The Application of an Elastic Demand Equilibrium Model for Assessing the Impacts of Urban Road User Charging

Abstract

Road user charging has been proposed as a solution to the uncontrolled growth of traffic and congestion in urban areas. In the absence of evidence from real world applications, modelling techniques provide the best information about the potential impacts and benefits of different charging approaches. This research has employed an elastic demand network equilibrium model, as part of the well established SATURN suite of computer programs, to represent a series of alternative road user charging systems which have been proposed for practical application.

Results have been obtained for both the impacts of charges on the volume and spatial distribution of road travel demand and for aggregate measures of network performance, such as travel distances, times and costs. Some interesting issues have emerged regarding the overall performance of charging systems in comparison with prior expectations and the specific impacts of charges related to travel conditions, which attempt to approximate the economic theories of marginal cost pricing. In addition, doubts are raised regarding the ability of steady-state equilibrium models to provide plausible representations of behavioural responses to charges which may vary significantly in time and space. It is suggested that alternative modelling techniques may provide superior user response predictions.

Citation

Milne, D. (1998), "The Application of an Elastic Demand Equilibrium Model for Assessing the Impacts of Urban Road User Charging", Griffiths, J.D. (Ed.) Mathematics in Transport Planning and Control, Emerald Group Publishing Limited, Leeds, pp. 411-419. https://doi.org/10.1108/9780585474182-040