Materials laboratory testing & field inspection

Materials and Fabrication Inspection staff test and approve a variety of materials for use in construction projects.

Materials and fabrication inspection

Materials and Fabrication Inspection staff test and approve a variety of materials for use in construction projects. Often, these materials have protective coatings such as liquid coating, powder coating, thermal spray zinc coating, hot dip galvanized zinc coating, or anodizing. We also:

  • Complete visual inspections of materials to assure compliance to contract provisions
  • Ensure that tape measures, digital calipers, survey equipment and other construction-related equipment provide accurate measurements
  • Collect samples of reinforcing bar, paint, bolting material, etc. for testing
  • Witness testing of concrete at the fabricator's facility
  • Review material certifications and documentation as required by contract.

Chemical Materials Testing

At the Chemistry Laboratory, we conduct a variety of tests on the following roadway construction materials to determine conformance with WSDOT Standard Specifications:

  • Cement (chemical analysis)
  • Joint materials
  • Paints
  • Fencing
  • Epoxies
  • Bearing pad material
  • Pigmented sealers

Bituminous Materials Testing

The Bituminous Materials Section staff perform a variety of tests on the following roadway construction materials to determine conformance to WSDOT Standard Specifications:

  • Hot Mix Asphalt (HMA) mix design
  • Warm Mix Asphalt (WMA) mix design
  • Mix design conformation testing
  • Performance Graded (PG) binder testing
  • Emulsified asphalt testing

The Bituminous Materials Section also provides forensic testing on asphalt binders and mixtures, new bituminous technology evaluation, nuclear density gauge service and calibration, and special project assistance.

166,800 electric vehicle

registrations in Washington in 2023, up from 114,600 in 2022.

87 wetland compensation sites

actively monitored on 918 acres in 2023.

25,000 safe animal crossings

in the Snoqualmie Pass East Project area since 2014.