Behavior and Fatigue Properties of Metallic Dampers for Seismic Retrofit of Highway Bridges

The objective of this study is to develop an economical solution with metallic dampers for the seismic retrofit of highway bridges in low occurrence seismic zones, such as in the central and eastern United States. Select low carbon steel rods were first tested for their ductile behavior and material strength. Large-scale, tapered rods were then tested for their energy dissipation capability and fatigue strength under regular, irregular and earthquake loads. A full-scale damper made of five tapered rods was designed next for the seismic retrofit of a three-span continuous steel-girder bridge in southeast Missouri; its system performance including joints and connection members was validated with laboratory tests. The damping ratio of tapered rods was shown independent of loading frequency and specimen size; it rapidly increased at small displacements and approached a value of 0.35-0.45 in the range of over 1.8." Even at a displacement of 2.4", the steel rods can survive over 100 cycles of loading with little degradation of their damping property. The full-scale, five-rod damper has been demonstrated to reveal a progressive failure mode that is desirable for earthquake applications. Hysteretic models of Type D rocker bearing were developed for possible consideration in the seismic retrofit design of seismically inadequate highway bridges.

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  • Supplemental Notes:
    • This research was supported by a grant from the U.S. Department of Transportation, University Transportation Centers program.
  • Corporate Authors:

    University of Missouri, Rolla

    University Transportation Center
    1870 Miner Circle
    Rolla, Missouri  United States  65409

    Missouri Department of Transportation

    Research, Development and Technology, 1617 Missouri Boulevard
    P.O. Box 270
    Jefferson City, MO  United States  65102
  • Authors:
    • Chen, Genda
    • Eads, Stephen A
  • Publication Date: 2005-4-15


  • English

Media Info

  • Media Type: Print
  • Edition: Final Report
  • Features: Bibliography; Figures; Tables;
  • Pagination: 94p

Subject/Index Terms

Filing Info

  • Accession Number: 01005715
  • Record Type: Publication
  • Report/Paper Numbers: RDT 05-007, RI 01-028
  • Created Date: Oct 15 2005 6:49PM