Investigation of tools, processes, and methodologies for facilitating the safe accommodation of vulnerable road users at freeway interchanges

Active transportation modes such as cycling and walking play a critical role in contemporary transportation systems by offering a healthy and environmentally friendly alternative to motorized travel. As both cyclists and pedestrians are among the most vulnerable roadway users, prioritizing their safety is paramount. Most initiatives and research on accommodating these vulnerable road users (VRUs) have focused on urban intersections, with less guidance being available for interchange ramps, which are high-speed, free-flow environments, typically with uncontrolled conflict points that pose distinct risks to VRUs. This study demonstrates tools, processes, and methodologies that have the potential to evaluate interchange alternatives to help give clearer guidance for safely accommodating VRUs through interchange environments. Microsimulation, a design flag assessment, and a safe systems index methodology were identified, and are demonstrated with Ontario, Canada case studies, as tools capable of facilitating the safe accommodation of VRUs at interchanges.