Prioritize Dynamic Speed Feedback Sign Deployment in Long-Distance and Long-Duration Work Zones to Reduce Speeding and Improve Driver Compliance.
A Field Study on I-65 Work Zone Compared Vehicle Trajectories Across Three Speed Management Strategies.
Robertson County, Tennessee
Strategies for Improved Driver Behavior within Work Zones
Summary Information
Speeding within freeway work zones poses safety risk to both workers and motorists. Although traditional enforcement measures such as police patrols can help manage speeding, continuous enforcement in WZs is often impractical, labor-intensive, or cost-prohibitive. This study evaluated driver speed behavior and compliance on a freeway work zone under three different speed management strategies: 1) Dynamic Speed Feedback Signs (DSFS), 2) Speed Wizard (SW), and 3) combinations of Speed Wizard with Portable Changeable Message Signs (PCMS). The field evaluation was conducted in 2023 on I-65 southbound in Robertson County, Tennessee, over approximately two and a half months using vehicle trajectory data extracted from high-resolution video collected by five solar-powered cameras placed along the corridor. The results indicated that DSFS and SW were the most effective interventions among those tested, leading to reductions in mean speeds and reducing severe speeding violations by at least eight percent.
This study identified several lessons learned, including:
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Prioritize DSFS deployment in long-distance and long-duration work zones to reduce speeding and improve driver compliance. The study found that DSFS consistently produced the largest reductions in both direct and indirect speeding effects in work zones. Deploying DSFS in high-speed and high-volume corridors, particularly in taper and activity areas can help maximize compliance and reduce crash risks.
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Avoid excessive information layering in work zones to reduce driver cognitive overload. The evaluation showed that combining SW systems with PCMS reduced overall treatment effectiveness. Concise and uniform messaging strategies are more effective for maintaining driver attention and minimizing desensitization.
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Implement lane-specific monitoring and enforcement strategies to reduce aggressive driving behaviors. The study identified left-lane traffic as more prone to higher-order speeding violations in work zones. Lane-specific radar monitoring and automated enforcement technologies can better target aggressive driving patterns.
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Adopt context-aware enforcement policies that incorporate weather and temporal conditions. The research found that speeding behavior varied significantly during weekends and under changing environmental conditions and recommended integrating real-time traffic, lighting, and weather data into enforcement scheduling to improve resource allocation and safety outcomes.
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Integrate spatial analytics into work zone safety evaluations to measure direct and spillover effects. The use of spatial econometric models in post-implementation assessments of work zone safety treatments can provide a more comprehensive understanding of feedback treatment effectiveness.
