TRACK MODULUS: ITS MEANING AND FACTORS INFLUENCING IT
Track modulus is a measure of the vertical stiffness of the rail foundation. Another parameter, track stiffness, is a measure of the vertical stiffness of the entire track structure. Both are related to the track performance. In order to provide a basis for assessing and modifying track performance, the definitions of track modulus and track stiffness are reviewed, and four methods of determining track modulus or track stiffness are discussed. On the basis of analysis with a track structure model, the effects of superstructure and substructure factors influencing track modulus are illustrated and the means of altering track modulus are suggested. Finally, the relationship between the track modulus and track performance is discussed. The subgrade soil conditions are shown to have the greatest influence on track modulus and stiffness. Next in importance are the combined ballast-subballast thickness and the vertical tie-fastener stiffness.
This paper appears in Transportation Research Record No. 1470, Railroad Research Issues.
Monograph Accession #:
Selig, Ernest T
Transportation Research Record
Figures (8) ; References (14) ; Tables (4)
Old TRIS Terms:
Geotechnology; Highways; Railroads
TRIS, TRB, ATRI
Dec 12 2013 2:28PM
More Articles from this Serial Issue: