Role of the use phase and pavement-vehicle interaction in comparative pavement life cycle assessment as a function of context

Abstract

While many pavement life cycle assessment (LCA) studies have been performed over the last decade, one of the most important advances and challenges is quantifying the impacts of various components during the use phase of pavements. The goal of this research is to understand the role of the use phase, particularly pavement-vehicle interaction (PVI), in pavement LCAs, and how use phase impacts vary by context (i.e., for specific climates and traffic levels).We have performed comparative pavement LCAs on two pavement design alternatives for multiple scenarios that encompass a range of locations and traffic levels. The pavement LCA model is probabilistic and the use phase element includes excess fuel consumption from both deflection-induced and roughness-induced PVI. Results from the scenario analysis demonstrate that the use phase can contribute up to 78% of a pavement's life cycle environmental impact and that PVI is the predominant element in the use phase of high-volume roads. Scenario analysis results also indicate that the use phase contributions are highly context sensitive to traffic volume, climate, and vehicle speed. This work contributes to the understanding of the context-dependent use phase impact and reinforces the importance of uncertainty quantification in comparative pavement LCAs.