Diagnosis and treatment of congestion in central urban areas

Abstract The development and dispersal of area-wide traffic jams is a matter of considerable social concern. Work at Middlesex University, supported by EPSRC, has enabled the construction of a simulation model with greater geographical scope than most conventional congestion simulation models. Our simulation concentrates on a holistic view of traffic jam formation in a setting of isotropic flow. In the model, traffic incidents can effectively be introduced anywhere in the network. The growth of traffic jams can be observed using a graphical display and options are included to disperse and control the formation of traffic queues. Simulation results have confirmed that the uncontrolled growth of the traffic jam is both rapid and potentially irreversible. Experiments with dispersing the traffic jam have given greater insight to the ‘gridlock’ phenomena. We suggest a number of possible, practical counter-measures, which would both inhibit the growth process and contribute to the controlled dispersion of queues in congested networks. The effectiveness of the proposed strategies is evaluated via the simulation model and as a result, we provide a coherent set of remedies which would assist in the diagnosis and treatment of central urban congestion problems.