Technical Reports

Distributions of Dynamic Wheel/Rails Under Heavy Axle Loads

  • 01
  • Dec
  • 1998
AUTHOR: D. Li, D. White, M. Ahmadian, M. El-Sibaie
SUBJECT: Facilities & Test Equipment
KEYWORDS: Heavy Tonnage Loop, HAL, TTC, Transportation Test Center
ABSTRACT: Under the Heavy Axle Load (HAL) program funded by the Association of American Railroads (AAR) and the Federal Railroad Administration (FRA), a test activity was initiated in 1997 to study the relationships between dynamic vehicle responses and track geometry conditions. As a first step, analyses were performed on the vast test records of wheel/rail forces and track geometry parameters measured on the High Tonnage Loop (HTL) of the Transportation Technology Center, Pueblo, Colorado. These records were obtained for more than 600 MGT traffic accumulation and were the results of various tests conducted under the HAL program. This paper summarizes the statistical characterization of dynamic wheel/rail forces based on existing HAL measurement records. Dynamic variations of force magnitudes, as well as force distributions in frequency domain are given as a function of track curvature, subgrade support, truck type, wheel position, and traffic accumulation. The results of wheel/rail forces are also compared to the vehicle/track interaction safety standards proposed by FRA.