Laboratory evaluation of aggregate polishing as a function of load and velocity. Application to the prediction of damages on skid resistance of road surfaces due to trucks and passenger cars

Skid resistance of road surfaces depends mostly on pavement texture. This texture is usually divided to two components: microtexture and macrotexture. Microtexture refers to the small-scale texture of the road aggregate component while macrotexture refers to the large-scale texture of the road as a whole due to the aggregate particle arrangement. Both components contribute to the generation of friction between tyre and road. However, due to traffic, the first-cited component is continuously polished over the road's life. Maintaining that microtexture depends greatly on the aggregates used in the wearing course, the traffic level and the vehicle velocities. This work tries to quantify the influence of these three parameters on skid resistance degradation. Different specimens fabricated from different types of aggregates are submitted to different polishing pressure levels and velocities. From experimental results, an updated version of an existing model of skid resistance evolution is thereby proposed and validated. As a possible application of the new model, a prediction of damages induced by truck and passenger car traffic on skid resistance is proposed.