Researchers
Patrick McCoy
About the research
The ADAPTIR is a portable, condition-responsive work zone traffic control system which is capable of providing drivers with real-time information about work zone traffic conditions via VMS and highway advisory radio (HAR). It was deployed in a work zone on I-80 between Lincoln and Omaha during the summer of 1999. The system is intended to provide warning to drivers of slower speeds and delays within the work zone, and encourage them to use caution and take alternate routes if possible. Various measures of effectiveness were employed to characterize the effect of the system on traffic and driver decisions. Traffic speed and lane distribution on the approach to the work zone were measured before and after the deployment of the ADAPTIR. The number of forced merges were obtained from video footage near the taper. Speeds were compared with advisory speeds to determine compliance. Diversion point volumes were logged to determine if drivers took alternate routes because of the system. Finally, a driver survey was conducted. Crash data was also examined, using a regression technique to compare crashes with and without the system. The systems use did not significantly affect any of the parameters with the exception of speed. The speed advisory message did have a effect on speeds, and the effect was stronger for signs located closer to the work zone.
Vendor: Scientex Corp.