The discusser comments on the concept of safe bearing pressure and its determination with respect to cyclic loading tests on ballast materials. Safe bearing pressures should be based on a permissible permanent displacement. When the latter exceeds a certain value, maintenance operations are in order. Railroad engineers should establish permissible permanent displacement values for any particular track. The analysis of permanent deformations, critical for the performance of track support systems, require the knowledge of stress-strain properties of ballast and subgrade under cylic loading, as well as the determination of deviator, stresses acting at various depths in the ballast and subgrade. Various computer techniques could be used for this purpose. The discusser also points out some similarities that exist between of-road vehicle-terrain and guided vehicle-track support interactions.

  • Availability:
  • Supplemental Notes:
    • Discussion of Proc. Paper 13471 (January 1978).
  • Corporate Authors:

    American Society of Civil Engineers

    345 East 47th Street
    New York, NY  United States  10017-2398
  • Discussers:
    • Karafiath, L L
  • Publication Date: 1979-1

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00194485
  • Record Type: Publication
  • Report/Paper Numbers: Proceeding
  • Files: TRIS
  • Created Date: Jun 13 1979 12:00AM