⛏️ Excavation Calculator

Bank (BCM) is the volume of soil as it sits undisturbed in the ground. Loose (LCM) is the expanded volume after excavation — soil swells 15–35% when disturbed. Compact (CCM) is the volume after re-compaction (fill), which is typically 5–15% less than bank volume. These conversions are critical for hauling and fill calculations.

Clay: 30–40%, Sandy loam: 20–30%, Dense sand: 10–20%, Gravel: 10–15%, Rock (blasted): 30–50%. The default 25% covers most common soils. Always use site-specific values when available from geotechnical reports.

For a trapezoidal excavation with slope H:V, the average width = bottom width + (slope ratio × depth). The volume uses the average cross-sectional area. This calculator automatically adds the slope volume to the rectangular base. For example, a 1:1 slope on a 5m wide, 2m deep cut adds 2m to each side at the top, giving an average width of 7m.

A standard 10-wheel dump truck holds 8–10 m³ (10–13 yd³) of loose material. Articulated off-road dump trucks (ADTs) hold 15–35 m³. Small 6-wheel trucks hold 4–6 m³. Always use loose volume (not bank) for truck load calculations since that is what fills the truck bed.