UIUC's highway research: Paving the way for more than a century

The University of Illinois (UI) pavement engineering program dates back to 1906 when Carol C. (C.C.) Wiley (BS 04 MS 10 and faculty member from 1906-1952) pioneered highway engineering at Illinois. His successors joked that he “came with the automobile.”

During the past 100 years, as roads have changed from dirt, to gravel, to asphalt and concrete, engineers at UI have made lasting contributions to the world’s roadways.

UI’s work remains some of the most commonly referenced by pavement engineers. Today’s faculty, students, and the Illinois Center for Transportation (ICT) build on the UI pavement program’s rich history and have firmly established it as the most well-respected in the world.

Westergaard Pioneers Concrete Pavement Design

While completing his doctorate at UI, Harald Westergaard (PhD 1916 and faculty member from 1916-1936) developed the first theoretical basis for the design of concrete pavements. Westergaard’s mechanistic models have been used throughout the world to improve concrete analysis and design. His major consulting projects included Hoover Dam and the Panama Canal.

UI Collaborates on National Road Tests and Interstate System

UIUC Pavement Faculty in 1979: Standing: Sam Carpenter (L) Ernie Barenberg (R);Sitting, L to R: Michael Darter, David Boyce, Moreland Herrin, Marshall Thompson, Berry Dempsey, Lufti Raad.

Illinois is home to several early road tests, including the Bates Road Test and the AASHTO Road Test in Ottawa, the results of which led to great advances in concrete and flexible pavements because, for the first time, trucks of different weights and axel spacings were taken into account. The road tests introduced such concepts as the load equivalency factor and roughness and performance measures. Moreland Herrin (faculty member from 1958-1987) worked as the Assistant Materials Engineer for the AASHTO Road Test.

In the late 1950s, Illinois, led by Ellis Danner (faculty member from 1946-1973), established the Highway Engineering Technician Training Program, which was a first-of-its-kind summer program in the nation. Run similar to a boot camp, the program trained future highway engineers, and many of the participants helped build the segment of Interstate 74 that runs east of Champaign to Danville.

UI’s Ernest Barenberg (faculty member from 1960-1996) and Marshall Thompson (BS 60, MS 62, PhD 64 and faculty member from 1965-1996) were integral in developing the mechanistic-empirical design frameworks for pavements, which merged sophisticated modeling with prediction of performance after 20 years of traffic and weathering. This work is reflected in the Eisenhower Interstate System and in many agencies’ guidelines for the design and construction of flexible pavement systems. Barenberg and Thompson also conducted revolutionary work to stabilize clay soils with lime. UI’s worldwide impact became apparent when other countries began translating the lime stabilization work into their own languages.

UI Builds Its Reputation through Advanced Material Testing and State-of-the-Art Laboratories

Revolutionary work in testing asphalt mixes during the 1970s to quantify their limits and optimal thickness, led by Sam Carpenter (faculty member from 1976-2006), gave transportation agencies a better understanding of their own mixes and how to achieve ideal thickness, which resulted in fewer construction needs.

UI’s continued success in pavement and materials research has been a direct result of outstanding and innovative laboratory facilities. In 1993, Barry Dempsey (PhD 1969 and faculty member from 1969-1999) facilitated the transportation group’s laboratory relocation to the Advanced Transportation Research and Engineering Laboratory (ATREL) facility that sits on 47 acres of the former Chanute Air Force Base in Rantoul, just 15 miles north of the Illinois campus. ATREL includes 67,000 square feet of lab space for pavements, materials, and transportation operations testing and research. Dempsey served as the lab’s first director and used it as a catalyst for the UI to reach new levels in transportation research.

CEAT Established for UI’s Work on Airfield Pavements

The UI is also well known for its work on airfield pavements. In 1995, Dempsey established the UI’s Center of Excellence for Airport Technology (CEAT) first sponsored by the Federal Airport Association. The outcome of this safety and pavement research center has been beneficial to the FAA and trained numerous students who have moved on to jobs in airport engineering. Even as Director of CEAT and ATREL, Dempsey continued developing useful products to solve pavement problems such as the interlayer stress absorbing composite (ISAC) material that carries U.S. and foreign patents and has been used in numerous airport and highway pavement projects. Dempsey also pioneered the development of the Integrated Climate Model (ICM) that has been used extensively in research and design procedures.

UI faculty member Michael Darter (1973-2003) has also been at the center of many developments including the widely used Pavement Condition Index (PCI) system, which was one of the first tools used to assess the condition of an airport pavement or roadway for future maintenance planning. His work led to the introduction of pavement management systems, which agencies use to inventory, maintain, and repair their pavement systems. He was also the lead investigator on the AASHTO M-E design guide for concrete pavements.

ATLAS Arrives at UI

In 2001, UI faculty specifically designed a loading system to conduct full-scale pavement testing for trucks, planes, and railcars. The Advanced Transportation Loading Assembly (ATLAS) provides the UI with unique testing abilities and can apply up to 6,000 repetitions per day and simulate up to 20 years of wear on pavement in a just a few weeks.

ICT Solidifies UI as Worldwide Leader in Transportation Research

In 2004, Imad Al-Qadi joined the faculty at UIUC. Al-Qadi further expanded ATREL’s capabilities, and in 2005, served as Founding Director for the Illinois Center for Transportation (ICT), which was established with the majority of its funding from the Illinois Department of Transportation and further strengthened the UI-IDOT relationship.

Since its inception, the ICT has grown tremendously to become one of the leading transportation centers in the nation. The center started with 12 projects, nine of which were pavement projects, and all the investigators were from the UIUC transportation group. Today, ICT has more than 145 approved projects involving more than 90 investigators from 12 universities that represent true diversity in transportation research. The ICT research of the past five years has helped support more than 135 young, talented graduate students, in addition to many undergraduate students, and these numbers are ever-increasing.

The UI pavement program has long attracted and educated the best students in the world, who then take jobs around the world, further spreading UI’s influence and reputation. Additional current faculty specializing in pavements include William Buttlar, Jeff Roesler, and Erol Tutumluer. Their contributions continue to improve pavements worldwide.

UI receives support from the Illinois Department of Transportation (IDOT), the Federal Highway Administration (FHWA), the Transportation Research Board, National Science Foundation, National Cooperative Highway Research Program, the Air Force, Federal Aviation Administration, industry, and many other sponsors. UI is considered the world leader in pavement science and engineering and taking leads on major national efforts related to pavement sustainability, modeling, and loading impact.  Building on the rich history of UI’s pavement engineering program, the ICT will continue to conduct groundbreaking transportation research to serve the state of Illinois, the nation, and the world.