Dynamic Performance of Cantilevered Sign Trusses for Fatigue

Cantilevered sign truss structures are susceptible to fatigue issues at the connection between the pole and mast arm due to vibrations caused by galloping, vortex shedding, natural wind gusts, and truck-induced wind gusts. Calculations carried out by engineers at KDOT indicate that box connection details should be susceptible to fatigue; however, no fatigue cracks have been observed. Recently, it has been proposed to remove walkways on cantilevered sign trusses to prevent vandalism. It is not evident what impact walkway removal will have on the aerodynamic/aeroelastic properties of cantilevered sign trusses and how this will influence fatigue performance. To understand the risk of potential failures, there is a need to evaluate these sign structures and develop strategies that result in lower levels of vibrations to mitigate fatigue problems. Research has considered wind loads in sign structures [1,2], but the impact of walkway removal remains unclear. The proposed work is an important step in ensuring safe cantilevered sign trusses.

    Project

    • Status: Active
    • Funding: $63,355
    • Sponsor Organizations:

      University of Kansas, Lawrence

      Department of Civil Engineering, 2006 Learned Hall
      Lawrence, KS  United States  66045-2225
    • Managing Organizations:

      Kansas Department of Transportation

      Eisenhower State Office Building
      700 SW Harrison Street
      Topeka, KS  United States  66603-3754
    • Project Managers:

      Ingalls, Michael

    • Performing Organizations:

      University of Kansas, Lawrence

      Department of Civil Engineering, 2006 Learned Hall
      Lawrence, KS  United States  66045-2225
    • Principal Investigators:

      Fadden, Matthew

    • Start Date: 20170701
    • Expected Completion Date: 20190630
    • Actual Completion Date: 0

    Subject/Index Terms

    Filing Info

    • Accession Number: 01662453
    • Record Type: Research project
    • Source Agency: Kansas Department of Transportation
    • Files: RiP, STATEDOT
    • Created Date: Mar 8 2018 12:35PM