A DYNAMIC SIMULATION-BASED APPROACH TO IMPROVE TRAFFIC EFFICIENCY AND ROAD SAFETY IN ROUNDABOUT CORRIDORS

The following research project is based on the premise that road intersections should no longer be considered as isolated entities but rather as integral components within a broader traffic system. This system-based perspective is particularly relevant in the context of roundabout corridors, where the interactions between closely spaced junctions significantly influence the overall traffic flow, safety, and operational performance. The first and foundational phase of the study investigates the dynamics of roundabout corridors, with a focus on network equilibrium phenomena (such as Wardrop’s Principles, Braess Paradox and other known traffic paradoxes) and on key metrics of safety and efficiency. The objective is to establish a standardised methodology to assess roundabout corridors (or better road corridors in general) globally, enabling the identification of the most effective and safe design configurations. This methodological framework relies on dynamic simulations and geospatial analysis, employing tools such as Aimsun, SSAM, and QGIS to explore how "roundabout systems" behave under real-world conditions. In the second phase, the research examines how emerging mobility and traffic management technologies can be integrated into these corridors to address inefficiencies and improve safety. The study focuses in particular on the modelling and testing of Intelligent Transportation Systems (ITS), such as Ramp Metering Systems (RMS), to evaluate their potential to enhance performance across entire corridor networks. Both phases are developed through in-depth case studies in Pisa (Italy) and Avignon (France), using traffic data collected in the field and detailed simulations. This dynamic simulation-based approach ensures that the results reflect the complexity of urban environments and support the wider applicability of the proposed methods. Ultimately, this thesis aims to reframe the way intersections and corridors are analysed, arguing that roundabout corridors (when viewed as integrated systems) offer a powerful basis for developing more adaptive, efficient, and safer transport networks in line with contemporary mobility challenges.