An energy-based approach to predict skid-resistance progression

The assessment of the evolution of skid resistance and texture of surface pavement plays a key role in a modern Pavement Management System. However, the problem can not be straightforwardly tackled since different factors (e.g. material related, environmental, traffic related, etc) affecting the skid resistance and macro-texture progression can be detected. Therefore, empirical models derived from experimental measures have been developed in the past. Actually, following skid resistance and macro-texture measurements carried out within a 5-6 year long period on a specific road section, regression curves are usually derived as a function of cumulated traffic. The main drawback of this approach is related to its effectiveness being strictly dependent on the context in which the expression has been derived and to the extended monitoring period required. In this paper, a different methodology for the development of skid resistance empirical deterioration model has been proposed. According to this methodology, the surface damage induced by traffic is related to the dissipated frictional energy of the tribological system describing the tire-road interface. Basing on this approach, within a very few period, skid resistance measurements have to be carried out on several road sections in which similar bituminous mixes of different age have been laid. Making use of a suitable equivalency criterion for damage induced by vehicles, it becomes possible to effectively describe the deterioration state of a specific bituminous mix as a function of cumulated damage induced by the traffic and of mix properties.