The Grainger College of Engineering
Illinois Center for Transportation

New ICT-IDOT reports

1/18/2025 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-SP71: Advancing our Understanding of Self-Enforcing Streets and the Use of Target Speeds to Improve Safety
Alireza Talebpour, University of Illinois Urbana-Champaign
Stephane Seck-Birhame, Illinois Department of Transportation
Victoria Barrett, Chicago Metropolitan Agency for Planning

Speeding is a major contributor to crashes, with over 12,330 people fatally injured in crashes in 2021, according to the National Highway Traffic Safety Administration.
Speeding is a major contributor to crashes, with over 12,330 people fatally injured in crashes in 2021, according to the National Highway Traffic Safety Administration.

Designing “self-enforcing streets” is one way to increase safety by better informing drivers of safe driving speeds through physical design and informational features.

The aim of this project was to improve our understanding of self-enforcing streets and identify opportunities and barriers to their implementation as future areas of research and needs. Researchers reviewed the state of the practice and research for self-enforcing streets in the U.S. and abroad.

Better leveraging design to increase speed limit compliance will improve traffic safety by reducing traffic fatalities and serious injuries.

R27-205: Development of Bridge Load Testing Program for Load Rating of Concrete Bridges
Bassem Andrawes, University of Illinois Urbana-Champaign
Ruben Boehler, Illinois Department of Transportation

All bridges must undergo regular inspection and load rating, which determines the weight a bridge can safely support.
All bridges must undergo regular inspection and load rating, which determines the weight a bridge can safely support.

A bridge’s load rating factor determines if the bridge should be closed to traffic or if the weight placed on it should be restricted.

The goal of this project was to develop a method for IDOT to perform diagnostic and proof load testing of concrete slab bridges. The developed method will allow structural engineers to evaluate the load capacity of concrete slab bridges more accurately.

Effective use of the developed method will result in fewer bridges being unnecessarily restricted from traffic.

R27-225: Report on Agency Survey and National Bridge Inventory Analysis for Damaged Steel Girders
Larry Fahnestock, Ahmed Elbanna, and James LaFave, University of Illinois Urbana-Champaign
Spencer Koehler, Illinois Department of Transportation

Most states report having between 2,000 to 16,000 bridges, and an average of 3.96% of those bridges are low-clearance bridges, according to a survey conducted by researchers in the ICT-IDOT study.
Most states report having between 2,000 to 16,000 bridges, and an average of 3.96% of those bridges are low-clearance bridges, according to a survey conducted by researchers in the ICT-IDOT study.

Bridge strikes — events where over-height vehicles impact bridge superstructures — are common across the U.S. and pose significant challenges for bridge owners.

Researchers surveyed state highway agencies on low-clearance bridges and bridge strikes as well as their inspection, analysis and repair practices for damaged girders.

The results can inform future research directions regarding steel girders damaged in bridge strikes, such as innovative methods for damage inspection, assessment and repair.

R27-245-HS: Quantification of the Effectiveness and External Noise of Rumble Strip Designs
Khaled El-Rayes, Ramez Hajj and E.J. Ignacio, University of Illinois Urbana-Champaign
Benjamin Sperry, Illinois Department of Transportation

Provided by E.J. Ignacio. A non-tapered sinusoidal rumple strip on an Illinois roadway. More than half of U.S. traffic fatalities occur after a driver crosses the edge or center line of a road, according to the Federal Highway Administration, which is why designing effective rumble strips is key to safer roadways.
Provided by E.J. Ignacio. A non-tapered sinusoidal rumple strip on an Illinois roadway. More than half of U.S. traffic fatalities occur after a driver crosses the edge or center line of a road, according to the Federal Highway Administration, which is why designing effective rumble strips is key to safer roadways.

Rumble strips — patches within a roadway that warn drivers when to slow down or when they are leaving their lane — can cause excessive noise to nearby neighborhoods. Here researchers investigated rumble strip designs that maximize safety while minimizing noise for nearby residents.

The research team will help IDOT “Drive Zero Fatalities to a Reality” by identifying rumble strip designs that ensure roadway safety while reducing external noise for Illinois residents and businesses.