Mechanistic-empirical pavement design to include mechanical performance of rubberized asphalt pavements in the use stage of life cycle assessment

Abstract

The use phase of road pavements includes fuel consumption, urban heat island, and leaching. Life cycle assessment (LCA) often omits the use phase for its complexity. The use phase should also consider the durability of the asphalt mixtures. This study used the Mechanistic-Empirical Pavement Design to include the durability of five asphalt mixtures (control, styrene-butadiene-styrene - SBS, polymer coated rubber - PCR dry and wet, and devulcanized rubber - DVR) in the LCA of 1-mile road pavement over 50 years. Considering only the impact of the mixture production, the control mix had a carbon footprint 12.9 % lower than the other mixtures. When including the durability, the control mixture's carbon footprint was 69 % and 84 % higher than SBS and PCR dry mix, respectively. This study showed the importance of including the mechanical performance of the asphalt mixtures to better evaluate the environmental impact of road pavements over the service life.