Accelerating Roundabout Implementation in the United States: Volume I of VII - Evaluation of Rectangular Rapid-Flashing Beacons (RRFB) at Multilane Roundabouts

This volume is first in a series of seven. The other volumes in the series are: Volume II – Assessment of Roundabout Capacity Models for the Highway Capacity Manual, Volume III – Assessment of the Environmental Characteristics of Roundabouts, Volume IV – A Review of Fatal and Severe Injury Crashes at Roundabouts, Volume V – Evaluation of Geometric Parameters that Affect Truck Maneuvering and Stability, Volume VI – Investigation of Crosswalk Design and Driver Behaviors, and Volume VII – Human Factor Assessment of Traffic Control Device Effectiveness. These reports document a Federal Highway Administration (FHWA) project to investigate and evaluate several important aspects of roundabout design and operation for the purpose of providing practitioners with better information, leading to more widespread and routine implementation of higher quality roundabouts. This report presents results from a pedestrian accessibility study evaluating the effectiveness of Rectangular Rapid Flashing Beacons (RRFB) at multilane roundabouts in the U.S. The document summarizes data collection and analysis performed at 12 approaches at 7 multilane roundabouts in 5 states. The study applied an Accessibility Audit to all test locations, including an indicator study of blind pedestrian decision-making, a naturalistic driver yielding study, a vehicle free-flow speed study, a geometry audit, and a 12-hour traffic volume assessment. The findings from this study indicate that within the range of observed RRFB installations there are some likely relationships between traffic flow characteristics (volume and speed) and the availability of crossing opportunities in the form of gaps or yields. There is also some indication that the geometric configuration of a roundabout impacts its accessibility, either directly through obstruction of sight and hearing, or indirectly by allowing greater vehicular speeds. Overall, the results of these studies support the idea that RRFB-equipped multilane roundabouts can be accessible, but the roundabout geometry, vehicle speeds, and driver behavior have a strong influence on the overall accessibility of a site.

  • Record URL:
  • Corporate Authors:

    North Carolina State University, Raleigh

    Institute for Transportation Research and Education
    Centennial Campus Box 8601
    Raleigh, NC  United States  27695-8601

    Accessible Design for the Blind

    3 Manila Street
    Asheville, NC  United States  28806

    Kittelson and Associates, Incorporated

    610 SW Alder Street, Suite 700
    Portland, OR  United States  97205

    Federal Highway Administration

    Office of Safety, 1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Authors:
    • Schroeder, B
    • Salamati, K
    • Rouphail, N
    • Findley, D
    • Hunter, E
    • Phillips, B
    • Barlow, J
    • Rodegerdts, L
  • Publication Date: 2015-9


  • English

Media Info

  • Media Type: Digital/other
  • Edition: Technical Report
  • Features: Appendices; Figures; Photos; References; Tables;
  • Pagination: 74p

Subject/Index Terms

Filing Info

  • Accession Number: 01741937
  • Record Type: Publication
  • Report/Paper Numbers: FHWA-SA-15-069, Report No. 11861 Task 2
  • Contract Numbers: DTFH61-10-D-00023-T-11002
  • Created Date: Jun 4 2020 2:30PM