Evaluation of Strategies to Manage Speed in Highway Work Zones

Safety in reconstruction and maintenance work zones continues to be the primary concern of transportation engineers. Speeding is one of the major contributors of work zone crashes. To decrease the occurrence of potential speeding-related crashes, the Wisconsin Department of Transportation (WisDOT) is seeking effective methods of controlling speed at Wisconsin work zones to improve traffic safety. In an attempt to better understand how the speed control strategies impact work zone speed in Wisconsin, this study was designed to evaluate the performance of several speed control strategies and identify the most effective strategies under specific work zone conditions. Speed control strategies including the use of dynamic speed display board and three enforcement methods were evaluated at Wisconsin long-term highway work zones located on State Trunk Highway (STH) 29 and STH 164, respectively. Compared with previous research, the study provides more insight into the long-term impact of these speed control strategies. The results show a promising outcome of using these strategies in Wisconsin work zones. Time of day, truck percentage, and free-flow speed affected the performance of speed control strategies in work zones. Further, a new approach was developed based on regression models to compare the effectiveness of speed control strategies under varying traffic conditions, and therefore, to assist engineers in selecting appropriate strategies.