Evaluation of pavement surface texture at the network level

In this study, variations in surface texture depth within a given roadway project and across different projects were studied. Network-level surface texture data were collected on the highway network in using a 3D laser system (LCMS). Differences in mean texture depth (MTD) were estimated for five surface types (Portland concrete cement, PCC; Superpave mixes, SM-9.5A & SR-12.5A; Chip seal; Ultra-thin bonded asphalt surface, UBAS) considering the random effects of project location, surface age and annual average daily traffic. Variations in surface texture were also investigated at the horizontal curves. In addition, the relationship between the texture depth and the skid number obtained by the ASTM skid trailer were investigated. Results show that there are significant differences in average texture depth within a project and across projects. Highest MTDs were obtained for UBAS and lowest for PCC. At the network level, skid number did not correlate well with the MTDs, irrespective of surface type. However, project-level correlation is quite acceptable.