With vehicle miles traveled in Illinois nearly doubling from 52 billion in 1970 to 103 billion in 2023, the need for efficient and durable pavement designs has become crucial, writes McCall Macomber for the Illinois Center for Transporation. To address this growing demand, the Illinois Center for Transportation (ICT) and the Illinois Department of Transportation (IDOT) have partnered on a joint project titled “R27-230: Performance and Design of Continuously Reinforced Concrete Pavements (CRCP)“. Jeffery Roesler, CEE Ernest Barenberg Professor, and Charles Wienrank, IDOT’s pavement design engineer in the Bureau of Research, led the project. The project aims to update IDOT’s design approach for CRCP, which is primarily used on interstates with heavy truck traffic.
CRCP pavements use longitudinal steel reinforcing bars to hold together tightly spaced transverse cracks, providing a long-lasting solution with minimal maintenance. However, the high cost of CRCP, due to its increased use of steel, has limited its adoption. The project focuses on developing more economical designs while maintaining CRCP’s performance advantages. By revisiting the current design procedures, ICT and IDOT seek to make CRCP a more viable option for widespread use on Illinois roadways.
Researchers have employed a mechanistic-empirical method to predict pavement performance and are validating their models using data from real-world CRCP projects. By analyzing traffic growth and the current performance of CRCP sections, the team is refining the design process to ensure that future roadways can better withstand increased traffic levels. The updated design procedure is expected to extend the life of CRCP pavements without increasing concrete slab thickness, making the roads more cost-effective to build.
The project also evaluated the performance of existing CRCP overlays in Illinois using advanced pavement software. The findings revealed that the structural failures in these pavements were lower than predicted, demonstrating the potential to optimize CRCP designs further. This research will enable IDOT to construct more durable, high-performing roadways while managing costs, ultimately allowing the state to build more roads within the same budget constraints.
Read more here: https://ict.illinois.edu/news/newsletters/more-newsletters/november-2024/cast-in-concrete-designing-high-performing-economical-roadways