Good soil isn’t judged by appearance. It’s proven through testing.

Once subgrade conditions are approved and fill placement begins, the focus shifts to verification. This is where Field Density Testing (FDT) plays a critical role in earthwork operations.

Field density testing is how we confirm that soil or stone has been compacted to the required density and moisture range according to the project plans. Using specialized testing equipment, our field technicians measure how tightly the material is packed in place and compare the results to project requirements. This tells us whether the ground will perform as intended or if adjustments are needed before construction continues.

On many projects, testing is performed using a small nuclear density gauge, which allows technicians to quickly measure in-place density and moisture without disturbing the soil. In some cases, results are verified using alternative methods, such as a sand cone test, which physically measures soil density to confirm field readings.

As soil or stone is placed, it is spread in uniform lifts, or controlled layers placed and compacted one at a time. This approach allows each layer to be properly compacted and tested before the next layer is added, helping ensure consistent performance throughout the fill.

Our field technicians perform field density testing to confirm two key things:

• The material has been compacted to the required density
• The moisture content is within an acceptable range to achieve the required density and comply with project specifications

Testing is typically performed as each lift is placed, allowing issues to be identified and corrected immediately, before they are buried beneath additional layers. Depending on the project, field density testing may occur continuously or on an as-needed basis, confirming that the ground is being built as designed, not simply assumed to be adequate.

FDT provides the data that allows engineers, contractors, and owners to move forward with confidence, knowing the soil below has been prepared to support what comes next.

Come Build On Our Foundation.