PREDICTIVE MODELS FOR ROAD CRASHES AT INTERSECTIONS

This report deals with the development of appropriate predictive models for crashes at intersections capable of being used in planning purposes. It begins with a brief review of past studies into the relationship between crashes at intersections and traffic flow. All crashes occurring between 1988.1991 at 115 signalised intersections and 10 roundabouts in metropolibn Adelaide are assembled in a database. Summary descriptive statistics are provided showing the proportion of crashes by the main crash types. Comparison between the crash situations at signalised intersections in Adelaide and Perth (WA) is provided in tabular fom. Crosssectional study providing a comparison between the crash situation at roundabouts and signalised intersections with similx traffic flow is presented. Non linear and multiple linear regression methods are used to develop models for Lotal intersection crashes and the main collision types at signalised intersections. The lrequency of each of the main crash types are related to traffic flow movements contributing to the occurrence of that type of collision. The report concludes with a set of guidelines to be adopted in developing models for the valious crash types at intersections.