A simulation model of road user behaviour and traffic conflicts at unsignalized intersections

This thesis describes a visual microscopic traffic conflicts simulation model for both T and 4-leg unsignalized intersections. The objective of the model is to study traffic conflicts as critical traffic situations and understand the driver's behaviour at these situations. The Author rejected the use of pure gap acceptance criteria to describe driver's behaviour at unsignalized intersections. As an alternative, a combination of some aspects of the gap acceptance criteria and the effect of several parameters including driver’s characteristics such as age and sex and the waiting time are used to describe that behaviour. The model also investigates the effect of different traffic parameters such as volume and speed on the number and severity of traffic conflicts. The model is unique in so far as it stores the traffic conflicts that occur during the simulation for latter study. A graphical animation display is used to show how the conflict occurred and the value of critical variables at this time. The model results were hypothetically validated against previous work in the literature and externally validated using field observations from two unsignalized intersections. In both cases the validation process proved successful.Applied Science, Faculty ofCivil Engineering, Department ofGraduat