Hazardous Bicycle Maneuvers at Single-Lane Roundabouts in Massachusetts: A Conflict and Events Study

Roundabouts have been known to relieve congestion, reduce travel times, and decrease accident rates. Studies indicate that despite reducing the total crash rate, roundabouts show a significant increase in the proportion of crashes that involve a cyclist. These crashes are primarily due to cyclists who create a bicycle lane through the roundabout. The purpose of this study is to determine if cyclist safety should be of particular concern in roundabouts in Massachusetts, specifically whether or not cyclists and/or vehicles are performing maneuvers outlined in previous studies to be major contributors for cyclist-based crashes. A custom conflict/event and compliance study was designed. Preliminary studies were performed at a roundabout located at the University of Massachusetts, Amherst. Subsequent studies were performed at various roundabout locations throughout Massachusetts. This study recorded all bicycle movements and any observed bicycle/vehicle interactions, tracking specific maneuvers that could create a hazardous or unsafe situation. The number of bicycles that performed unsafe maneuvers was compared to the total number of bicycles observed traversing the roundabout. This study confirms that some cyclists who use the roundabout at the University of Massachusetts Amherst operate in an unsafe manner or in a way defined to be a leading cause of accidents involving a bicycle in a roundabout (32% of all observed cyclists). Similar results were found at other roundabouts throughout Massachusetts (33% of all observed cyclists). Possible solutions were postulated.

• Supplemental Notes:
  • This paper was sponsored by TRB committee ANB75 Roundabouts.
• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Berthaume, Andrew
  • Knodler Jr, Michael A
• Conference:
  • Transportation Research Board 92nd Annual Meeting
  • Location: Washington DC, United States
  • Date: 2013-1-13 to 2013-1-17
• Date: 2013

Language

• English

Media Info

• Media Type: Digital/other
• Features: Figures; References; Tables;
• Pagination: 17p
• Monograph Title: TRB 92nd Annual Meeting Compendium of Papers

Subject/Index Terms

• TRT Terms: Bicycle crashes; Bicycle lanes; Cyclists; Roundabouts; Traffic conflicts
• Geographic Terms: Massachusetts
• Subject Areas: Pedestrians and Bicyclists; Safety and Human Factors; I83: Accidents and the Human Factor;

Filing Info

• Accession Number: 01477858
• Record Type: Publication
• Report/Paper Numbers: 13-4216
• Files: TRIS, TRB, ATRI
• Created Date: Apr 10 2013 12:18PM