DESIGN FOR RAILROAD BALLAST AND SUBGRADE SUPPORT

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:
  • Find a library where document is available. Order URL: http://worldcat.org/oclc/3519342
• 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

• Features: Appendices; References;
• Pagination: p. 118-120
• Serial:
  • Journal of Geotechnical and Geoenvironmental Engineering
  • Volume: 105
  • Issue Number: GT1
  • Publisher: American Society of Civil Engineers
  • ISSN: 1090-0241
  • Serial URL: http://ojps.aip.org/gto

Subject/Index Terms

• TRT Terms: Acceleration (Mechanics); All terrain vehicles; Ballast (Railroads); Bearing capacity; Deformation curve; Deviatoric stress; Dislocation (Geology); Maintenance; Railroad tracks; Repeated loads; Safety; Subgrade (Pavements); Vehicles
• Uncontrolled Terms: Ballast
• Old TRIS Terms: Deviator stress; Ground distance; Support systems
• Subject Areas: Geotechnology; Highways; Maintenance and Preservation; Railroads; Safety and Human Factors; Vehicles and Equipment;

Filing Info

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