The Calspan Advanced Tire Research Facility was utilized to measure, under controlled laboratory conditions, the braking traction coefficients of ASTM E501 tires as a function of tread depth, velocity and water film thickness. Data were collected using shaved and used (road worn) tires in the slip ratio range from 0 to -1. At constant speed, braking traction coefficients for shaved tires linearly decreased with decreasing tread depth with the rate of loss of traction increasing with velocity and water film thickness. Test results for the used tires did not correlate with those for the shaved tires. Braking traction coefficients for the former exhibited no consistent sensitivity to tread depth at constant speed. The report discusses certain aspects of the tire specimens which may have affected the test results and presents recommendations for mitigating these conditions in future tests. /Author/

  • Supplemental Notes:
    • Sponsored by the Department of Transportation Federal Highway Administration.
  • Corporate Authors:

    Ultrasystems, Incorporated

    Dynamic Science Division, 1850 West Pinnacle Peak Road
    Phoenix, AZ  United States  85027
  • Authors:
    • Gusakov, I
    • Tapia, G A
    • Bogdan, L
  • Publication Date: 1977-7

Media Info

  • Pagination: 41 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00172035
  • Record Type: Publication
  • Source Agency: Federal Highway Administration
  • Report/Paper Numbers: FHWA-RD-77-105 Final Rpt., FCP 35D4084
  • Contract Numbers: Order No 7-3-0010
  • Files: TRIS, USDOT
  • Created Date: Mar 29 1978 12:00AM