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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation
OFFICE OF RESEARCH, DEVELOPMENT, AND TECHNOLOGY AT THE TURNER-FAIRBANK HIGHWAY RESEARCH CENTER

Developing Crash Modification Factors for Mini‑Roundabouts

Publication Information

Publication Type:
Technical Report
Publication Number:
FHWA-HRT-23-019
Abstract:

The research documented in this report was conducted as part of the Federal Highway Administration’s (FHWA) Evaluation of Low-Cost Safety Improvements Pooled Fund Study (ELCSI-PFS). FHWA established this PFS in 2005 to conduct research on the effectiveness of safety improvements identified by the National Cooperative Highway Research Program (NCHRP) Report 500 guides as part of the implementation of the American Association of State Highway and Transportation Officials’ Strategic Highway Safety Plan. ELCSI-PFS studies provide a crash modification factor (CMF) and benefit–cost economic analysis for each targeted safety strategy identified as a priority by member States of the PFS.
 

This report documents the evaluated safety effectiveness of mini-roundabout (MR) installations at two-way stop-controlled (TWSC) and all-way stop-controlled (AWSC) locations. This study focused on MR safety effectiveness using data such as dimensions, number of lanes, median types and widths, and number of legs at various sites in Washington, Michigan, and Maryland. The analysis found a statistically significant crash reductions of 39 percent in multivehicle crashes at MRs converted from AWSC in all three States.


These study results may be of interest to roadway safety professionals, State and local engineers, and planners responsible for the design and operation of facilities that may benefit from MR installations.

 


 

Recommended citation: Federal Highway Administration, Developing Crash Modification Factors for Mini‑Roundabouts (Washington, DC: 2023) https://doi.org/10.21949/1521962

Publishing Date:
April 2023
Posting Date:
Digital Object Identifier:
https://doi.org/10.21949/1521962
Author(s):
Avelar, Raul (ORCID: 0000-0002-3962-1758)
Park, Eun Sug (ORCID: 0000-0001-6224-7007)
Kutela, Boniphace (ORCID: 0000-0002-5450-1623)
Publishing Office:
Safety Data and Analysis Team
FHWA Program(s):
Research
Safety
AMRP Program(s):
Improving Highway Safety for All Users
FHWA Activities:
Intersections
Pedestrian / Bicycle
Subject Area:
Research
Pedestrians and Bicyclists