The expressway network design problem for multiple urban subregions based on the macroscopic fundamental diagram

With the advancement of urbanization, cities are constructing expressways to meet complex travel demands. However, traditional link-based road network design methods face challenges in addressing large-scale expressway network design problems. This study proposes an expressway network design method tailored for multi-subregion road networks. The method employs the macroscopic fundamental diagram to model arterial dynamics and the cell transmission model to capture expressway dynamics. A stochastic user equilibrium model is further established for route choice, and a decision model is developed to minimize total time spent. Simulations show that new expressways alleviate network congestion, with significant effects in the initial stages. Moreover, route guidance strategies and driver compliance also influence the schemes.