Developing a three-level circular economy framework to measure circularity for meso-level assessment in pavement construction

The transport sector significantly contributes to global resource consumption and CO2 emissions, with pavement construction playing a key role. While circular economy principles have been adopted, existing research primarily addresses macro-level policies and micro-level implementations, leaving meso-level assessment underexplored. Establishing an industry-accepted circular economy system for pavement construction is fundamental for improving the overall circularity index and integrating these principles across all dimensions. This study develops a three-level conceptual model to systematically measure circularity in the pavement construction sector. The model is based on an extensive literature review, standards analysis, and discussions with expert panels. Utilizing the spherical fuzzy analytic hierarchy process framework, this approach is applied for the first time in the pavement construction sector to reduce uncertainty and bias. Moreover, the study synthesizes feedback from 11 key stakeholders, including pavement construction companies, consulting firms, and academic experts from multiple countries, to assess the meso-level circularity index. The results reveal a circularity index of 56.9 %, indicating moderate integration of circular economy practices within the industry and highlighting critical areas for improvement. Additionally, the social indicator, despite having a relatively low weight, demonstrates high implementation potential, suggesting that prioritizing it through policy interventions could lead to short-term gains. The meso-level evaluation model bridges the gap between macro-level policies and micro-level implementation, providing decision-makers and companies with actionable insights into the industry's sustainability status. Furthermore, the proposed model integrated with spherical fuzzy analytic hierarchy process offers a valuable reference framework for promoting circular economy practices in other industries.