Impact of intersection geometry and signage on pedestrian safety for vulnerable users: Analysis using microsimulation, SSAM and VIDA Irap

Abstract

Pedestrian safety is a critical issue affecting all citizens, especially in urban environments where the interaction between vehicles and pedestrians is constant. One of the major factors contributing to pedestrian insecurity are risky behaviors, which are often performed without thinking about the consequences. Crossing the street while distracted, not respecting traffic signals, walking in the road, or crossing the street in unauthorized places are common practices that increase the probability of accidents. Imprudent pedestrian habits generate unnecessary risk for all road users. Specifically, the analyzed intersection, characterized by high pedestrian flow (proximity to a hospital and a school), presents an elevated risk and compromises the safe mobility of vulnerable users due to infrastructure deficiencies and signage. Four scenarios were evaluated to improve pedestrian safety at the critical intersection, starting with Case 1 (baseline) which represented the current configuration. This baseline scenario, characterized by basic pedestrian crossings and limited signage, generated the highest number of conflicts and the lowest safety level according to iRAP. Case 2 introduced specific traffic signal improvements and adjustments to pedestrian crossing times, achieving a slight reduction in conflicts. Subsequently, Case 3 reinforced these measures by incorporating physical infrastructure such as refuge islands, wider sidewalks, and improved visibility, reaching an intermediate safety level. Finally, Case 4 (optimal scenario) integrated an exhaustive combination of interventions to maximize safety. These measures included the addition of an extra pedestrian crossing, expanded refuge islands, reduced turning radius, exclusive lanes, and complete signage.