Technical Reports

Vertical Track Modulus: Test Results and Comparison of Analysis Techniques

  • 01
  • Nov
  • 1979
AUTHOR: J. Choros, A.M. Zarembski, I. Gitlin
OFFICE: RPD
REPORT NUMBER: FRA/ORD-79/34
SUBJECT: Track
KEYWORDS: Vertical Track Modulus, Vertical Track Stiffness, Load-Deflection
ABSTRACT: A vertical track response test was conducted at the AAR Track Structures Dynamic Test Facility. This test was intended to characterize the behavior of the track structure under increasing vertical loads. It was also intended to evaluate the different techniques available for the calculation of the vertical track modulus. The response of the track was obtained by monitoring track deflection under increasing vertical loads. This load and deflection data was then used to calculate vertical track modulus, track stiffness and track compliance. Three widely used techniques were utilized to calculate the vertical modulus. The results of the test indicate that the modulus of the track is related to the level of loading; thus identical track can give different modulus values for different load levels. of the three different techniques used to calculate track rnodulus, the beam- on-elastic-foundation technique required only one deflection value whereas the others required considerably more data.

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