Effectiveness of Speed Management Methods in Work Zones

Author/Presenter: Brown, Henry; Edara, Praveen; Sun, Carlos; Zeng, Qingzhong; Qing, Zhu; Long, Suzanna; Engstrom, Slade; Patil, Shivraj
Abstract:

Management of speeds is a significant component of any strategy to reduce work zone crashes. The objective of this study is to investigate the effectiveness of speed management countermeasures, such as speed display trailer, speed display trailer with red and blue lights, work vehicle with red and blue lights, and active and passive law enforcement, in managing vehicle speeds in work zones. The research methodology includes a review of the existing literature, field study, simulator study, and driver survey. The field study was conducted at a work zone on I-270 in the St. Louis region. All speed countermeasures tested in the field study achieved speed reductions. Active law enforcement was the most effective speed countermeasure for both daytime and nighttime conditions. Thirteen scenarios were studied using a driving simulator. Combining a speed display trailer and active law enforcement was the most effective countermeasure for daytime conditions. Using a speed display trailer by itself was the most effective for nighttime conditions. While respondents to both the driver and post-simulator surveys generally preferred the speed display trailer, they also admitted that the presence of law enforcement would be the most effective in causing them to slow down. Overall, the results of the study indicate that any of the tested countermeasures would help reduce speeds in a work zone. In some instances, deploying multiple countermeasures at the same site was found to be the most effective speed reduction strategy.