Faculty of Automotive and Transport Engineering
Book 4.2 - Sustainable and Intelligent Transport Systems, Technologies and Logistics
FRI-20.21-1-SITSTL-21
A MODEL FOR RISK ASSESSMENT OF VULNERABLE ROAD USERS AND ITS APPLICABILITY IN URBAN ENVIRONMENTS
Abstract: This study proposes a quantitative framework for assessing risk among vulnerable road users in urban environments based on the concept of potential conflict events. Risk is defined as an aggregated, dimensionless indicator resulting from the interaction of traffic flow characteristics, infrastructure and environmental conditions, and human-related factors. The model adopts a multiplicative structure and integrates key parameters including traffic intensity and speed, exposure of vulnerable users, roadway and weather conditions, age-related physical and cognitive characteristics, and the level of education and awareness.
The framework is applied to a representative urban road segment in the city of Ruse (Bulgaria) and is employed for scenario-based analysis to evaluate the impact of education-related interventions on risk levels. The results reveal a pronounced nonlinear relationship between education and awareness levels and both the aggregated risk index and the expected number of conflict events. Notably, even moderate improvements in education and awareness lead to disproportionately large reductions in risk.
The proposed approach enables comparative evaluation of alternative safety scenarios and supports the prioritization of preventive measures in contexts where detailed accident statistics are limited. The model is conceptually aligned with the Vision Zero framework and facilitates the transition from reactive to proactive road safety management in medium-sized urban areas.
The framework is applied to a representative urban road segment in the city of Ruse (Bulgaria) and is employed for scenario-based analysis to evaluate the impact of education-related interventions on risk levels. The results reveal a pronounced nonlinear relationship between education and awareness levels and both the aggregated risk index and the expected number of conflict events. Notably, even moderate improvements in education and awareness lead to disproportionately large reductions in risk.
The proposed approach enables comparative evaluation of alternative safety scenarios and supports the prioritization of preventive measures in contexts where detailed accident statistics are limited. The model is conceptually aligned with the Vision Zero framework and facilitates the transition from reactive to proactive road safety management in medium-sized urban areas.
Keywords: Vulnerable road users, Risk assessment, Urban traffic, Pedestrian safety, Scenario analysis, Vision Zero
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