FRACTURE MECHANICS IN BRIDGE DESIGN

BRITTLE FRACTURE OF STEEL BRIDGES IS BECOMING MORE COMMON AS DESIGNS BECOME MORE COMPLEX; AS HIGH-STRENGTH THICK- WELDED STEELS DISPLACE THIN, RIVETED PLATES; AS ENGINEERS CHOOSE FABRICATION AND CONSTRUCTION PRACTICES MAINLY TO MINIMIZE COSTS; AND AS SAFETY FACTORS DECREASE WITH COMPUTER DESIGN. THERE ARE THREE BASIC METHODS TO CONTROL FRACTURE: THE USE OF LOW DESIGN STRESSES, THE USE OF TOUGH STEELS, AND AN INSPECTION TO BE SURE NO LARGE FLAWS ARE PRESENT. THERE IS A GROWING FEELING AMONG BRIDGE ENGINEERS THAT FRACTURE TOUGHNESS CRITERION SHOULD BE SPECIFIED FOR BRIDGE STEELS. TO MINIMIZE BRITTLE FRACTURE, THE DESIGNER MUST ELIMINATE GEOMETRIC DISCONTINUITIES THAT ACT AS NOTCHS. INDETERMINATE STRUCTURES ARE USUALLY MORE RESISTANT TO COMPLETE FAILURE THAN ARE DETERMINATE STRUCTURES, E.G., THE KINGS BRIDGE FAILURE IN MELBOURNE, AUSTRALIA, AS OPPOSED TO THE FAILURE OF A PRIMARY MEMBER IN THE SILVER BRIDGE AT PT. PLEASANT, WEST VIRGINIA.

Media Info

  • Pagination: p. 37-41
  • Serial:
    • Volume: 2
    • Issue Number: 8

Subject/Index Terms

Filing Info

  • Accession Number: 00209757
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Apr 8 1973 12:00AM