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Mid-America Transportation Center

Evaluation of the Driveway Assistance Device (DAD) Sytems in One-Lane Two-Way Work Zones


University of Nebraska-Lincoln

Principal Investigator
Ernest Tufuor
PI Contact Information
Funding Source(s) and Amounts Provided
USDOT: $128,149
NDOT: $129,867
Total Project Cost
$ 258,016
Agency ID or Contract Number
Start Date
End Date
Research Objective
The objectives of this research are to: 1) determine the DAD display design that best directs drivers to safely enter the one-lane, two-way work zone operation and proceed in the proper direction of travel; 2) model efficacy of the DAD systems in terms of driver’s compliance or violation behaviors, as well as the time savings for both driveway and the main road traffic; and 3) develop a NDOT implementation guide outlining best practice for using these systems in Nebraska. At present, DAD systems are not included in the Manual on Uniform Traffic Control Devices (MUTCD). As part of the technology transfer component, this project will develop the necessary background material to have the MUTCD approve the use of DAD systems in work zones.
Potential Benefits
There are four main benefits: 1) The functionality of the DAD systems will be validated using empirical data. The performance of the DAD systems as measured by waiting time and driver’s compliance will be quantified. 2) Any potential modifications and improvements will be identified. 3) The validation of the benefit/cost procedure for the DAD system deployment will help refine the criteria used to justify and determine when DAD systems should be used in work zones. 4) The results of the study will be used to update the MUTCD to include DAD usage.
Brief Description of Research Project
When one lane of a two-lane, two-way roadway is closed as a result of a work zone, traffic in each direction will take turns utilizing the one lane that is open. This proposal will focus on the driveway assistance device (DAD) systems that are located in the one-lane two-way work zone. The proposed study will evaluate DAD systems in Nebraska. Their safety and efficacy will be analyzed quantitative, empirical performance measures including waiting times, compliance rates, and stop locations. It is anticipated that driver survey will also be conducted.
Describe Implementation of Research Outcomes
Impacts/Benefits of Implementation
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Modal Orientation
  • Safety and Human Performance