Characterizing directional traffic-induced wear of road pavements

Abstract

Traffic-induced wear of road pavements is known to possess directional characteristics. Quantitative characterization of wear directionality in terms of surface texture properties has practical significance in the study of wear mechanisms and driving safety analysis. However, the pavement texture parameters and indices in use today are unable to reveal the directional characteristics of pavement wear. This study proposed a texture statistic, the Directional Wear Index (DWI), to measure pavement wear directionality based on a laser scanned image of a pavement surface. First, macrotexture peaks that were likely to be subjected to traffic abrasive actions were identified as primary peaks using the concept of topographic prominence. Next, a slope ratio was calculated to characterize the shape of a primary peak. DWI was determined as a function of the prominence-weighted sum of the shape codes of all the primary peaks of the surface analyzed. The calculated value of DWI defines both the direction and the magnitude of directional wear of the pavement wear. The proposed concept and DWI calculation procedure were validated using field measured data of actual in-service pavement segments with known directional wear characteristics.