An Integrated LCCA-Circularity Framework for Evaluating Sustainable Flexible Pavements

The road construction sector plays a vital role in economic development but is a major consumer of non-renewable resources such as aggregates, bitumen, and cement. To address sustainability challenges, this study presents an integrated evaluation framework combining Life Cycle Cost Analysis and the Material Circularity Indicator to support decision-making in flexible pavement design. The framework was tested on a key road artery in Greater Tunis, using real-world data from four experimental pavement structures incorporating reclaimed asphalt and recycled concrete aggregates. The methodological novelty lies in assigning monetary value to circularity through a dimensionless Reducing Factor derived from the Material Circularity Indicator, adjusting the Net Present Value of each design alternative. Results show that pavement solutions using recycled materials achieved up to 30% improvements in circularity and a reduction in life cycle costs of approximately 25% compared to conventional designs. In addition, a sensitivity analysis over different relevant parameters also proves the robustness of the proposed framework. These findings underscore the technical and economic viability of circular pavements and demonstrate how integrating CE principles from the design phase can lead to more sustainable infrastructure investments. The proposed tool offers practical relevance for policymakers and road authorities aiming to reduce material consumption, lower costs, and promote circular economy adoption in infrastructure development.