Estimate the earthwork volumes for your construction project, accounting for soil swell and compaction.
(e.g., 15 for 15% increase in volume after excavation)
(e.g., 85 for 85% compaction, meaning 15% shrinkage)
Understanding Cut and Fill Calculations
Cut and fill is a fundamental process in civil engineering and construction, aimed at balancing the earthwork on a site. The primary goal is to achieve a desired final grade or elevation while minimizing the need to transport material off-site (export) or bring material onto the site (import). This not only reduces costs associated with trucking and disposal/purchase of soil but also minimizes environmental impact.
What is 'Cut'?
Cut refers to the process of excavating or removing earth material from a specific area to lower its elevation to a planned grade. This material is then often used as fill in another part of the site or transported away if there's an excess.
What is 'Fill'?
Fill involves adding earth material to an area to raise its elevation to a planned grade. This material can come from cut areas on the same site, or it may need to be imported from an external source if the site's cut material is insufficient.
The Importance of Volume Calculation
Accurate volume calculations are crucial for:
Cost Estimation: Determining the budget for excavation, hauling, and compaction.
Project Planning: Scheduling equipment, labor, and material deliveries.
Site Balance: Achieving an optimal balance between cut and fill to reduce material transport.
Environmental Impact: Minimizing the carbon footprint associated with trucking soil.
Key Factors: Swell and Compaction
Two critical factors influence the actual volume of soil during earthwork:
Soil Swell: When soil is excavated from its natural, compacted state (in-situ), it becomes loose and aerated, causing its volume to increase. This increase is expressed as a "swell percentage." For example, a 15% swell means that 1 cubic yard of in-situ soil will become 1.15 cubic yards when excavated.
Soil Compaction (Shrinkage): When loose soil is used as fill, it is typically compacted to achieve stability and density. This compaction reduces its volume. The "compaction percentage" indicates how much of the original loose volume remains after compaction. For instance, an 85% compaction factor means that 1 cubic yard of loose fill material will compact down to 0.85 cubic yards of in-place fill. This is equivalent to a 15% shrinkage.
How the Calculator Works
This calculator helps you estimate the volumes involved by taking into account:
Cut Area Dimensions: Length, width, and average depth of the area to be excavated.
Fill Area Dimensions: Length, width, and average height of the area to be filled.
Soil Swell Percentage: To determine the loose volume of excavated material.
Soil Compaction Percentage: To determine how much loose material is needed to achieve the desired compacted fill volume.
The calculator then provides:
The original volume of soil to be cut (in-situ).
The expanded volume of soil after excavation (loose cut volume).
The final compacted volume of soil required for fill.
The total loose volume of soil needed to achieve the compacted fill.
A net balance, indicating whether you have an excess of material (requiring export) or a deficit (requiring import).
Example Calculation:
Let's say you have a cut area of 100 ft x 50 ft with an average depth of 3 ft, and a fill area of 80 ft x 40 ft with an average height of 2 ft. Assume a 15% swell and 85% compaction.
In-Situ Cut Volume: 100 ft * 50 ft * 3 ft = 15,000 cubic feet