FREFLO: A MACROSCOPIC SIMULATION MODEL OF FREEWAY TRAFFIC

Abstract

Three categories of simulation models for freeway traffic have been developed in the past: microscopic, mesoscopic, and macroscopic. Microscopic models represent individual vehicle movements; masoscopic models represent platoon movements; and macroscopic models represent traffic flow in terms of aggregate measures such as density, space-mean-speed, and flow rate. This paper discusses a model in the macroscopic category that is particularly useful for evaluation freeway operations. The model is described in mathematical detail for basic flow simulation, ramp metering and diversion, surveillance, and representation of freeway incidents. Computation of performance measures is also detailed. The simulation model, FREFLO, which is based on the model equations presented, is then described and illustrated with a sample run. /Author/