EFFECTS OF TIRE DEFLECTION ON REAR-AXLE TORQUE

Data were obtained in the study of an 18-wheel western-type log truck outfitted with central tire inflation (CTI) and carrying a highway load. Operating on grades of 20 and 25%, drive shaft torque was monitored to quantify stress levels on the drive train while varying tire deflection. Information is provided on the limits of additional traction to be gained through the use of tire deflection when operating on steep terrain--without excessive tire slip or vehicle maintenance. Torque levels for each grade and deflection combination are presented. A combination of steep topography and escalating road construction costs have led to the use of shorter, steeper roads. In order to reach landings of harvesting operations with a minimum road length, spur roads are often constructed in the 20 to 25% slope range. Haul roads exist with grades of 15 to 20%. An assist vehicle is often appraised when grades exceed 16%. Using the proper tire deflection for the application (based on speed and load) appears feasible through the use of CTI systems. Benefits have been seen in reduced vehicular damage to forest roads and increased tire life. An additional benefit realized with the use of CTI is improved traction on some road surface types because of the increased tire tread length.

• Record URL:
  http://onlinepubs.trb.org/Onlinepubs/trr/1991/1291vol1/1291-076.pdf
• Record URL:
  https://scholar.google.com/scholar_lookup?title=EFFECTS+OF+TIRE+DEFLECTION+ON+REAR-AXLE+TORQUE&author=R.+Simonson&publication_year=1991
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/030905715
• Supplemental Notes:
  • This paper appears in Transportation Research Record No. 1291, Fifth International Conference on Low-Volume Roads, May 19-23, 1991, Raleigh, North Carolina, Volume 2. 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:
  • Simonson, Robert
• Conference:
  • International Conference on Low-Volume Roads, 5th, 1991, Raleigh, North Carolina, USA
• Publication Date: 1991

Media Info

• Features: Figures; References;
• Pagination: p. 335-341
• Monograph Title: Fifth International Conference on Low-Volume Roads May 19-23 1991, Raleigh, North Carolina, USA; volumes 1 and 2
• Serial:
  • Transportation Research Record
  • Issue Number: 1291
  • Publisher: Transportation Research Board
  • ISSN: 0361-1981

Subject/Index Terms

• TRT Terms: Axle load force; Axles; Conferences; Forest roads; Haul roads; Inflation; Logging trucks; Low volume roads; Reduction (Chemistry); Service life; Slopes; Tire pressure; Tires; Torque; Traction; Trucks; Vehicle rear end
• Uncontrolled Terms: Grades
• Old TRIS Terms: Rear axles; Reduction; Tire life; Truck pavement damage
• Subject Areas: Design; Highways; Motor Carriers; Pavements; Vehicles and Equipment; I22: Design of Pavements, Railways and Guideways; I90: Vehicles;

Filing Info

• Accession Number: 00611814
• Record Type: Publication
• ISBN: 030905715
• Files: TRIS, TRB
• Created Date: Aug 31 1991 12:00AM