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. 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 asymmestric longitudinal direction, and (ii) horizontally in the symmetric direction, both alone and also with simultaneous vertical excitation. The existence of expansion joints in the bridge deck proved to have great influence on the response of the structure. Despite the 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 this design are made.

• Corporate Authors:

  University of California, Berkeley

  Pacific Earthquake Engineering Research Center
  Richmond Field Station
  Richmond, CA  United States  94804

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Williams, D
  • GODDEN, W G
• Publication Date: 1976-6

Media Info

• Pagination: 167 p.

Subject/Index Terms

• TRT Terms: Bridge decks; Bridges; Curvature; Dynamic loads; Earth movements (Geophysics); Earthquakes; Elastic waves; Expansion joints; Loss and damage; Mathematical models; Scale models; Seismicity
• Uncontrolled Terms: Dynamic response; Earth movements; Models; Seismic response
• Geographic Terms: California
• Old TRIS Terms: Curved profiles
• Subject Areas: Bridges and other structures; Highways;

Filing Info

• Accession Number: 00159388
• Record Type: Publication
• Source Agency: National Technical Information Service
• Report/Paper Numbers: EERC-76-18
• Contract Numbers: DOT-FH-11-7798
• Files: NTIS, TRIS, USDOT
• Created Date: Sep 20 1978 12:00AM