Smart Work Zone Control and Performance Evaluation Based on Trajectory Data

Work zone control strategies, such as taper length and transverse rumble strips, have the potential to significantly impact traffic operations and safety. The performance of these strategies is often evaluated based on traffic throughput, time headway, speed, and travel time measured at multiple locations or over a segment. Such metrics do not provide sufficient details regarding individual drivers’ speed choices and lane-changing behaviors over the course of the entire work zone. To address this issue, this research utilizes ultrahigh-definition radar and thermal camera sensors to capture detailed driver behavior data. Specifically, the radar sensors provide individual vehicle speed profiles along the segment prior to a work zone, allowing us to study how drivers adjust speeds in response to various control strategies. From the thermal camera videos, last-minute lane-changing events at the beginning of lane closure taper are extracted, which are further correlated with work zone control settings. Two taper lengths, transverse rumble strips, portable changeable message sign, and flashing speed limit signs are field evaluated in this study. Both descriptive and regression analyses have been conducted. The results do not show consistent and statistically significant impacts of transverse rumble strips and taper length on approaching speed and vehicle merges. However, both flashing speed limit signs and portable changeable message signs can significantly encourage early merging and reduce approaching speed. Additionally, drivers tend to drive slower and merge later at nighttime than in daytime work zones.