Pay Quantities: Bank / Loose / Compacted

V_{L} = V_{B} (1 + s), V_{C} = V_{B} (1 - s_{h})

Contracts specify pay in bank, loose, or compacted. Swell s: bank→loose. Shrinkage sh: bank→compacted. Never mix units when multiplying by unit price.

$V B$: Bank (in-situ) volume
$s$: Swell (decimal)
$s h$: Shrinkage (decimal)

Step-by-step solved example

1000 LCY at $8/LCY. Swell 25%. Bank CY and cost?

Bank / loose / compacted sections of the same earthwork.

1. Bank
VL=VB(1.25) → VB=1000/1.25=800 BCY.
2. Pay
If paying loose: $8000; if bank $8 would be different — read the spec. Cost at $8/LCY=$8000.

Answer: 800 BCY; $8000 if paid as 1000 LCY

10 practice questions

0/10 correct

1.20% swell means 1 BCY becomes

2.Shrinkage 15%: 1 BCY →

3.Load factor is often

4.500 BCY, s=0.25: LCY=

5.Pay ‘in the bank’ means measure

6.A shrink of 10% and swell of 25% on the same soil

7.Unit price $4/BCY on 1200 BCY is

8.Truck capacity 12 LCY, load factor 0.80: bank per load

9.Mass-haul ‘freehaul’ is paid inside

10.Compacted fill needed 2000 CCY, sh=0.20: borrow bank=