Recent advances in tire technology have led to the design of a wide-base tire that has a wider tread than previous designs. These new wide-base tires (445/50R22.5 and 455/55R22.5) result in a load distribution comparable to dual tires. The potential for these wider tires to be more widely adopted is high. Innovative technologies such as the new generation of wide-base tires and other factors related to trucking operations that directly affect pavement damage can be classified into three major components: vehicle-generated load, axle and tire configuration transferring the load, and pavement carrying the load. To fully characterize the damage induced by different tire and axle configurations, the effects of vehicle, tire, and pavement and their interaction must be quantified. Vehicle and tire factors include axle loads, axle spacing, speed, tire inflation pressure, and tire configurations. Pavement parameters include surface roughness, materials properties, layer thicknesses, and subgrade strength. Various research studies investigated the potential pavement damage of wide-base tires as compared to regular dual-tire assemblies. However, until the past five years, all the research studies documented in the literature were conducted on the early generations of wide-base tires. With the recent introduction of the Mechanistic-Empirical Pavement Design Guide (MEPDG), the emphasis in pavement design procedure has shifted from empirical methods to more rational approaches. Therefore, the impact of different vehicle-tire factors on the pavement damage need to be determined using rigorous theoretical modeling capable of simulating field conditions and should be validated utilizing field test response measurements.

* Quantify the impact of vehicle-tire interaction on pavement damage utilizing advanced theoretical modeling that is validated via full-scale pavement testing. This includes the determination of the relative effects of wide-base tires and dual-tire assemblies on pavement performance. * Perform an analysis of the economic, safety, and environmental effects of using wide base tires relative to the impact on pavement performance. * Develop methodology that allows states to assess the impact of wide-base tires on the pavement network.

The research team shall propose an experimental plan to quantify pavement damage due to different tire and axle configurations commonly used in the US. Upon approval of the plan, the experiment will be conducted. This may include accelerated pavement testing to validate the finite element numerical modeling. The validated models, with accelerated pavement test data, can be used to predict damage for various flexible pavement system designs. A comprehensive literature search and synthesis will be needed on the effect of wide-base tire application on pavement damage; starting with the minutes from the "2007 International Workshop on the Use of Wide Base Tires," posted here: http://www.arc.unr.edu/Workshops.html. In addition to pavement response and performance, the effect of wide base tires on vehicle handling, safety, economics, noise and other environmental factors shall be reviewed and documented. The Truck Size and Weight regulations for each state shall also be evaluated for their relevance to usage of wide base tires under study.