EFFECTIVENESS OF EXISTING BRIDGE DESIGN METHODOLOGY IN RESISTING EARTHQUAKES--PHASE IV: EXPERIMENTAL MODEL STUDIES ON THE SEISMIC RESPONSE OF HIGH CURVED OVERCROSSINGS

An experimental model study relating to the seismic resistance of large multi-span curved overcrossings of the type which suffered heavy damage during the 1971 San Fernando earthquake is reported. This report is one in a series to result from the investigation, "An Investigtaion of the Effectiveness of Existing Bridge Design Methodology in Providing Adequate Structural Resistance to Seismic Disturbances." The feasibility of developing a model to satisfy the necessary similitude requirements of such a complex structure, and also capable of being tested on the 20 ft x 20 ft (6.1 m) shaking table at the University of California, is outlined. The small amplitude dynamic characteristics of the microconcrete model, a 1/30 true-scale version of a hypothetical prototype, are examined and for this elastic range the experimental results compared satisfactorily with those predicted analytically. The response of the model is described for a series of progressively more intense simulated seismic excitations applied i) horizontally in the asymmetric longitudinal direction, and ii) horizontally in the symmetric direction, both alone and also with simultaneous vertical excitation. Existence of expansion joints in the bridge deck proved to have great influence on the response of the structure. Despite inclusion of strong ductile restrainers across these joints, they were subjected to severe damage caused by multiple impacting in both torsional and translational modes. Some recommendations concerning the design are made. /Author/

  • Supplemental Notes:
    • Sponsored by the Federal Highway Administration, DOT.
  • Corporate Authors:

    University of California, Berkeley

    Campus Research Office, 118 California Hall
    Berkeley, CA  USA  94720
  • Authors:
    • Williams, D
    • GODDEN, W G
  • Publication Date: 1976-6

Media Info

  • Pagination: 153 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00172036
  • Record Type: Publication
  • Source Agency: Federal Highway Administration
  • Report/Paper Numbers: FHWA-RD-77- 91 Final Rpt., FCP 35A2012
  • Contract Numbers: DOT-FH-11-7798
  • Files: TRIS, USDOT
  • Created Date: Mar 29 1978 12:00AM