Impacts of freeway speed limit on operation speed of adjacent arterial roads

Abstract Speed limit is one of the essential factors associated with roadway safety. Spillover effect is the tendency of drivers to drive at a higher speed on relatively lower-speed non-freeway roadways after exiting higher-speed freeways. Speed studies were conducted on urban arterial roads with speed limits of 45 mph - all adjacent to freeways with speed limits of 55 mph and 70 mph. A comparison of speed differences between motorists who exited the freeway and those who were already driving on the arterial road was performed. Results showed that the mean speed and 85th percentile of passenger cars on arterials adjacent to 55 mph freeway were 47.3 and 51.1 mph, respectively, while the mean speed and 85th percentile of passenger cars on arterial adjacent to a higher speed 70 mph freeway were 49.5 and 53.4 mph, respectively. Differences in the mean speeds between vehicles exiting from freeways and vehicles already driving on the arterial road were observed at all four sites evaluated. This paper provides researchers, policymakers, and engineers with a better understanding of the effects of speed spillover on adjacent roads when determining whether to increase the speed limit on freeways.

[1]  Reginald R. Souleyrette,et al.  Evaluation of Iowa’s 70 mph Speed Limit – 2.5 Year Update , 2009 .

[2]  M L Matthews,et al.  A Field Study of the Effects of Drivers' Adaptation to Automobile Velocity , 1978, Human factors.

[3]  James K Hammitt,et al.  Safety Impacts of SUVs, Vans, and Pickup Trucks in Two‐Vehicle Crashes , 2003, Risk analysis : an official publication of the Society for Risk Analysis.

[4]  S. Washington,et al.  Statistical and Econometric Methods for Transportation Data Analysis , 2010 .

[5]  Edward J Smaglik,et al.  Driver Feedback on Monetary Penalty and Its Impact on Work Zone Speed , 2012 .

[6]  G. Denton.  The influence of adaptation on subjective velocity for an observer in simulated rectilinear motion. , 1976, Ergonomics.

[7]  Karim El-Basyouny,et al.  The Impact of Lowered Residential Speed Limits on Vehicle Speed Behavior , 2014 .

[8]  R. Houten,et al.  How does an increased freeway speed limit influence the frequency of crashes on adjacent roads? , 2020, Accident; analysis and prevention.

[9]  Fred L. Mannering,et al.  An empirical analysis of driver perceptions of the relationship between speed limits and safety , 2009 .

[10]  Michael Nieuwesteeg,et al.  Self-reported speed compliance and attitudes towards speeding in a representative sample of drivers in Australia. , 2017, Accident; analysis and prevention.

[11]  A K Lund,et al.  Changes in motor vehicle occupant fatalities after repeal of the national maximum speed limit. , 1999, Accident; analysis and prevention.

[12]  William C Taylor.  THE IMPACT OF RAISING THE SPEED LIMIT ON FREEWAYS IN MICHIGAN. , 2000 .

[13]  Steven M. Casey,et al.  Changes in speed and speed adaptation following increase in national maximum speed limit , 1992 .

[14]  J Tiffin,et al.  Distortion of drivers' estimates of automobile speed as a function of speed adaptation. , 1969, The Journal of applied psychology.

[15]  William R. McShane,et al.  A review of pedestrian safety models for urban areas in Low and Middle Income Countries , 2016 .

[16]  Rune Elvik,et al.  A restatement of the case for speed limits , 2010 .

[17]  Siamak Ardekani,et al.  A statistical comparison of traffic measurements from the moving versus stationary observer methods , 2015 .

[18]  Peter T. Savolainen,et al.  Evaluating Outcomes of Raising Speed Limits on High Speed Non- Freeways , 2015 .