A Programmable Procedure to Calculate Number of Traffic Conflict Points at Highway Intersections

• Authored by:  J. Lu
• Co-authored by:  X. Ge , F. Pan , C. Li

Traffic conflict points at intersections are the points at which traffic movements intersect (including crossing, merge, and diverge). Numbers and distribution of conflict points have been used to evaluate intersection access management designs and safety performance. Traditionally, determination of numbers of conflict points for different traffic movements has been based on manual methods, which causes the difficulty for computerized procedures to evaluate safety performance of different access management designs. Sometimes, a programmable procedure may provide better solutions as compared to manual methods. This paper presents a programmable procedure for the calculation of numbers of conflict points, which could be used as a basis for computerized procedure. Concepts of virtual movement lanes and intersection quadrants are introduced to specify types of intersections, traffic lane configurations, and traffic movement regulations. Based on the concepts, the calculation models for traffic conflict points at signalized and unsignalized intersections can be obtained. To support the procedure, case studies are presented in the paper. The procedure presented in the paper can be programmed into a computer program for the purpose of computerized evaluation of intersection safety and design performance of different access management or control approaches. 

Lu, J., X. Ge, F. Pan and C. Li, “A Programmable Procedure to Calculate Number of Traffic Conflict Points at Highway Intersections,” 90th Annual Transportation Research Board Meeting, Washington, D.C. (2011)