Fatigue assessment of rail underbridges

Many rail underbridges in the NSW system have been in operation for more than 100 years. They have generally experienced increasing design loads over their life. An evaluation of the fatigue resistance in terms of the remaining life is required to assess the adequacy and safety of the structures for future use. Current methods of fatigue assessment include those as specified in design codes, the use of fracture mechanics, and using such techniques as magnetic particle inspection, ultrasonics, acoustic emission, dye penetrant, and metallographic observation. The difficulties associated with the assessments are reviewed and their limitations highlighted. An interdisciplinary approach, that involves material behaviour in the submicroscopic dislocation scale, inspection for cracks, calculation of crack propagation and use of design codes, is needed for the assessment of fatigue life. Some of the techniques were used in the investigation of three rail underbridges for the State Rail Authority and the results are presented. Fatigue prone areas include various riveted and welded details on wrought iron and steel. A comparison of the fatigue life from the methods is made and the significance in variation discussed.

Language

  • English

Media Info

  • Pagination: 14.1-11
  • Serial:
    • Volume: 1

Subject/Index Terms

Filing Info

  • Accession Number: 01434365
  • Record Type: Publication
  • Source Agency: ARRB
  • ISBN: 0855884436
  • Report/Paper Numbers: AP 28/94
  • Files: ATRI
  • Created Date: Aug 24 2012 6:15PM