NTL Record

Title Accelerating Roundabout Implementation in the United States - Volume I of VII: Evaluation of Rectangular Rapid-Flashing Beacons (RRFB) at Multilane Roundabouts
Record ID 74421
Personal Name
Creator
Schroeder, Bastian J.; Salamati, Katy; Rouphail, Nagui M.; Findley, Daniel; Hunter, Elizabeth; Phillips, Brian D.; Barlow, Janet; Rodegerdts, Lee A.
Personal Name
Contributor
Shaw, Jeffrey
Corporate Creator United States. Department of Transportation. Federal Highway Administration. Office of Safety
Corporate
Contributor
North Carolina State University. Institute for Transportation Research & Education; Kittelson & Associates, Inc
Publisher United States. Department of Transportation. Federal Highway Administration. Office of Safety
Publication Date 20150901
Language English
Abstract 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.
Rosap ID dot:49386
Rosap URL https://rosap.ntl.bts.gov/view/dot/49386
TRT Terms Roundabouts; Implementation; Flashing beacons; Multilane highways
Geographical
Coverage
United States
TRIS Online
Accession No
1741937
Contract Number DTFH61-10-D-00023-T-11002
Report Number FHWA-SA-15-069
Resource type Tech Report
URL https://ntlrepository.blob.core.windows.net/lib/74000/74400/74421/FHWA-SA-15-069.pdf
Format PDF
Database NTL Digital Repository