Fieldlink NZ
FIELDLINKNZ
Start 30-day free trial
Civil Hub guide

How to Plan Spoil Removal and Truck Loads

Share

Quick answer

Convert the measured excavation from bank volume to loose volume, then check both truck volume and payload. The usable volume per trip is the smaller of bin capacity and payload divided by loose material density. Divide the loose spoil by that usable volume and round up for whole loads.

Skip the maths — free toolTruck Load Calculator

Separate what is dug from what is carted

Start with the excavation takeoff, then subtract material that will genuinely stay on the job. Keep topsoil, reusable fill and other material streams separate if their destinations or handling differ. Bulking changes the space occupied after digging; it does not create extra material mass.

Formulas

Loose spoil volume = bank volume × (1 + bulking percentage ÷ 100)

Check payload as well as bin size

Use the payload available for the actual vehicle, route and operating conditions, confirmed with the carrier. A volume estimate does not authorise a loading weight. Wet or dense material can reach the payload limit before the bin looks full.

Formulas

Payload-limited volume = available payload ÷ loose density

Usable volume per load = smaller of bin capacity and payload-limited volume

Loads = loose spoil volume ÷ usable volume per load, rounded up

Worked example: payload limits the load

Worked example

Measured spoil: 100 bank m³. Illustrative bulking allowance: 20%.

Loose volume = 100 × 1.2 = 120 m³.

Bin capacity 10 m³; assumed available payload 12 tonnes; loose density 1.5 t/m³.

Payload-limited volume = 12 ÷ 1.5 = 8 m³.

Use 8 m³ per trip: 120 ÷ 8 = 15 loads.

Check the truck cycle against the programme

Add loading, travel out, unloading, return travel and expected queue time. Use measured trips where available. Truck count and daily output depend on both the loading operation and the full cycle, so a faster digger alone may not improve cartage.

  • Confirm the receiving facility accepts the material before starting.
  • Check access, turnaround space and delivery windows with the carrier.
  • Plan for interruptions and record assumptions rather than treating every paid hour as productive.
  • Compare actual load counts and docket weights with the estimate during the job.

Build cartage assumptions into your earthworks estimate, alongside excavation, plant and disposal costs.

Explore earthworks estimating