An analytical study, in which the bridge is treated as a multi-degree of freedom system, shows that critical fatigue zones occur in the girder flanges within the end spans. The base metal under the top-flange shear connectors between a field splice and the end of a cover plate, and the base metal at the end of a cover plate in the top and botton flanges, are susceptible to fatigue failure. This anticipated test behavior simulates the concern of the current AASHO Specifications. The sustained stress levels will be equal to the design live load plus impact stresses. Fatigue failure is probable within 600,000 cycles at a stress range of approximately 14 ksi (96 10**6 Pa). A series of steady-state resonance tests are conducted on a single-span composite model to assess the practicability of the proposed fatigue-testing technique. These laboratory tests verify that an electrohydraulic actuator with an attached weight will perform satisfactorily as a loading device to induce resonant vibrations. The performance of the bridge-shaker system is analyzed to insure the capability of this technique to produce the required stress levels for the fatigue test on the prototype bridge.

  • Availability:
  • Corporate Authors:

    Society for Experimental Stress Analysis

    21 Bridge Square
    Westport, CT  United States  06880
  • Authors:
    • Salane, H J
    • Duffield, R C
    • McBean, R P
  • Publication Date: 1976-12

Media Info

  • Features: References;
  • Pagination: p. 468-474
  • Serial:
    • Experimental Mechanics
    • Volume: 16
    • Issue Number: 12
    • Publisher: Society for Experimental Mechanics
    • ISSN: 0014-4851

Subject/Index Terms

Filing Info

  • Accession Number: 00153241
  • Record Type: Publication
  • Source Agency: Engineering Index
  • Files: TRIS
  • Created Date: Oct 29 1977 12:00AM