International Journal of Transportation Engineering

International Journal of Transportation Engineering

Roundabout Capacity: Investigating the Impact of the Weaving Length and Entry/Exit Radii with AIMSUN

Document Type : Research Paper

Authors
1 School of Built Environment, Faculty of Engineering, Islamic Azad University Central Branch, Tehran, Iran
2 Department of Civil and Environmental Engineering, Tarbiat Modares University, Tehran, Iran
3 Department of Civil Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran
Abstract
Roundabouts are recognized as effective traffic management solutions, offering advantages such as improved safety and reduced congestion compared to signalized intersections. However, exceeding the roundabout's capacity can result in decreased efficiency and safety. The capacity of a roundabout depends on various factors, including traffic flow rates, geometric design parameters, and traffic flow characteristics. This study investigates the influence of weaving length, entry radius, and exit radius on the capacity of a roundabout in Sanandaj, utilizing AIMSUN traffic simulation software. Statistical and computational methods are applied to analyze data obtained from parameter analysis. The findings emphasize that imbalanced dimensions and a limited perspective in transportation network design contribute to traffic congestion. Consequently, comprehensive consideration of geometric and behavioral aspects of users within the transportation network is crucial when designing roundabouts. This analytics-driven study provides valuable insights and patterns, enabling the development of original content that surpasses existing research, ultimately facilitating the identification of areas for improvement and effective decision making.
Keywords

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