Studies have found that a major cause of work zone accidents is vehicles traveling at unsafe speeds. Traditionally, standard speed limit signs have been employed to regulate work zone speeds, but motorists tend to ignore signs. In this study a radar unit was attached to a changeable message sign (CMS). If the radar detected a vehicle traveling above a preset speed threshold, the CMS displayed the message 'You are speeding slow down'. This study evaluated the effectiveness of the CMS with radar in reducing work zone speeds. Also, the project determined if there were significant differences between the average speeds of different vehicle types after they were exposed to the CMS with radar. Speed, volume, and vehicle type data were collected for the entire traffic stream with automatic traffic counters. Also, speeding vehicles that triggered the warning message were monitored at the middle and end of the work zone to find out how much they slowed after seeing the message. CMS with radar is an effective means for controlling vehicle speeds in work zones. Speeders slow down significantly after being exposed to the warning message. Since there are no statistically significant differences between the speeds of different vehicle types, the CMS with radar should have the same effect on all traffic streams, regardless of the vehicle type composition. CMS with radar should have the same effect on all traffic streams, regardless of the vehicle type composition. CMS with radar appears to be an effective alternate form of speed control.
Controlling Vehicle Speeds in Work Zones: Effectiveness of Changeable Message Signs with Radar
1996
74 pages
Report
No indication
English
Transportation Safety , Road Transportation , Transportation , Transportation & Traffic Planning , Highway Engineering , Speed control , Changeable message signs , Radar , Construction sites , Effectiveness , Area traffic control , Vehicle types , Traffic control devices , Highway safety , Construction site traffic control , Speed reduction , Traffic control , Display systems , Speed signs , Traffic volume , Virginia
Transportation Research Record | 1998
|Portable Changeable Message Signs at Work Zones
NTIS | 1984
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