use it for planning, checking, and early estimating. Final design should still be reviewed against project drawings, soil data, codes, and containment requirements.
8. What does the Plotly graph show?
It compares wall volume, adjusted fill volume, and usable containment capacity. That helps you judge construction quantity against available containment performance quickly.