[PhD defence] 09/10/2025 - Lorenzo Brocchini: "A dynamic simulation-based approach to improving traffic efficiency and road safety in roundabout corridors" (UMR ESPACE)

Lorenzo BROCCHINI will publicly defend his thesis entitled: "An approach based on dynamic simulation to improve traffic efficiency and road safety in roundabout corridors", supervised by Didier JOSSELIN and Antonio PRATELLI, on Thursday 9 October 2025.

Laboratory

UMR 7300 ESPACE - Study of Structures, Adaptation Processes and Changes in Space

Composition of the jury

Mr Didier JOSSELIN	Avignon University	Thesis co-director
Mr Antonio PRATELLI	Università di Pisa	Thesis supervisor
Mr Giovanni FUSCO	Côte d'Azur University	Examiner
Mr Alain L'HOSTIS	Gustave Eiffel University	Examiner
Ms Claudia CABALLINI	Politecnico di Torino	Examiner
Mr Reginald SOULEYRETTE	University of Kentucky	Examiner

Summary

The proposed research project is based on the principle that road intersections should no longer be considered as isolated entities, but as integral components of a wider traffic system. This systemic perspective is particularly relevant in the context of roundabout corridors, where interactions between closely spaced junctions have a significant influence on traffic flow, safety and operational performance. The first phase of the study analyses the dynamics of these corridors, focusing on network equilibrium phenomena (such as Wardrop's principles, Braess' paradox and other traffic paradoxes), as well as on key safety and efficiency indicators. The aim is to define a standardised methodology for evaluating roundabout corridors (or road corridors more generally), in order to identify the most efficient and safest configurations.

This approach is based on dynamic simulations and geospatial analyses, using tools such as Aimsun, SSAM and QGIS. In a second phase, we study how emerging mobility and traffic management technologies can be integrated into these corridors to correct inefficiencies and enhance safety. The study focuses in particular on the modelling and testing of Intelligent Transport Systems (ITS), such as access control systems (ACS), in order to assess their potential to improve corridor-wide performance. Both phases are developed through case studies carried out in Pisa (Italy) and Avignon (France), based on field data and detailed simulations. This approach, based on dynamic simulation, demonstrates the complexity of urban environments and ensures the applicability of the proposed methods.

Ultimately, this thesis proposes to rethink the analysis of intersections and road corridors, arguing that roundabout corridors (viewed as integrated systems) provide a relevant angle of analysis for developing more adaptive, efficient and safe transport networks in response to contemporary mobility challenges.

Keywords : flows, capacity, roundabouts, safety, corridors, ITS