Long term performance of road markings on rural roads: guide–lines for maintenance management

A lot of data has been collected concerning road marking properties deterioration in order to develop performance prediction models for correct infrastructure management. In Italy, two types of road markings are mainly used, paint or thermoplastic, based on several components (thermoplastic binder systems, paint, epoxy, methyl-methacrylate, polyester, polyurea, waterborne paint, modified urethane). Vehicle tyres are abrasive and remove paint and thermoplastic markings, but these have different service life, due to their different surface adhesion and skid resistance properties. In the last years, the budget for transport infrastructure has been heavily cut and this has led to a decrease in monitoring and maintenance activities. Thus, road markings have been left in place longer than scheduled. Monitoring of the long-term performance of horizontal markings began in 2008, on behalf of some Italian road authorities, with the aim of focusing on wearing course surface deterioration, carriageway perception and road marking visibility. The project initially included a limited number of sections but has been increased over time (there are now 36 sections). Collected data demonstrated that thermoplastic markings present some advantages in comparison with paint, although they are slightly more expensive. According to the results, guidelines were developed for maintenance management.