Evaluation of Drivers' Compliance to Temporary Speed Limits while Approaching Work Zones on Two-Lane Highways

摘要

Speed is considered to be a critical factor in the cause of crashes in work zones. Temporary speed limits are posted in work zones to control driver's speeds and reduce the risks of casualties and create a safe environment for both the workers and the drivers. Previous researches show reduction in speeds in work zones, but these speed reductions are inconsistent throughout the work zone section. Low levels of speed limit compliance exist in the work zone because drivers still drive above the speed limit in most cases.;This study was conducted to evaluate the behavior of drivers concerning their level of compliance to the temporary speed limits signs as they approach and drive through two-lane work zones. Three two-lane highway work zones were selected for this study. The average speed and operating speed (85th percentile speed) was determined for each data collection location in the work zone. A pro-laser 4 Lidar speed gun was used to collect vehicle speed data in locations at the work zone before the Dynamic Message Sign (DMS) and after the DMS.;The results showed some reduction in speeds after the drivers passed the DMS, but in a comprehensive analysis of the vehicle speed data collected, there exists low levels of compliance to the speed limits in all the two-lane work zones examined. This is due to the insufficient measure put in place in the work zones to aid speed limit compliance.;The study of drivers' speed behavior in work zones should not majorly focus on multi-lane roads because of their high design standards and regulations. Small two-lane work zones should also be taken more into consideration because the compliance to the speed limit is low in such work zones, and crashes are liable to occur. The results of this study should be given a careful thought to improve on future geometric setup and traffic control decisions of these types of work zones.