Evaluating Pedestrians' Safety on Urban Intersections
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sustainability Article Evaluating Pedestrians’ Safety on Urban Intersections: A Visibility Analysis Keila González-Gómez * and María Castro Departamento de Ingeniería del Transporte, Territorio y Urbanismo, Universidad Politécnica de Madrid, 28040 Madrid, Spain; [email protected] * Correspondence: [email protected]; Tel.: +34-910-674-215 Received: 17 October 2019; Accepted: 21 November 2019; Published: 23 November 2019 Abstract: Overall visibility plays a key role in the safety of pedestrians. Despite its importance, verifying the right provisioning of sufficient available sight distances among pedestrians and vulnerable road users (VRUs) is not a prevalent practice. On top of that, the pursuit for more sustainable modes of transportation has promoted the establishment of different shared mobility services which are prone to increase walking and, thus, the number of pedestrians and other VRUs in urban settings. With the intention of verifying how car-centered designs perform for non-motorized users, a 3D procedure that evaluates the visibility of pedestrians and other users is presented and applied to specific cases in Madrid, Spain. The proposed solution employs virtual trajectories of pedestrians with mobility impairments and without them, cyclists, and personal transportation device riders. Their visibility was assessed around the functional area of urban intersections, including zones where possible jaywalking practices might occur. The evaluation was performed three-dimensionally, making use of LiDAR data, GIS tools, and 3D objects. Results show the impact of street furniture location on visibility, the distinctive influence of vegetation on the lines of sight of each observer, and how design parameters that were intended to improve motorized traffic could affect VRU. Keywords: vulnerable road users; urban intersections; sight distance; road safety; LiDAR models 1. Introduction Walking, cycling, and riding are fundamental to the expansion of sustainable transportation, either used alone or in combination with other types of motorized transport (public transit, private ownership, carsharing, ridesourcing, etc.) [1]. In that sense, the widely adopted tendency of increasing public transit provision and the proliferation of shared mobility services are likely to augment the need for walking and, thus, the number of pedestrians and other vulnerable road users (VRU) in the urban scene [2]. Different bikesharing, motosharing, and shareable electric scooter services have flooded many cities around the world, attracting new users, whether for fun or convenience, with different levels of riding or biking expertise. This trend has altered regular commuting and recreation routes, as well as created new ones [3]. These new users have to coexist with motorized traffic, and they all possess different decision and reaction times, capabilities, speeds, etc. To create safer environments for these dissimilar users, many road authorities have applied different road safety policies, such as speed reductions, traffic calming interventions, among others [4]. Data from Spain’s General Directorate of Traffic show that from 2008 to 2017 accidents with victims increased 3% in urban roads, while rural areas saw a decrease of 2%. Most accidents with victims occurred in urban settings, specifically in streets, with pedestrians constituting 51% of road deaths [5]. Globally, VRUs constitute more than half of the fatalities that occur in all road traffic accidents [6]. For many decades there have been several efforts, from different approaches and fields of knowledge, that aim at decreasing road traffic deaths [7]. 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