CALIBRATION OF BRAKE FORCE TRAILERS AND SKID-RESISTANCE PHOTO-INTERPRETATION

THE SLOPE CALIBRATION METHOD, USED BY THE DEPARTMENT OF HIGHWAYS, ONTARIO, FOR THE PAST SEVERAL YEARS, HAS SEVERAL DESIRABLE FEATURES. IT ALLOWS FOR THE REDISTRIBUTION OF THE TRAILER LOAD DURING BRAKING; THE PRECISION IS OF THE ORDER OF PLUS AND MINUS 1.0 SKID NUMBER POINT; AND ROUTINE PERIODIC CALIBRATIONS CAN BE PERFORMED IN MINUTES, AND WORKSHOP FACILITIES ARE NOT NEEDED. IN THIS METHOD, THE WHEEL TORQUE IS MEASURED WHILE THE TRAILER WHEEL IS IN A SKID-RESISTING STATE AND THE TIRE PATCH POINT IS RELOCATED. IN OTHER SKID- TRAILER CALIBRATION METHODS THAT USE TORQUE MEASUREMENTS, THE SKID NUMBERS ARE CALCULATED FOR THE WHEEL-HITCH LOAD DISTRIBUTION OF A NONRESISTING TIRE. THE RELOCATION OF THE TIRE PATCH POINT CAN PRODUCE SIGNIFICANT DIFFERENCES IN THE SKID TEST RESULTS OBTAINED BY THE TORQUE MEASURING TECHNIQUE FOR DIFFERENT TIRES. THE DEMANDS ON THE SERVICES OF A SKID TRAILER ARE HEAVY, AND IT IS OFTEN DIFFICULT TO AVOID DELAYS WHEN THE PAVEMENT SKID RESISTANCE OF ACTUAL OR SUSPECTED POTENTIAL ACCIDENT LOCATIONS HAS TO BE EVALUATED. THE DEPARTMENT OF HIGHWAYS IS USING PHOTO- INTERPRETATION OF SKID RESISTANCE, AND IT APPEARS THAT EVEN IN ITS PRESENT STATE OF DEVELOPMENT, THE METHOD HELPS TO REDUCE THE NUMBER OF PROBLEM LOCATIONS BY POSITIVELY IDENTIFYING PAVEMENT TEXTURES IN THE LOWER, MIDDLE, AND HIGHER RANGES OF SKID RESISTANCE. /AUTHOR/

• Record URL:
  http://onlinepubs.trb.org/Onlinepubs/hrr/1971/376/376-010.pdf
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/0309019907
• Supplemental Notes:
  • Sponsored by Steering Committee for Workshop on Anti-Skid Program Management and presented at the workshop. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved.
• Authors:
  • Schonfeld, R
• Publication Date: 1971

Media Info

• Media Type: Digital/other
• Features: References;
• Pagination: p 39
• Monograph Title: Anti-Skid Program Management and Related Papers
• Serial:
  • Highway Research Record
  • Issue Number: 376
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Pavements; Photointerpretation; Skid resistance; Skid resistance tests; Skid trailers; Skidding; Surface course (Pavements); Texture
• Uncontrolled Terms: Skid number
• Subject Areas: Highways; Pavements; Safety and Human Factors;

Filing Info

• Accession Number: 00221635
• Record Type: Publication
• ISBN: 0309019907
• Report/Paper Numbers: HS-011 999
• Files: TRIS, TRB
• Created Date: Jun 5 1972 12:00AM