Critical analysis of methods for assessing the safety of regulated and unregulated intersections, taking into account the complexity of transport interactions

Abstract

A critical analysis of classical and modern methods for assessing the safety of regulated and unregulated intersections, accounting for the complexity of traffic interactions, has been conducted. It has been shown that approaches based solely on accident statistics or the counting of conflict points have limited capacity to identify potentially dangerous situations and do not sufficiently account for interactions involving vulnerable road users — pedestrians, cyclists, and public transport users.

Based on a synthesis of research, the feasibility of moving from rigidly fixed empirical coefficients to a universal principle for forming weight indicators for conflict points is justified. A generalized approach to determining weighting coefficients for conflict interactions is proposed, combining the nature of transport interaction and the level of vulnerability of the most vulnerable participant in the conflict.

A universal formula for an integral indicator of intersection complexity has been developed, allowing the quantitative consideration of various types of conflict interactions, including those involving pedestrians, cyclists, and urban rail transport, without introducing a large number of separate empirical coefficients. The proposed indicator is interpreted as a measure of the potential danger at an intersection, consistent with the concept of surrogate safety analysis.

A typical urban, unregulated intersection demonstrates that accounting for conflicts involving vulnerable road users can significantly alter the final assessment of complexity and raise the intersection's potential danger category. This confirms the feasibility of the proposed approach for comparative assessment of alternative traffic management schemes and for prioritizing safety improvement measures.