Excavation Volume and Spoil
Estimate bank volume from project dimensions, then apply a user-defined swell percentage to calculate loose spoil volume. Results can be shown in cubic metres or cubic yards.
Trenches and Battered Excavations
Trenches use a trapezoidal cross-section. Rectangular battered excavations use the prismoidal formula based on bottom, mid-depth and top areas instead of assuming a similar-pyramid frustum.
Truck Loads and Cost
Enter truck capacity to estimate full loads and the final partial load. Separate bank excavation, loose disposal, transport and mobilisation costs remain visible in the calculation.
Side Slopes Are User Inputs
The calculator does not choose a safe slope. Soil, groundwater, depth, adjacent loads, temporary works and jurisdiction-specific rules must be assessed independently.
Excavation Calculator FAQ
What is bank volume?
Bank volume is the geometric volume of material before excavation. Loose volume applies the swell percentage entered by the user.
How is a sloped trench calculated?
The calculator derives the top width from the bottom width, depth and H:V side slope, then multiplies the trapezoidal cross-sectional area by trench length.
How is a battered rectangular excavation calculated?
The bottom, mid-depth and top plan areas are combined with the prismoidal formula, which is suitable when the dimensions vary linearly with depth.
Can I combine several excavations?
Yes. Add rectangular excavations, trenches, sloped excavations, circular pits or custom plan areas to one quantity estimate.
Does the tool recommend safe side slopes?
No. Entered slopes are quantity assumptions only. Excavation stability and support require a project-specific safety assessment.
Can I export the estimate?
Yes. Export a concise PDF calculation or an Excel workbook with summary, excavation and assumption sheets.
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