Evaluating and Comparing the Impact of Connected and Autonomous Vehicles on Conventional Intersections and Superstreets

Connected and Autonomous Vehicles (CAVs) have been one of the most promising technologies that are expected to bring significant changes to the transportation infrastructures. One of the main features of CAVs is that they can travel on roads without human intervention, and by doing so, traffic crashes caused by human errors can be eliminated and significant economic benefits can be reaped. Also, with the capabilities to communicate with surrounding vehicles and infrastructures, CAVs can travel through road junctions and segments more smoothly and efficiently, which will, in turn, increase the road capacity and reduce fuel consumption. To become better prepared for this transition, transportation engineers and researchers have begun to evaluate how well CAVs can perform in existing transportation infrastructures, such as freeways, on/off ramps, intersections, and roundabouts. Nevertheless, there have been few studies that have assessed the performance of CAVs in the environment of innovative intersections. The main goal of this research is to mitigate this research gap by conducting a simulation-based study to examine the operational performance of superstreets, one of the popularly implemented innovative intersection designs. This research intends to answer the following questions: (1) How the operational performances may vary between conventional intersections and superstreets in human-driven vehicles. (2) How CAVs perform in different traffic conditions. (3) At what market penetration rate do the CAVs start to improve the traffic efficiency. (4) How the performances of CAVs may differ when CAVs are enabled with different levels of capabilities. By answering the questions above, this research can provide a better understanding of the performance of CAVs at innovative intersections since many innovative intersections share similar design features such as displaced left turns and channelized right of way.