TIRE TREADWEAR VALIDATION. VOLUME I: TECHNICAL REPORT

The methodology for accelerating tire wear is predicated upon the fundamental fact that tire wear is slip energy dependent. The slip energy invested is a function of the horizontal force required to overcome the vehicle's resistance to motion and the resultant displacement (slip) between the tread elements in the tire contact patch and the aggregate elements in the road surface contact patch. The study concludes that the mechanism of tire wear is not a function of the rolling distance of the tire, but of the sliding distance of the tire tread elements in contact with the road. It reports that the free rolling resistance of these tires requires less energy than the distance the tire is required to slip. The study establishes that road design and surfacing material can play a more significant role in tire wear than tire construction, compound, design or manufacturer. The study confirms the results of a previous DOT program which concluded that accelerating tire treadwear rates by a significant factor does not distort the rank order of the treadwear comparison of those tires tested. The study concludes that a mil of rubber and the miles to which it relates is not a significant indicator of relative tread loss; however, the functional relationship of a unit of tread volume loss to the slip energy invested at the tire/road interface is significant.