Influence of cycling infrastructures on driver-cyclist interactions on urban roads: evidence from a driving simulator study

Abstract

The increasing modal share of cycling in urban environments has led to growing demands for safe, space-efficient, and cost-effective cycling infrastructure, especially on urban roads. These roads often lack adequate space for physically separated facilities, presenting challenges for traffic planners. This study examines the impact of four distinct cycling infrastructure designs, no cycling infrastructure (i.e., the reference scenario), advisory cycle lanes, cycle streets, and adjacent cycle lanes, on the interaction between cyclists and drivers on both one-way and two-way streets, with and without oncoming traffic, with one and two cyclists. Utilizing a driving simu-lator, this study investigates driver behavior during overtaking maneuvers, with cyclists represented as simulated agents under controlled experimental conditions. Despite widespread implementation of non-segregated cycling infrastructure on urban roads, there remains limited controlled, comparative evidence on how these designs influence driver overtaking behavior across different traffic and cyclist configurations. Key behavioral parameters, including lateral passing distance, passing speed, overtaking distance, and overtaking time, were analyzed under varying traffic and cyclist conditions. The results reveal that adjacent cycle lanes offer the highest safety margins on one-way roads. On the other hand, cycle streets provide the safest interactions on two-way roads, despite some drivers failing to adhere to overtaking restrictions. In addition, advisory cycle lanes are also identified as a space- and cost-efficient intervention. These findings provide actionable insights for policymakers and urban mobility planners to enhance cyclist safety on constrained urban road networks, while considering the behavioral tendencies of drivers and infrastructural limitations.