This report was prepared as part of the Improved Track Structures Research Program managed by the Transportation Systems Center. The report presents results from a parametric study of track response using a comprehensive track analysis model. Track response parameters include rail and tie bending moments, rail displacement, tie rail seat load, and the distribution of stresses in the ballast and subgrade. The effects of variations in tie size, tie spacing, ballast depth and rail fastener stiffness are presented in graphs suitable for track design trade-off studies. Alternative wood and concrete tie track configurations are evaluated using equivalent maintenance criteria. Maintenance criteria for track surface deterioration were reviewed to select ballast and subgrade stress parameters which can be related to track settlement rate for service loads. Formats for cumulative settlement criteria are evaluated using available laboratory data for the behavior of ballast and subgrade materials under repeated loads. Track lateral strength requirements for wood and concrete tie track are also discussed.

Media Info

  • Features: Appendices; Figures; References; Tables;
  • Pagination: 118 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00175999
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Report/Paper Numbers: DOT-TSC-FRA-77-75 Intrm Rpt., FRA-ORD-77-75
  • Contract Numbers: DOT-TSC-FRA-1044-1
  • Files: NTL, TRIS, USDOT
  • Created Date: Jul 19 1978 12:00AM