Modelling the Traffic Behavior at Grade-Separated Interchanges

Grade separation is an essential feature of intersections between motorways and other high-capacity roads.  This paper describes the development of a microscopic simulation model to investigate the interactions between traffic and geometric variables at such situations.  The model has been integrated within a modular computer program and it has been calibrated and validated with a large data-base. Comparisons with measured data and information from other sources have shown that the model adequately describes the traffic behaviour.  (Author/TRRL)