Calculate excavation volume for dredging works with advanced inputs. Track bulking, density, and cost clearly. Export results, chart trends, and validate planning decisions instantly.
Enter channel geometry, production assumptions, and cost values. The calculator uses a trapezoidal section and the average end area method.
Trapezoidal cross-sectional area:
A = d (b + z d)
Where:
A = cross-sectional area, d = depth, b = bottom width, z = side slope in horizontal to vertical ratio.
Average end area volume:
V = L (A1 + A2) / 2
Allowance and loose volume:
Over-dredge volume = V × allowance%
Payable volume = V + over-dredge volume
Loose volume = payable volume × (1 + bulking factor%)
Mass and cost:
Estimated mass = payable volume × density
Estimated cost = payable volume × unit cost
| Project | Length (m) | Bottom Width (m) | Start Depth (m) | End Depth (m) | Side Slope | Bulking % | Over-Dredge % |
|---|---|---|---|---|---|---|---|
| Harbor Reach A | 120 | 14 | 2.8 | 3.6 | 1.5:1 | 12 | 5 |
| River Bend B | 175 | 10 | 2.2 | 2.9 | 2.0:1 | 10 | 4 |
| Marina Pocket C | 85 | 9 | 1.7 | 2.1 | 1.0:1 | 8 | 3 |
It estimates in-situ dredging volume from trapezoidal geometry, then adds over-dredge allowance, loose volume from bulking, estimated mass, and a simple project cost.
Side slope is entered as horizontal to one vertical. A value of 1.5 means the sides move 1.5 meters horizontally for every 1 meter vertically.
Separate depths allow the calculator to model a changing section along the dredging length. That improves planning when the bed is not uniformly deep.
Bulking factor accounts for material expansion after excavation. Loose sediment usually occupies more space than in-situ sediment, so disposal and transport plans need this adjustment.
Over-dredge allowance is an added percentage for practical excavation tolerance. It helps cover unavoidable extra removal beyond the design section during operations.
Yes. Enter a unit cost per cubic meter and the calculator multiplies it by payable volume. It is useful for screening estimates, not final contractual pricing.
Yes. The Plotly chart compares in-situ, allowance, payable, and loose volumes. That makes allowance impacts and disposal demand easier to explain to stakeholders.
No. Final dredging design should also use hydrographic survey data, geotechnical findings, sediment behavior, tolerance rules, and site-specific production constraints.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.