Road Safety Management of Uncontrolled Access Points: Design Criteria and Insights into Risk Factors

This study provides a comprehensive approach to the management of uncontrolled accesses, namely, access points without traffic lights, stop signs, right-of-way, yield signs, or right-turn acceleration/deceleration lanes. These elements of the road network are often associated with several safety issues given the inadequate conditions and limitations regarding their location, design, and visibility. This paper provides new insights into the geometric and functional design of uncontrolled accesses and contributes to the area of safety management measures. The implementation of the approach to a selected case study allows for the description of the methodology and to find interesting results concerning the cause-effect relationship between geometry-related variables and accidental events. In particular, the study focuses attention on the key factors of the geometric and functional design of accesses: radius and width, with the aim of defining more adequate design criteria aimed at improving safety. Furthermore, several interesting considerations are drawn relating to the types of connection transition shapes, allowing the selection of the most dangerous type for the safety of drivers and pedestrians. The most important finding is the high risk correlated to an access point with no materialised elements guiding the entry manoeuvre.