District 1 Sign and Tower Structure Inspections

Various Counties, Illinois

The scope of services for this project included engineering services required for the inspection of sign and tower structures and for the collection of data and the development of reports.

DB Sterlin performed detailed structural inspections of 290 ancillary highway structures throughout District One. The inspections were based on and in accordance with the Federal Highway Administration Guidelines on the Inspection and Maintenance of Ancillary Highway Structures (FHWA NHI 05-036). The first part of the project consisted of the inspection of 250 High Mast Light Towers. Visual inspection was used to inspect all components of the HMLT including the foundations. A D-Meter tool was used to measure the thickness of the mast wall and Ultra-sonic Testing was used to determine the length and integrity of the anchor bolts. The second part of the project, consisted of the inspection of 40 overhead sign structures located across I-290 and I-90/94. Visual inspection was performed on all components of the structures, including sign panels, panel connections, support truss/frame, end supports and foundation. A D-Meter was used to measure the material thickness of different components of the structures. In addition to the visual and advanced inspection of the structures, inventory data was also collected.