Fatigue-Life Evaluation of a High-Speed Railway Bridge with an Orthotropic Steel Deck Integrating Multiple Factors

The driving security of trains at high speeds is among the pivotal issues significantly affected by the smoothness of rail lines. For high-speed railway steel bridges, the fatigue cracking of typical positions under the rail lines will reduce the stiffness of the deck plate, inducing the smoothing of the rail lines. In this paper, a new theoretical approach is proposed that integrates the fatigue assessment of a typical welded joint for high-speed railway steel bridges in service. Based on the strain history data recorded by a structural health monitoring system, the theoretical approach includes various factors, including stress concentration, environmental corrosion, and train flow. Upon application in an actual high-speed railway bridge with an orthotropic steel deck, the approach was used to conduct determinative and reliable fatigue-life evaluation of the bridge. A static-load experiment was conducted to obtain the stress distribution around the weld and the difference in stress between the positions of the weld and strain gauge. The effect of environmental corrosion integrated two aspects: increased stress and reduced fatigue resistance. Without consideration of train-weight growth, in conclusion, the fatigue life of a typical welded joint will be infinite even if the train flow grows constantly. In addition, the fatigue life of typical welded joints, determinative or reliable, may be less than the designed service period when the growth rate of the train weight reaches 5%.

Language

  • English

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  • Accession Number: 01602009
  • Record Type: Publication
  • Files: TRIS, ASCE
  • Created Date: Apr 4 2016 3:02PM