Laboratory surface texture analysis of road pavements using a mobile phone camera based close-range photogrammetry technique

The wearing course conditions strongly affect road pavements quality in terms of traffic safety and overall functionality. Surface texture can be considered a very strategic aspect to assess road pavement status, in order to predict its degradation and to define an effective maintenance program. Nowadays, common texture assessment approaches are mainly empirical and based on in-situ and/or laboratory direct measurements, thus the quantity and quality of the obtainable information are limited. On the other hand, advanced contactless techniques require expensive and often complicated equipment that can be hardly used in common applications. In this regard, a low budget close-range photogrammetry technique for road pavements 3D surface texture analysis is here proposed. 14 areal texture parameters including depth, volume, distribution and feature indicators have been determined by analysing the 3D models. The outcomes have been compared with those found with the traditional volumetric patch and pendulum tests, and a complete pairwise correlation matrix has been obtained. Volume patch test exhibits a high relationship with different volume and height surface texture parameters, while low-correlations have been found comparing pendulum test with the intrinsic and statistical indicators. The results and their relationships have been commented in-depth along with proposed further research activities.