This paper details the initial findings of research to develop more advanced urban roundabout accident prediction models that will enable more accurate evaluation of urban roundabout accident benefits. It is planned that these models will predict vehicle accidents on urban roundabouts in NZ in relation to traffic volumes and geometric variables - it is proposed that the inclusion of geometric variables will greatly improve the accuracy of these equations. Accident prediction model forms and findings from the United Kingdom, Australia, and NZ are outlined. A considerable database has been collated including traffic movement volumes, geometric site characteristics, and accident data for 95 urban roundabouts throughout NZ. Some initial results from the database are presented and discussed. It is envisaged that these new accident prediction models based on traffic volumes and geometric layout variables will be incorporated into a future amendment of Transfund's Project Evaluation Manual (PEM), which uses benefit/cost analyses to determine road improvement priorities in NZ. (Author/publisher) For the covering entry of this conference, please see ITRD abstract no. E210413.
Abstract