The South African railways has entered the field of low-speed high-axle-load transportation. The disadvantage is an increase in the track structure maintenance cost or first cost or both. A design procedure based on classical theories, permissible stresses and some qualitative and quantitative performance correlations is explained. This procedure is considered useful for the selection of track standards for a given traffic mix and maximum axle load on the basis of an equivalent maintenance requirement in comparison to a known index condition. The results can thus be utilized to determine the increase in first cost of the track structure for comparison with capitalized operating savings. The procedure lacks a prediction of rail life but attempts to quantify running top performance and tamping maintenance requirements as a function of ballast and formation stresses. For this purpose different traffic mixes are reduced to a common denominator of equivalent theoretical traffic consisting of 18,5 t axles only.

  • Availability:
  • Corporate Authors:

    South African Institute of Civil Engineers

    P.O. Box 1187, 75 Marshall Street
    Johannesburg,   South Africa 
  • Authors:
    • Lombard, P C
  • Publication Date: 1978-9


  • English

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 231-238
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00188339
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Files: ITRD, TRIS
  • Created Date: Feb 27 1979 12:00AM