Excavation Volume Calculator
What is an Excavation Volume Calculator?
What is Excavation Volume?
The Excavation Volume Calculator measures soil or rock cut volume for foundation basements, pipeline trenches, and road subgrades.
Formula
Bank Volume = Length × Width × Depth
Loose Volume = Bank Volume × (1 + Soil Swell Factor %)
Truckloads = Loose Volume ÷ Single Truck Capacity (m³)
Variables Explanation
- L, W, D: Excavation pit/trench dimensions in meters.
- Swell Factor: Soil expansion percentage upon digging (15% for sand, 25% for clay, 40% for rock).
- Truck Capacity: Dump truck tray volume (typically 10 m³ or 14 m³).
How to Calculate
1. Input trench or pit length, width, and depth in meters.
2. Input soil swell percentage (e.g. 20%).
3. Input target dump truck capacity.
4. View in-situ volume, loose transport volume, and required truckloads.
Worked Example
Basement Pit: 25m × 15m × 3m depth = 1,125 m³ In-Place (Bank) Volume.
Clay Soil (25% Swell): Loose Volume = 1,125 × 1.25 = 1,406.25 m³.
Truckloads (10 m³ trucks): 1,406.25 ÷ 10 = 141 Dump Truck Loads.
Practical Construction & Project Controls Use
Earthwork subcontractor BOQ payment, site soil disposal planning, and equipment fleet scheduling.
Understanding the Result
Differentiates in-situ bank cut measurement from hauled truck volume, preventing soil disposal cost disputes.
Limitations & Assumptions
Calculates rectangular pits. Sloped embankment cuts require applying the Prismoidal formula or trapezoidal cross-section averaging.
Frequently Asked Questions
What is the difference between bank volume and loose volume?
Bank volume is compacted soil in its natural ground state. Loose volume is expanded soil after excavation containing air voids.
What is a typical soil swell factor?
Common swell factors: Sand/Gravel = 10-15%, Common Earth = 20-25%, Heavy Clay = 30%, Blasted Rock = 40-50%.
How is trench excavation volume calculated for sloped banks?
Use average width: W_avg = (Top Width + Bottom Width) / 2, then multiply by Length and Depth.
Why is compaction factor important for backfilling?
Loose soil shrinks when compacted back into trenches, requiring 15% to 20% more loose material to fill the bank volume.
How do you calculate truckloads for excavated soil disposal?
Divide total loose soil volume by the rated volumetric capacity of single dump trucks.