# HOW TO MEASURE LOOSE MATERIAL DENSITY IN THE FIELD

**Material density determines bucket and machine choice**

Construction companies often select the size of machine they believe is required and equip it with a standard bucket, but this approach might short change productivity. The ideal decision sequence for highest productivity is to:

- Identify your production targets.
- Take the greatest
**material density**on the site and match it to the appropriate bucket size and capacity needed to meet the productivity targets. - Choose the machine that will efficiently cycle that bucket.

**The following procedure can be used to determine the loose density of material in the field.**

What you will need:

- A 5 gallon/19 liter capacity pail or bucket
- A water source
- Enough site material to fill the bucket
- A scale
- A marker or pen and paper
- A calculator

**Step 1 – Determine the volume of the pail.**

- Weigh the pail to obtain the empty weight.
- Record the empty weight on the pail for future reference.
- Completely fill the pail with water.
- Weigh the filled pail.
- Subtract the pail empty weight on the bucket from the filled pail weight to obtain the weight of the water in the pail.
- Divide the weight of the water by the density of one cubic foot (62.42796)/meter (1000) to obtain the pail volume in cubic feet/meters.
- Record the volume of the pail on the pail for future reference.

**Formula:**

total weight of pail filled with water – empty weight of pail

density of 1 cubic foot/meter of water

**Step 2 – Measure the loose density of the material.**

- Fill the pail with materials from the site. DO NOT pack.
- Drop the pail to settle the material and eliminate voids.
- Strike off the material so it is level with the top of the pail.
- Weigh the filled pail.
- Subtract the pail empty weight on the bucket from the filled pail weight to obtain the weight of the material in the pail.
- Multiply the weight of the material in the pail by 27.
- Divide the answer in #6 by the volume of the pail (recorded on the pail) to obtain the material density in lbs./cubic yard or kg/cubic meter.

**Formula:**

total weight of pail filled with material – empty weight of pail x 27

pail volume in cubic feet or kg/cubic meter

Additional materials can be found in the Caterpillar Performance Handbook.

Consult your Cat dealer for more information.