MassDOT Field Inspection & NDT of Highway Sign, ITS Inspection
AI has been performing inspections and non-destructive testing of support structures for overhead signs and traffic signals as well as Intelligent Transportation System (ITS) and lighting structures for MassDOT from 2012 to the present. To date, AI has inspected 1,980 signs, lights, ITS structures, and traffic signals along Interstates 90 and 93 in District 6, Routes 3, 24, and 138 in District 6, and Interstate 190 in District 3. These structures are being inspected for the first time and the inspectors must collect and record basic inventory information including structure type, material, location, and finally the current condition of the structure components. AI’s inspection reports will form the baseline to guide future inspections.
Each structure’s precise location is recorded using sophisticated global positioning system (GPS) equipment as part of the inventory process. The structures are then inspected hands-on starting at the base of each post, up the post and along the horizontal arm. These inspections include the foundation and the safety features such as guardrail or barriers that protect the traveling public from colliding with the structures. All the anchor rods are ultrasonically tested for cracks and indications; all anchor nuts and leveling nuts are sounded and checked for tightness. The wall thickness of each steel post is checked just above the base plate using a D-meter and recorded and compared with the original thickness for possible section loss from corrosion. All the sign panels, signal heads, camera equipment and lighting fixtures are inspected to make sure the attachments are sound. Minimum vertical clearance is measured and recorded for each structure. Critical findings are reported immediately to MassDOT.
Most of the structures consist of steel or aluminum and some lighting structures are concrete. For the metal structures, when a crack is observed or suspected a dye penetrant test is performed to establish the extent of the crack for future monitoring if it does not warrant immediate repair or removal. The deliverable on this project are inspection reports prepared in the MassDOT 4D Database complete with all inventory information, nondestructive test results, condition rating of the structure components, narrative descriptions of the conditions and sketches and photographs.
2012 - Present
- 4D Database
- NBIS Guidelines
- Fracture Critical
- Special Inspection
- Sign Structure Inspection