Are Stabilization & Modification the Same?

Get Out the Dictionary

Let’s take the easy approach and dissect the words.  As defined at, Stabilization means to make stable, steadfast, or firm and Modification is the making of a limited change in something.  Stabilization & modification are similar, but not the same, especially when it comes to soil and sub-grades.

Soil Stabilization

What do we make stable, steadfast, or firm?  Sub-grades. Sub-grades are the top soil layer below pavements or building slabs that support aggregate base.  We mostly stabilize soils in 12” to 16” lifts using cement or fly ash.  When performing stabilization we aim to achieve a strength gain that can be measured.  The verified strength can be utilized in the structural design of pavement and building slab cross sections that are supported by stabilized sub-grade .

stabilization & modification

Soil Modification

Remember the definition?  It’s the making of a limited change in something.  The something we want to change is soil.  When we modify soil we most often change it by drying it.  Very often, excavators need to utilize fill from their jobsite that is too wet to compact.  We use the same process and many of the same products that we use in stabilization, but the most popular to modify soil are lime kiln dust and quicklime.  The main goal for modification is to dry the soil to a moisture level that allows compaction to be completed properly.  Modification can be performed in a single lift, to help pass a proof roll, or in multiple lifts to build a site’s building pad or parking lot.

stabilization & modification

Soil Stabilization

Improved Construction Schedule – Make your sub-grade rain resistant; the stabilized soil will remain strong through rain events and can be worked on soon after they occur.

Better Value – Reduce the thickness of aggregate, asphalt, or concrete needed to meet structural design requirements, and reduce your cost.

Soil Modification

Improved Construction Schedule – Modification is faster and more reliable than disking and drying on projects with tight deadlines.

Better Value – Cheaper, faster, stronger, and better for the environment than export of unsuitable soil, and import of quality fill to build your site.


Protection from Future



Engineered to Specific

Structural Requirements



Time Savings



Cost Savings


Get the latest news and educational articles delivered right to your inbox. Join the Rock Solid elist today!

Want to Learn More?

Visit and check out their Treatment Resource Center on Soil Stabilization & Soil Modification.

Or Contact Us.  We Love to Talk Soil Improvement.

Written By: