Roundabout Safety Benefits, Design Considerations and Safety Evaluation Techniques A Review

Main Article Content

Engr. Ahmad Batari
https://orcid.org/0000-0002-9812-2887
Dr. M. N. Ibrahim
https://orcid.org/0009-0000-6931-2991

Abstract

Roundabouts are increasingly replacing conventional signalized intersections due to their potential to enhance traffic safety and operational efficiency. This paper examines and reviews the safety benefits, design considerations, and evaluation methods for roundabouts. Studies consistently show significant reductions in crashes at roundabouts relative to other at-grade intersection control systems, particularly severe injury crashes, with reductions ranging from 37% to 88%. Roundabouts reduce conflict points, lower vehicle speeds, and improve safety for both motorized and vulnerable road users. The methodology for this paper involved a comprehensive review of literature on roundabout design and safety evaluation techniques. Data from global studies were analyzed to identify key design elements such as geometric layout, signage, and pedestrian provisions, which contribute to roundabout safety. Various safety evaluation methods, including crash data analysis, traffic conflict techniques, and surrogate safety measures, were also assessed for their effectiveness in evaluating roundabout performance. Findings indicate that proper geometric design, clear signage, and the use of innovative features like right-turn bypass lanes and roundabout metering systems can enhance safety and traffic flow. Based on these findings, the paper recommends integrating these design elements, prioritizing the safety of vulnerable users, and utilizing advanced safety evaluation techniques, including simulation modelling and intelligent transportation systems (ITS) to further optimize roundabout performance.

Keywords: Roundabouts, Roundabout Benefits, Design Considerations, Safety Evaluation Methods

Article Details

Batari, A., & Na'iya Ibrahim, M. (2024). Roundabout Safety Benefits, Design Considerations and Safety Evaluation Techniques: A Review. African Journal of Advances in Science and Technology Research, 16(1), 74-96. https://doi.org/10.62154/ajastr.2024.016.010357
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Copyright (c) 2024 Engr. Ahmad Batari, Dr. M. N. Ibrahim (Author)

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This work is licensed under a Creative Commons Attribution 4.0 International License.

Engr. Ahmad Batari, Department of Civil Engineering, Abubakar Tafawa Balewa University, Bauchi

PhD Student, Department of Civil Engineering, Bayero University, Kano and a Lecturer, Department of Civil Engineering, Abubakar Tafawa Balewa University Bauchi, Nigeria.

Dr. M. N. Ibrahim, Department of Civil Engineering, Bayero University, Kano

Reader, and Head, Department of Civil Engineering, Bayero University, Kano

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