Integrated Implementation of Innovation Intersection Designs [May 2020]

US Transportation Collection2020PDFTech ReportRouphail, Nagui M.Cunningham, ChrisDavis, William J.Warchol, ShannonAhmed, IshtiakNorth Carolina State UniversityCitadel, the Military College of South CarolinaUnited States. Department of Transportation. University Transportation Centers (UTC) ProgramSoutheastern Transportation Research, Innovation, Development and Education Center (STRIDE)United States. Department of Transportation. Office of the Assistant Secretary for Research and TechnologySoutheastern Transportation Research, Innovation, Development and Education Center (STRIDE)United StatesAlternatives analysisBikewaysCrosswalksCyclistsHighway designIntersectionsMicrosimulationPedestriansRight turnsStoppingTraffic delaysTravel timeLeft turnsBicyclesContinuous Flow intersectionDisplaced left turnAlternative intersectionRCUT Multimodal effectsProject F69A3551747105/16/2017 to 5/21/2020This study evaluated the performance of pedestrian-bicycle crossing alternatives at Continuous Flow Intersections (CFI). Further, a comparison was also performed of CFI crossing types against a standard intersection designed to provide an equivalent volume-to-capacity ratio. Three CFI crossing alternatives were tested, namely Traditional, Offset, and Midblock crossings. In total, 24 alternative scenarios were generated by incorporating two bicycle path types, two right-turn control types, and two CFI types. These scenarios were analyzed through microsimulation on the basis of stopped delay, travel time, and number of stops. Simulation results revealed the Offset crossing alternative incurred the least stopped delay for all user types. The Traditional crossing generated the least number of stops. The Midblock crossing can be considered as a supplement to either the Offset or Traditional crossing depending on the specific origin-destination patterns at the intersection. The exclusive bicycle path performed better than the shared-use path in most cases. However, these general trends may vary significantly at the route-level analysis. When compared with an equivalent standard intersection, aggregated results showed significant improvement for all CFI crossing types with respect to travel time and stopped delay, but the standard intersection had an equal or fewer number of stops. Future research includes incorporating pedestrian-bicycle safety, comfort, and the relative effects of these crossing alternatives on vehicular operations. Finally, a summary of the multimodal aspects of Reduced Crossings IU-Turn (RCUT) intersections, as studied by researchers at The Citadel is provided in Appendix B of this report. The reduction of the number of conflict points to as few as eight provided by RCUT intersection configurations was found to be beneficial to all roadway users including, motor vehicle traffic, pedestrians, bicyclists, and transit users.120