Traffic assignment and network analysis

Abstract

This thesis studies the transportation network, and is divided into three sections. Initially an algorithm is described which finds the user-equilibrium assignment for networks with linear congestion functions where the cost of travel on a link is dependent on the flow in the whole network. Secondly it investigates the sensitivity of the cost of travel and of the flow distribution in the network, to changes in the link congestion function. Combinatorial methods are used for evaluating the results of the sensitivity analysis. This is done with the aim of obtaining fast and efficient algorithms for the evaluation of cost sensitive and paradoxical links. Finally, for networks where the demand is elastic, it describes the catastrophic behaviour of the point representing the user-equilibrium flow distribution under certain cost conditions.