Abstract
A theoretical framework is proposed for the traffic assignment problem, which is made up of four causal relationships: (i) the formation of services (route-departure time pairs); (ii) the choices of users; (iii) volume loading from paths to arcs; (iv) traffic flowing. The framework is applied to obtain a simple, macroscopic, dynamic traffic assignment model, the variables in which are: the temporal profiles of volume, price or time for a given arc or route or origin-destination pair, that for each user class. Each causal relationship is formulated as a set of equations. Together, the four sets of equations describe a dynamic equilibrium between trip supply and demand. For the covering abstract see ITRD E126595.