Three-lane changing behaviour simulation using a modified optimal velocity model

In real urban traffic, roadways are usually multilane and are divided into fast, medium and slow lanes according to different velocity restrictions. Microscopic modelling of single lane has been studied widely using discrete cellular automata and continuous optimal velocity models. In this paper, we extend the continuous single-lane models (OV model and FVD model) to simulate the lane-changing behaviour on an urban roadway that consists of three lanes. Considering headway difference, velocity difference, safety distance, and the probability of lane-changing intention, a comprehensive lane-changing rule set is constructed. We analyse the fundamental diagram and reveal the faster-is-slower effect in urban traffic induced by lane-changing behaviour. We also investigate the effect of lane-changing behaviour on the distribution of vehicles, velocity, flow and headway. Asymmetrical phenomenon with symmetrical rules on urban roadway and density inversion on the slow lane were also found. The simulation results indicate that lane-changing behaviour is not advisable on crowded urban roadway. It is hoped that information from this study may be useful for traffic control and individual moving strategy on urban roadway. (C) 2011 Elsevier B.V. All rights reserved.