In-Situ Load Testing of Bridge A6358 Osage Beach, MO

This report presents the assessment of a high performance steel bridge located at the Lake of the Ozarks in Miller County, Missouri. The bridge number is A6358 and it is located on U.S. Route 54/Osage River. Two different modern techniques for structural health monitoring were applied for this purpose, in order to advance their field validation process. Displacements of the girders during the pouring of the concrete deck and a diagnostic load test, conducted after the bridge completion, were evaluated using an optical non-contact measurement technique based on an automated total station system. The setup included a total of 22 reflecting prisms mounted onto the bottom flange of the girders, plus four reference targets placed outside the bridge superstructure. Strain and temperature distributions along some of the girders were measured during the diagnostic load test using a fiber optic distributed Brillouin sensing technique. The method is based on the Brillouin phenomenon, which defines a linear relation between the axial strain in an optical fiber, and the corresponding shift in the frequency distribution of the scattered Brillouin light generated when an optical impulse runs through a fiber. A single optical circuit, comprised of bare fibers and a custom-made novel glass fiber reinforced polymer tape with embedded sensing fibers, was installed on the web of the girders at different depths, along two continuous spans. Experimental deflection and strain data were verified to be consistent with each other and allowed to evaluate the actual girder distribution factors. The comparison between experimental and theoretical results based on the AASHTO LRFD bridge design specifications allowed for the establishment of the safety of the structure, although pointing out a significant drop in the expected behavior of one of the external girders, which may call for further assessment.

Language

  • English

Media Info

  • Media Type: Print
  • Edition: Final Report
  • Features: Appendices; Figures; References; Tables;
  • Pagination: 66p

Subject/Index Terms

Filing Info

  • Accession Number: 01006292
  • Record Type: Publication
  • Report/Paper Numbers: UTC R124-3, Report No. 00001104, RDT05-003
  • Contract Numbers: DTRS98-G-0021 (Grant)
  • Files: TRIS, USDOT, STATEDOT
  • Created Date: Oct 13 2005 11:45PM