Degradation of retro-reflectivity of thermoplastic pavement markings on trunk roads in Ghana

• Main Authors: Daniel Atuah Obeng, Victor Owusu, Yaw A. Tuffour
• Format: Article
• Language: English
• Published: Elsevier 2021-09-01
• Series: Transportation Engineering
• Subjects: Degradation; Retro-reflectivity; Eco-climatic zones; Thermoplastic pavement markings
• Online Access: http://www.sciencedirect.com/science/article/pii/S2666691X21000385

Retro-reflective thermoplastic pavement markings enhance roadway visibility at night and help avoid lane-departure crashes. Markings decay in retro-reflectivity, due to material degradation over time and must be remarked to restore marking visibility. However, road agencies lack data and information on how the material degrades to permit effective management of re-marking interventions. Thus, thermoplastic pavement markings were installed on trunk roads in 3 eco-climatic zones and their retro-reflectivity monitored over time to establish rate of degradation. Retro-reflectivity at any time since marking installation was characterized by a multiple linear function involving initial retro-reflectivity and time. The rate of retro-reflectivity loss was the same for the Coastal Savanna and Forest zones (0.15mcd/m2/lux/day) but significantly different from that for the Northern Savanna zone (0.267mcd/m2/lux/day) at 5% significance level (p<0.05). Additionally, data suggests there is an initial appreciation in retro-reflectivity within the first few months of marking installation before the onset of decay.