Evaluation of Torsional Vibrations in Steel Truss Bridge Members

Long and torsionally slender H-shaped cross sections, often used as tension members in truss bridges, can exhibit wind-induced torsional motions. These motions have produced high-cycle fatigue damage for some bridges. There is limited information available to evaluate the torsional response on the fatigue performance of the members and connections. An in-service bridge with a documented history of wind-induced torsional motions in the verticals was instrumented to capture the wind speed and direction that induced torsional motions in the verticals. Sensors also captured the rotation angle amplitudes and numbers of cycles. Laboratory tests were conducted on a full-size replica of a vertical-and-chord connection to establish the relationship between rotation and normal stresses in the cross section from warping restraint at the connection locations. Analytical methods were shown to accurately predict the rotations and warping stresses along the member length. Applying the experimental and analytical results, the stress ranges were determined for the field-measured torsional responses, and the fatigue potential was evaluated. The results showed the measured stress ranges are near the constant amplitude fatigue limit, but the large cycle counts and frequency of events in the historical wind record that could produce torsional response indicate the need for continued monitoring and a long-term mitigation strategy.

• Record URL:
  https://doi.org/10.1061/(ASCE)BE.1943-5592.0000688
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/oclc/32947845
• Supplemental Notes:
  • © 2014 American Society of Civil Engineers.
• Authors:
  • Keller, Philipp
  • Higgins, Christopher
  • Lovejoy, Steven C
• Publication Date: 2015-9

Language

• English

Media Info

• Media Type: Web
• Features: References;
• Pagination: 04014102
• Serial:
  • Journal of Bridge Engineering
  • Volume: 20
  • Issue Number: 9
  • Publisher: American Society of Civil Engineers
  • ISSN: 1084-0702
  • Serial URL: http://ojps.aip.org/beo

Subject/Index Terms

• TRT Terms: Aerodynamic force; Bridge members; Failure; Field tests; Laboratory tests; Sensors; Structural health monitoring; Torque; Torsion; Truss bridges; Wind
• Subject Areas: Bridges and other structures; Highways; Maintenance and Preservation; I24: Design of Bridges and Retaining Walls;

Filing Info

• Accession Number: 01541366
• Record Type: Publication
• Files: TRIS, ASCE
• Created Date: Oct 21 2014 9:20AM