Effects of Studded Tires on Pavements in Minnesota

During the period of the past five winters in Minnesota, we have witnessed a startling increase in the amount of surface wear in the wheel tracks on many pavements—both bituminous and Portland cement concrete. Previously when similar pronounced surface abrasion occurred it was generally related to some deficiency such as unfavorable con­ struction conditions or materials or mixture design that was marginal for the particular circumstances or traffic demands involved. However, the wear that we are now experiencing is not associated with such causes. It has affected pavements of the highest quality including some that had performed statisfactorily in service for several years before being subjected to studded-tire traffic. Other pavements were affected that were exposed to studs in their initial year of service. The condition has become alarming—developing in the same period in which studded tires have been legally permitted during winter months on Minnesota’s highways. It is quite natural, therefore, that many highway engineers generally blame the wear upon the studs. There are other engineers, however, who ascribe the attrition to in­ creased use of salts and sand contending that the chemicals attack the pavement materials, and that they, together with abrasive sand, make the pavement surfaces readily susceptible to wear from the studs. This argument, however, overlooks the fact that salt and sand have been used freely for a good many years prior to the advent of studs with little or no damage to pavements. Still other proponents of studs take the position that the safety benefits—accidents prevented and lives saved—outweigh any cost of pavement damage that may be incurred.