Cut and Fill Operations

What is Cut and Fill?

Cut and fill is moving soil from high areas (cut) to low areas (fill) to achieve target grade. It's the foundation of all earthwork: roads, pads, foundations, site prep.

Bank Density vs Loose vs Compacted

• Bank cubic yards (BCY): Material in-place, undisturbed (dense)
• Loose cubic yards (LCY): Material after digging (volume increases)
• Compacted cubic yards (CCY): Material after compaction (volume decreases)

Swell Factor

When you dig soil, it expands. Example: 100 BCY becomes 120 LCY (20% swell).

Volume Calculation Steps

1. Measure cut depth, width, length → calculate cubic yards
2. Apply swell factor (e.g., 1,000 BCY × 1.25 = 1,250 LCY)
3. Calculate fill volume needed
4. Apply compaction factor (material shrinks when compacted)
5. Balance: goal is cut ≈ fill (within 5-10%)

Equipment Selection

• Dozer: Push, fast, initial grading. Not precise.
• Excavator: Precision dig, load trucks. Accurate but slower.
• Loader: Load trucks and stockpiles.
• Best approach: Excavate (precision), load trucks (efficiency), spread with dozer (coverage)

Common Mistakes

• Ignoring swell → underestimate volume
• Poor balance → too much fill or not enough
• Not accounting for compaction → need more material than you think
• Pushing on unstable slopes → failure risk

Related Reading

• Volume Calculation
• Slope Stability
• Dozer Operation