This paper describes the major features of an optimisation model which can be used to design public transport networks. Design problems that can be solved with the model involve the redesign of either a part of a network or a complete network and the assignment of frequencies. The model consists of an additive procedure in which the decision to incorporate a route in the network or to increase the frequency of a route is based on an economic criterion which can also be regarded as an estimate of the lagrange multiplier of the optimisation problem. A major advantage of the model is that the different design problems are solved with one single optimisation process. Furthermore, the optimisation process is kept understandable and the model is suited for use on a personal computer. Some results of the model are presented.
Abstract