Technical Reports

FAST/HAL Track Loads Evaluation

  • 01
  • Oct
  • 1991
AUTHOR: David M. Read, Duane E. Otter
SUBJECT: Facilities & Test Equipment, Evaluation
KEYWORDS: Facility for Accelerated Service Testing, Heavy Axle Loads, Vertical and Lateral Force
ABSTRACT: The FAST/HAL Track Loads Evaluation was conducted to quantify vertical and lateral forces at the Facility for Accelerated Service Testing, Transportation Test Center, Pueblo, Colorado, under 33- and 39-ton axle load cars. Vertical rail forces beneath the 39-ton axle load cars were found to be 25 percent to 35 percent higher than those beneath the 33-ton axle load cars. Lead axle lateral rail forces were from 13 percent to 28 percent higher under the 39-ton axle load cars. There were no significant differences in lateral to vertical force (L/V) ratios. The lateral forces and L/V ratios for both the 33- and 39-ton axle load cars were found to be dependent upon lubrication conditions. Corrugated rail was found to induce higher vertical forces than rail with no visible surface defects. The vertical and lateral force measurements were taken using instrumented rail circuits at two separate locations in 5-degree curves. The loads were measured beneath a train of 14 each of 33- and 39-ton axle load cars which was operated at 40 mph to 42 mph. In addition, a pair of instrumented wheel sets was installed in a 39-ton axle load car to measure vertical and lateral forces. The measurements taken with the instrumented wheel sets generally supported those taken at the wayside locations.