The Grainger College of Engineering
Illinois Center for Transportation

Maximizing safety, mobility for smart work zones

1/29/2024 McCall Macomber

In Illinois, 6,366 work zone crashes occurred in 2021, according to the Illinois Department of Transportation. Effectively and quickly communicating real-time travel information in work zones is essential to helping Illinois “Drive Zero Fatalities to a Reality.”

Key to getting ahead of potential problems are smart work zone systems, which use sensors to collect real-time data such as speed and traffic volume to communicate travel information to drivers as they approach work zones.

Three University of Illinois Urbana-Champaign Department of Civil and Environmental Engineering faculty members developed design guidelines for smart work zone systems in an IDOT and Illinois Center for Transportation project, “R27-246: Development of Design Guidance for Smart Work Zone Systems.”

Khaled El-Rayes serves as principal investigator and Ernest-John Ignacio and Yanfeng Ouyang are co-PIs. Juan Pava, IDOT’s safety program unit chief, also leads the effort.

“Smart work zone systems provide real-time roadway information to better inform motorists, reduce traffic congestion and improve safety for motorists and construction workers,” El-Rayes said.

“Despite the benefits of smart work zone systems, there is little guidance on standardizing their adoption and implementation to maximize safety and mobility,” he added.

Transportation agencies have used smart work zone systems, such as the variable message sign shown above, for more than 20 years. These systems provide real-time data to drivers to improve work zone safety and mobility.
Transportation agencies have used smart work zone systems, such as the variable message sign shown above, for more than 20 years. These systems provide real-time data to drivers to improve work zone safety and mobility.

Their goal is to improve safety and mobility in Illinois’ work zones by determining when smart work zone systems are needed, how to design them and how to ensure these systems are adequately operating.

The researchers gathered data by surveying transportation agencies’ use of smart work zone systems, such as their effectiveness in reducing crashes, delays and queue length as well as cost and challenges.

They developed a tool to assist agencies with determining when smart work zone systems are needed on different types of freeway projects based on their conditions and characteristics, such as work zone length, how many lanes should be closed, speed limit, and more.

The tool also generates a layout design based on the recommended smart work zone system.

User interface of the tool developed in the ICT-IDOT project. The tool provides a total score based on a set of scoring criteria of work zone factors. The tool then provides a summary of the layout and devices required for the smart work zone system.
User interface of the tool developed in the ICT-IDOT project. The tool provides a total score based on a set of scoring criteria of work zone factors. The tool then provides a summary of the layout and devices required for the smart work zone system.

“One of the greatest challenges is selecting the right work zone for smart work zone systems and to select the right SWZS for the work zone,” said Nathan Peck, IDOT work zone safety engineer.

“Benefits include higher quality of information to the traveling public resulting in increased safety and mobility through the work zones, the most significant of which would be an increase of advanced warning of traffic slowdowns ahead to avoid rear-end crashes, which are the highest frequency and severity in Illinois work zones,” he added. 

The tool and proposed guidelines developed by the researchers will allow agency personnel to better determine which projects can benefit from deploying the technology, increasing its cost-benefit.

“The resources created should allow plan designers to have a better understanding of the tools available and more consistently include them (smart work zone systems) in design plans,” Peck said.

“The public will likely see them more regularly in work zone areas and have better real-time feedback to road conditions and our (IDOT) expectations as they navigate in and around work zones,” he added.