THE ROLE OF TREAD DESIGN IN SKID RESISTANCE UNDER WINTER DRIVING CONDITIONS

THE ARTICLE SUMMARIZES THE FINDINGS OF A TWO-SEASON WINTER TEST PROGRAM. THE ROLE OF TREAD DESIGN IN SKID RESISTANCE UNDER WINTER DRIVING CONDITIONS IS CONSIDERABLE, PROVIDING THE TIRE IS NOT OPERATED AT DIFFERENTIAL INTERFACE VELOCITIES THAT EXCEED THE PEAK TRACTIVE EFFORT OF THE TIRE BALANCE BY MAXIMUM TRACTIVE RESISTANCE OF THE MATERIAL ON WHICH THE TIRE IS DRIVEN. THE TIRE MUST CONTINUE TO TURN IF THE TREAD DESIGN IS TO BE MEANINGFUL IN SKID RESISTANCE. A FIGURE IS PRESENTED WHICH ILLUSTRATES THE RELATIVE TRACTIVE PERFORMANCE OF THE SAME PAIRED DRIVE TIRES OVER A RANGE OF SPECIFIC WINTER ENVIRONMENTS. IT MAY BE NOTED FROM THE FIGURE THAT ON WET ICE, NO CHANGE IN TRACTIVE EFFORT OCCURS AS A RESULT OF INCREASED WHEEL SHIP VELOCITY. THESE MEASURED VELOCITIES ARE PURE SLIDING FRICTION VALUES OF A WET TIRE ON WET ICE WITHOUT THE ADDITIVE COUPLING OF ELASTIC DEFORMATION OF THE CONTACT INTERFACE BETWEEN THE TIRE AND THE ICE BECAUSE OF THE THIN FILM OF WATER THAT SEPARATES THEM. ANOTHER FIGURE ILLUSTRATES HOW THE TIRE TRACTION ON DRY ICE IS DEPENDENT ON SLIDING VELOCITY RATHER THAN ON VEHICLE SPEED. IT IDENTIFIES THE CRITICAL LOSS TRACTIVE EFFORT BECAUSE SLIDING VELOCITY INCREASES AFTER PEAK TRACTIVE EFFORT HAS BEEN ACHIEVED. ON WET ICE, THIS TIRES TRACTION IS INDEPENDENT OF SLIDING VELOCITY. THE CHARACTERISTIC TRACTION-SLIDING VELOCITY RELATION IS INDEPENDENT OF DRIVING MODE, WHETHER THE TIRE IS ACCELERATING OR DECELERATING.

Media Info

  • Media Type: Print
  • Features: Figures;
  • Pagination: pp 38-40
  • Monograph Title: Winter driving traction aids
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00217397
  • Record Type: Publication
  • ISBN: 0309022630
  • Files: TRIS, TRB
  • Created Date: Jul 31 1989 12:00AM