Life Cycle Thinking-Informed Approach to Support Pavement Design Decision Making

Abstract

Sustainable design of pavements requires the satisfaction of performance criteria, cost, and environmental impacts. Improvements in each of these aspects cannot always be achieved at the same time, necessitating the explicit consideration of trade-offs in design. This paper identifies and improves trade-offs between different aspects of pavement design through an expansion of the boundaries of the problem to identify related life cycle flows that can be used to establish the most optimal solutions where multiobjectives are explicitly considered. An illustration of the method is provided for the design of a benchmark asphalt mixture, considering its global warming potential (GWP), production costs, reclaimed asphalt pavement (RAP) content in design, and its performance characteristics in an asphalt pavement with respect to thermal cracking, rutting, and alligator cracking. The proposed method is used to holistically identify solutions on a Pareto frontier so that the GWP of the mixture can be reduced without compromising performance. The outcomes provide decision makers with guidelines on margins of tolerance and indicate ways to reduce the environmental impacts of a design without negatively impacting performance.