THE EFFECT OF TIRE CONSTRUCTION ON BRAKING FORCE COEFFICIENTS

RADIAL AND CROSS PLY TIRES HAVE BEEN COMPARED IN TERMS OF PEAK AND SLIDE BRAKING FORCE COEFFICIENTS AT CAR SPEEDS BETWEEN 50 AND 130 KM/H (30 AND 80 MILE/H) ON A RANGE OF WET SURFACES: ONE COMPARISON WAS MADE WITH TIRES HAVING A WINTER TREAD PATTERN AND ANOTHER WITH TIRES HAVING A SIPED PATTERN. ALTHOUGH THERE WERE DIFFERENCES BETWEEN THE BRAKING PERFORMANCE GIVEN BY THE WINTER TREAD TIRES AND THE SIPED TIRES, THE DIFFERENCES PRODUCED BY THE TYPE OF TIRE CONSTRUCTION WERE NOT GREATLY INFLUENCED BY THE TYPE OF TREAD. THE RADIAL PLY TIRES GAVE HIGHER PEAK BRAKING FORCE COEFFICIENTS ON ALL THE SURFACES THAN DID THE CROSS PLY TIRE. THE DIFFERENCES BETWEEN THESE COEFFICIENTS WERE ALMOST INDEPENDENT OF SPEED AND WERE LEAST ON THE COARSE-TEXTURED SURFACES AND GREATEST ON THE FINE-TEXTURED SURFACES, RANGING FROM ALMOST ZERO TO ABOUT 0.1. THE RADIAL PLY TIRES GAVE HIGHER SLIDE BRAKING FORCE COEFFICIENTS ON THE FINE-TEXTURED SURFACES BUT LOWER COEFFICIENTS ON THE COARSE- TEXTURED SURFACES THAN DID THE CROSS PLY TIRES BUT THE DIFFERENCES WERE SMALLER THAN FOR THE PEAK COEFFICIENTS RANGING FROM ABOUT ZERO TO ABOUT 0.05. /RRL/A/

• Supplemental Notes:
  • Rrl Rpt Lr 224, 14 PP, 12 FIG, 2 TAB, 11 PHOT, 2 REF
• Corporate Authors:

  MINISTRY OF TRANSPORT, LONDON (UK)

  ,    
• Authors:
  • Meades, J K
• Publication Date: 1969

Subject/Index Terms

• TRT Terms: Bias ply tires; Braking; Coefficients; Force; Moisture content; Pavements; Radial ply tires; Speed; Surface course (Pavements); Texture; Tires
• Uncontrolled Terms: Wet conditions
• Old TRIS Terms: Radial tires
• Subject Areas: Highways; Pavements; Vehicles and Equipment;

Filing Info

• Accession Number: 00206838
• Record Type: Publication
• Source Agency: Road Research Laboratory /UK
• Files: TRIS
• Created Date: Apr 16 1970 12:00AM