U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590

Skip to content U.S. Department of Transportation/Federal Highway AdministrationU.S. Department of Transportation/Federal Highway Administration

Federal Highway Administration Research and Technology
Coordinating, Developing, and Delivering Highway Transportation Innovations



Research and Development (R&D) Project Sites

[Printer friendly]


Project Information
Project ID:   FHWA-PROJ-07-0020
Project Name:   Evaluation of Speed-Activated Displays on Curves
Project Status:   Completed
Start Date:  September 4, 2007
End Date:  March 30, 2013
Contact Information
Last Name:  Knoblauch
First Name:  Richard
Telephone:  202-493-3369
E-mail:  richard.knoblauch@dot.gov
Office:   Office of Safety Research and Development
Team:   Roadway Team [HRDS-10]
Program:   Turner-Fairbank Highway Research Center
Project detail
Roadmap/Focus area(s):   Speed Management
Project Description:   The objective of this research project is to evaluate the effectiveness of low-cost, speed-activated dynamic curve warning systems on speeding and safety on horizontal curves in rural roadways. Research is being conducted under a cooperative agreement with the Center for Transportation Research and Education, Iowa State University.
(1) Conduct a national demonstration project to assess the effectiveness of dynamic speed-activated feedback sign systems on reducing speeds and crashes on curves on two-lane rural roads.
(2) Provide traffic safety engineers with additional tools to more effectively manage speeds and decrease crashes on horizontal curves on rural highways.
Background Information:   An estimated 56 percent of run-off-road fatal crashes on curves are speed related. Driver error on horizontal curves is often due to inappropriate selection of speed and inability to maintain lane position. Higher crash rates are experienced on horizontal curves that require greater speed reductions, while curves requiring no speed reduction do not have significantly different mean crash rates from their preceding roadway tangents.
Product Type:   Research report
Test Methodology:   Before/After evaluation with control sites.
Other Information:   A total of 22 speed-activated curve warning signs have been installed in┬áseven States. Notes: Due to the late date for installation of speed activated signs in Texas, the project will need to be extended to June 2012. Responsibility as a Contracting Officer's Technical Representative (COTR) was transferred to Richard Knoblauch in June 2010.
Expected Benefits:   The expected benefit is the reduction in speed-related lane departure crashes on rural high speed roads.
Deliverables:   Report on long-term effectiveness of a dynamic speed-activated feedback sign on driver performance, including comparison of two different sign types.
FHWA Topics:   Safety--Speed Management
TRT Terms:   Safety
Rural Highways
Traffic Speed
FHWA Disciplines:   Safety
Subject Areas:   Safety and Human Factors


Federal Highway Administration | 1200 New Jersey Avenue, SE | Washington, DC 20590 | 202-366-4000
Turner-Fairbank Highway Research Center | 6300 Georgetown Pike | McLean, VA | 22101