New Hampshire Department of Transportation On-Call Bridge Painting Inspection Services

Our inspection services have ensured that the proper enforcement of contract specifications is maintained, and the required quality final product is achieved. As an extension of the contract, GPI provided expert advice from its subsidiary, GPI Laboratories that worked with NHDOT in developing proper painting systems as well as aiding in training NHDOT staff in proper environmental regulations and procedures. Some recent projects include:

NHDOT Project No. 22272 Keene, NH: Construction inspection services on field painting activities to blast and paint Corten steel beam ends of the Routes 9/10 Bridge over the Ashuelot River, as well as the full cleaning and repainting of the Routes 9/10/12 over West Street. The inspection consisted of verification of compliance to environmental requirements, abrasive blast clean to SP 10, chloride testing, environmental conditions monitoring, the application of the specified moisture-cured zinc, epoxy, urethane coating system, and verification of dry film thicknesses of each coat in accordance with SSPC PA- 2.

NHDOT Project No. 13567F Portsmouth, NH – Kittery, ME: The Memorial Bridge Replacement project was an $80-million design-build project to replace the existing vertical lift movable bridge structure and approach spans, which carry Route 1 over the Piscataqua River between Portsmouth, NH and Kittery, ME. The project was a collaboration between NHDOT and the Maine Department of Transportation as the bridge carries approximately 12,000 vehicles and 900 pedestrians and recreationalists across the state boundary daily. The 302.5-foot center lift span experiences approximately 4,000 lifts yearly. The design incorporated several innovations, including the first simple truss bridge structure to eliminate gusset plates; lower, less intrusive lift span towers; improved operator visibility and safety; faster lift cycle times; and a 40 to 50-year life-cycle zinc, thermal spray (metalizing) protective coating system. GPI performed a full post-installation evaluation of the coating system on the bridge structure and mechanical parts, identifying rework areas, providing certified coatings quality assurance inspectors to monitor the repair work, and document completion of all coatings repairs, including touch-up of metalized areas.