Simulator and field study of effectiveness of speed management methods in work zone in Missouri

Abstract

[EMBARGOED UNTIL 12/1/2023] The objective of this research is to examine the effectiveness of six speed countermeasures in reducing vehicle speeds in work zones. Speed countermeasures such as law enforcement (active and passive), speed trailer displaying speed (with and without flashing speed or red and blue lights when above the speed limit), and work vehicle with red and blue lights were evaluated to assess their effectiveness in reducing vehicle speeds in the field and simulator study. Speed data were captured and analyzed at various westbound I-270 work zone locations in the field and from a simulator study. The simulator study also incorporated eye tracking devices to obtain driver behavior measures. In the 4-week field study, law enforcement speed countermeasures (active and passive) were found to be most effective in reducing vehicle speeds in work zones. The simulator study showed that the super law enforcement (active law enforcement and speed 11 trailer combination) was most effective in reducing vehicle speeds during daytime. Generally, the effect of speed reduction by speed countermeasures dissipated more quickly during nighttime than daytime. The simulator study also found that super law enforcement and speed trailer-related countermeasures had better visibility. Post-simulator and driver survey indicated that law enforcement would be the most effective in causing respondents slow down. Overall, the study showed that all evaluated speed countermeasures were effective in reducing vehicle speeds during daytime and nighttime, however, law enforcement speed countermeasures were found to have the greatest speed reductions.