<p><p><h2>Commentary</h2>Typical contract pay items and units of measurement used for chemical stabilization of subgrades and base courses include:<br><ul> <li>Subgrade modification measured by the square yard, for all equipment, labor and incidentals necessary to mix, compact, and fine grade a chemically modified subgrade.</li> <li>Cement, fly ash or lime, measured by the ton for material costs.</li> <li>Treated base course measured by the square yard, inclusive of all costs to construct a chemically modified base course.

<p><p><figure id='attachment_2538' style='max-width:448px' class='caption aligncenter'><img class="wp-image-2538 size-full" src="https://www.geoinstitute.org/sites/default/files/geotech-tools-uploads/…; alt="Photograph of a mixer incorporating lime into a subgrade soil." width="448" height="323" /><figcaption class='caption-text'> (Photograph courtesy of Carmeuse Lime &amp