UNIVERSITY OF RUSE "ANGEL KANCHEV"
UNION OF SCIENTISTS - RUSE

Proceedings 2025
Faculty of Automotive and Transport EngineeringBook 4.2 · Sustainable and Intelligent Transport Systems, Technologies and Logistics

FRI-20.21-1-SITSTL-07

INFLUENCE OF THE DIAMETER OF ROUNDABOUTS ON THE SPEED OF MOVEMENT

Language: BGPages: 55-62

Cite this paper

Assoc. Prof. Toncho Balbuzanov, PhD

Department of Transport University of Ruse “Angel Kanchev”

ORCID: 0009-0008-7261-2299

E-mail: tbalbuzanov@uni-ruse.bg

Antonii Todorov, PhD Student

Department of Transport University of Ruse “Angel Kanchev”

E-mail: atodorov@uni-ruse.bg

Abstract

This study investigates vehicle dynamics within three roundabouts located in the city of Ruse, Bulgaria, by conducting field experiments using a specialized vehicle equipped with instrumentation for recording speed and g-force values during motion. The aim was to determine the typical speeds at which drivers navigate these intersections and to analyze how roundabout geometry influences driving behavior. The investigated roundabouts differ in size: 60 m, 80 m, and 100 m in diameter. The measured average speeds were 26.32 km/h, 29.74 km/h, and 33.99 km/h, respectively. The results indicate a clear correlation between the roundabout diameter and the average driving speed-larger roundabouts tend to permit higher speeds. These findings are relevant for traffic engineering, particularly in the context of urban planning, road safety assessments, and future roundabout design.

Keywords

roundabout, road safety, traffic behavior

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