22A Road Gravel

Gravel is rock that is of a certain particle size range. In geology, gravel is any loose rock that is larger than two millimeters (mm) (about 1/12 an inch) in its longest dimension but no more than 63 millimeters (about 2.5 inches). The natural erosion of larger rocks has led to the formation of many gravel deposits. In addition, gravel is now produced by crushing rocks mechanically.


  • Dense graded base under asphalt concrete pavements
  • Surfacing for unpaved driveways, roads and parking lots
  • Dense graded base under portland cement concrete pavements
  • Dense graded base under portland cement concrete slabs


A dense graded base aggregate, produced by screening and crushing, natural sand & gravel. A material formed by the natural abrasion and disintegration of rocks by glacial or riverbed action. The particles are sized from 1″ (25.0mm) to zero (dust).


M-DOT 22A Natural Sand & Gravel conforms to all the requirements of Michigan Department of Transportation (M-DOT) “2003 Standard Specifications for Construction,” section 902

Usage Guide:

The 22A Natural Sand & Gravel should be placed 6″-18″ (150mm-450mm) thick, depending upon ground conditions and design loadings, in lifts not exceeding 8″ (200mm). Prior to the placement of any base material, the grade should be compacted and trimmed to the design density & elevations and be free of any standing water and not in a frozen condition. Base material should be compacted at optimum moisture content (≈6%-8%) to 95%-100% relative density or to the compaction level as specified in the design plans.