# Swell and Shrinkage of Excavated Materials

When building a house you are going to deal with 3 stages of the soil volume you are excavating.

Bank Volume, natural state of the soil.Loose Volume, disturbed state of the soil.

Compacted Volume, volume of the soil after it is compacted.

The change from bank to loose volume is the swell of the excavated material

The change from bank to compacted is the shrink of the excavated material

Bank-----------Swell------------Loose

Bank-----------Shrink-----------Compacted

If you need to remove the excavated material it would help to know the swell percentage for the soil you are excavating. The volume of excavated soil will increase from its natural state(bank) to its disturbed state (loose). Excavating soil and piling it up will loosen it and the volume will increase due to void spaces/air pockets added to the material. If you are excavating an area with a volume of 200 cubic yards consisting of material with a 40% swell, you are actually looking at removing 280 cubic yards. At an average of 12 cubic yards hauling capacity of a truck, you are looking at an additional 6 to 7 truck loads. With larger excavations the cost due to swell can be significant and will add to your needed excavating budget.

The shrink percentage of the soil is useful for determining the amount of material that you need to keep on site for grading and back filling. If the 200 cubic yards of material had a shrink percentage of -10 and you would need to grade or back fill an area with a volume of 90 cubic yards then you would need to keep 100 cubic yards in bank volume of the material and now you would have to haul 140 cubic yards of site.

#### The Calculator

- enter the length of the excavation(feet)
- enter the width of the excavation (feet)
- enter the excavation depth (feet and inches)for uneven depth calculate the average depth
- swell of material (in percentage)
- shrinkage of material (in percentage)
- the amount of material that you can use on site and will be compacted(if needed, in cubic yards)
- the amount of material one truckload can hold (in cubic yards)

#### The Results

- bank volume of material that needs to be excavated in cubic yards
- loose volume of excavated material in cubic yards
- compacted volume of material in cubic yards
- the number of truck loads it will take to remove not needed material of site.
*It will round off the number of loads to the highest number and you could end up with small amount of material in the final truck load.*

### Excavation Calculators

##### Imperial

Number of TruckloadsFuel Consumption for Operating a Machine

Shrink and Load Factor

Spike's Compaction Factor

Swell and Load Factor

Swell and Shrinkage of Excavated Materials

Calculate the Volume of a Pile in Cubic Yards

Calculate the Volume of a Pile in Cubic Yards - Cone Shaped

##### Metric

Number of Truckloads (Metric Measurements)Calculate the Volume of a Pile in Cubic Metres

Calculate the Volume of a Pile in Cubic Metres - Cone Shaped