California Department of Transportation

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Laboratory Policies and Procedures




Pavement Coring

core rig

Project Development Pavement coring may be required to determine existing structural section information for surface obliteration, widening, etc.

Pavement coring may be required during construction to provide:

  • Correlation of LTMD (Laboratory Test Maximum Density) and nuclear gauge "in place compaction" per CTM 375
  • Density or specific gravity tests per CTM 308 and or 309

If coring is required, provide the following information:

  1. Route, postmile, EA.
  2. Type of material to be cored:
    1. Asphalt
    2. PCC
    3. Underlying Aggregate base/ Aggregate sub base layers
  3. Diameter and depth of core. Maximum core width and depth is 8 inches (200 mm) and 5 feet (1525 mm). The Geotechnical Branch must be contacted for any depth greater than 5 feet.

Contact (707) 445-6355 for more information and availability.