3D-MFD-based traffic assignment

Abstract

The macroscopic fundamental diagram (MFD) and its bi-modal, i.e. car and buses, derivative, the 3D-MFD, are novel tools to model urban traffic from an aggregate or network perspective. Interestingly, traffic assignment based on the MFD has immediately jumped to dynamic traffic assignment models. Although understandable as one of the MFD’s benefits is to being able to model the dynamics of congestion, the MFD can also be used in a static traffic assignment, which usually offer more (mathematical) simplicity in formulation and interpretation. In this paper, we propose a bi-modal static traffic assignment based on the 3D-MFD with a stochastic user equilibrium. In this assignment, we follow the idea of regional paths through several regions, each with a 3D-MFD defined. Regional paths offer at the same time route and mode alternatives between origins and destinations. The interaction between modes is explicitly modeled in the 3D-MFD and thus does not require us to formulate local interactions along streets or routes. We formulated the static traffic assignment as a mixed complementarity problem (MCP) and illustrate its applicability in two case studies.