OUT-OF-PLANE DISTORTION OF X-TYPE DIAPHRAGM BRIDGES: REVISITED

Some of the Iowa Department of Transportation (Iowa DOT) welded continuous steel plate girder bridges have developed cracking in the negative moment regions at the web gaps with diaphragm connection plates. A research program was initiated to investigate the problem in bridges with X- and K-type diaphragms. This research included a literature search to identify current retrofit methods and an experimental investigation of the problem in X- and K-type diaphragm bridges. The research is still in progress and the results, conclusions, and recommendations are thus preliminary. Three retrofit techniques have been suggested: drilling holes, increasing web gap length, and providing rigid attachment. Drilling holes at the crack tip locations is the one on which the Iowa DOT relies primarily to prevent crack extension. Three bridges with X-type diaphragms were tested. During the summers of 1996 and 1997, these bridges were instrumented using strain gages and displacement transducers to obtain the response at various web gaps and diaphragm elements. Bridges were subjected to truck loading in different lanes with speed varying from crawl to 96 km/h (60 mph).

  • Supplemental Notes:
    • Compendium of Student Papers Presented at the 1997 Transportation Scholar's Conference, Iowa State University, November 14, 1997
  • Corporate Authors:

    Iowa State University, Ames

    Center for Transportation Research and Education
    2711 South Loop Drive, Suite 4700
    Ames, IA  United States  50010-8664
  • Authors:
    • Khalil, A
  • Publication Date: 1997

Language

  • English

Media Info

  • Features: Figures; References; Tables;
  • Pagination: 31 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00770368
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Oct 5 1999 12:00AM