The Grainger College of Engineering
Illinois Center for Transportation

New ICT-IDOT reports

4/14/2026 McCall Macomber

Illinois Center for Transportation is pleased to announce the publication of reports from the following Illinois Department of Transportation-sponsored projects, in order of publication.

R27-216: Optimizing the Use of Local Aggregate in Stone-Mastic Asphalt
Imad Al-Qadi, University of Illinois Urbana-Champaign
Brian Hill, Illinois Department of Transportation

The test site at ICT consists of six pavement sections made with different stone-matrix asphalt mixtures, tested with the Illinois Accelerated Pavement Tester.

Stone-matrix asphalt is a durable and stable hot-mix asphalt with a proven long service life. This project aimed to determine whether IDOT can use locally available aggregates in SMA to reduce the cost and environmental impact of its production without sacrificing resistance to pavement rutting or cracking.

The researchers determined rutting and cracking resistance by evaluating the results of SMA mixtures using local as well as traditionally imported aggregates. Reducing the cost of SMA may allow it to be used more widely in Illinois. Widespread use of SMA may result in less frequent pavement rehabilitation, fewer traffic interruptions from road construction and substantial cost savings.

R27-258: Evaluation of Digital Alert Systems Associated to Emergency Response Vehicles and Compliance with Move Over Law
Alireza Talebpour, University of Illinois Urbana-Champaign
Juan Pava, Illinois Department of Transportation

In 2021, 42,915 people were fatally injured in vehicle crashes, according to the National Highway Traffic Safety Administration, a 10.5% increase from 2020.
In 2021, 42,915 people were fatally injured in vehicle crashes, according to the National Highway Traffic Safety Administration, a 10.5% increase from 2020.

Digital alert systems broadcast the real-time presence of roadside hazards such as stopped emergency vehicles or roadway maintenance.

This project evaluated drivers’ responses to visual and auditory digital alert systems. Researchers measured the effects of digital alert systems on compliance with the Move Over Law as well as mobility and safety.

Measuring the benefits of digital alert systems will allow stakeholders to increase the use of the technology, increasing safety and improving mobility.

R27-194: Spatial and Temporal Load Distribution in Steel Bridge Superstructures (Vol. I): Agency Survey and Preliminary Numerical Modeling of Skewed Steel I-Girder Bridges for Field Instrumentation
Larry Fahnestock and James LaFave, University of Illinois Urbana-Champaign
Mark Shaffer, Illinois Department of Transportation

Provided by Larry Fahnestock. University of Illinois Urbana-Champaign graduate students Sunny Zhou and Gaoyu Liu install strain gauges on X-shaped cross frames at Mattis Avenue Bridge over I-57 in Champaign, Illinois, on Nov. 9, 2020.

This project investigates demands, load distribution, and static and dynamic responses of composite steel skewed I-girder bridge superstructures during construction and after bridges are in service.

This report documented the initial phases of the research: a survey to understand practices used and challenges faced by state transportation agencies when designing and constructing skewed steel I-girder bridges, information about and field instrumentation of two monitored bridges, methods for 3D finite element analysis, and preliminary analysis conducted to guide field instrumentation planning of the bridges.