When a four step model is used in a conventional form, the public transport assignment, and the road assignment are undertaken as an average of the period being modeled, typically, for example, a morning peak two hours. Generalised costs are then skimmed off these for the mode choice phase, with the result that the mode split is also an average over the period. The City Centre study in Wollongong required a more detailed approach as the mode share alters over the day as congestion changes. Accordingly, the model has been set up as a 24 hour model, but split into a number of time slices, incorporating a dynamic road assignment, a dynamic public transport assignment, and a dynamic parking model. In this way, mode choice is able to be changed every few minutes in the peak periods, and the supply of parking at the destination is also incorporated into that phase. This paper describes the specification for the model, the theory behind it, and the way in which the three components are integrated. (Author/publisher) For the covering entry of this conference, please see ITRD abstract no. E213852.
Abstract