Evaluating Pedestrian Safety and Service at Alternative Intersections with Three-Critical-Phase and Two-Critical-Phase Traffic Signals

Intersections constitute an important part of transportation infrastructure, with conventional intersection designs being the most dominant. However, these conventional designs might face operational and safety issues, emphasizing the need for innovative and newer intersection designs to address these challenges. A key concern is the inadequate pedestrian accommodation in conventional intersections, primarily as a result of limited attention to pedestrian needs in older designs. On the other hand, alternative intersection designs may have the potential to improve pedestrian performance by reducing vehicle–pedestrian conflicts, shortening signal cycle lengths, and possibly decreasing pedestrian crossing distances. This paper focuses on the pedestrian safety and service of 10 types of alternative intersections with three-critical-phase traffic signals and two types with two-critical-phase traffic signals in a comparison with a signalized conventional intersection design (with four signal phases). The evaluation was conducted using a wide range of hypothetical scenarios in simulation modeling, the 20-design flag method from the National Cooperative Highway Research Program (NCHRP) Research Report 948, and the conflict point analysis to assess pedestrian performance. The findings suggest that three-phase intersection designs such as the partial median U-turn designs may offer better pedestrian operational and safety performance compared with conventional four-phase designs.