Tackling Tehachapi: Experiments and analyses from the California mountains to the Quebec iron ore fields are quantifying the benefits of friction management

This article describes results of recent analysis in California on the application of wayside top-of-rail friction control along Union Pacific in the famous Tehachapi Loop. The analysis was done in order to determine the best way to reduce track wear while maintaining enough adhesion for trains on a road with 2% grades and several 10-degree turns. Rail life on the curves is generally three to five years or even less. This was the first time multiple wayside units were installed on this type of track, so that the applicator deployment and output rates would be optimized to permit accurate evaluation of their effects. The revenue-service demonstrations were conducted over a short period of time. Key parameters included system reliability, effectiveness under a range of traffic, and interaction with gauge face lubricant and curving factors and rail wear. Early analysis suggests significant reductions in curving forces and low rail-wear rates. Trains operating up-grade received significantly greater reductions than those with sustained air braking on the downhill. Low rail wear was cut by an average of 58%. High rail results were mixed. Another test looked at a new application technology mounted on a locomotive, which may be particularly suited for captive freight fleets. It is mounted on a freight car directly behind the trailing locomotive, which does not impose the same burdens on locomotive maintenance schedule that loco-mounted applicators do. Field testing shows a modified ore car outfitted with a friction modifier applicator was successful in controlling lateral forces for a 160-car train. The article provides details about track conditions, test sites and economic analysis.


  • English

Media Info

  • Media Type: Print
  • Features: Figures; Photos;
  • Pagination: pp 35-37
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 01010974
  • Record Type: Publication
  • Source Agency: UC Berkeley Transportation Library
  • Files: BTRIS, TRIS
  • Created Date: Nov 29 2005 2:50PM