KU Connection

Research group safeguards old bridges

The KU Fatigue and Fracture Research Group was extending the lives of steel bridges long before the shocking collapse in August of the Minneapolis I-35W Mississippi Bridge.

But in the wake of that deadly disaster, KU’s four-decades-long mission to make bridges safer has added urgency.

“We still don’t know what happened in Minneapolis,” said Stanley T. Rolfe, the A.P. Learned Distinguished Professor of Civil, Environmental and Architectural Engineering, who leads the group. “It took everyone by surprise. It’s a wake up call that we need to spend more time, effort and money on maintenance of older bridges.”

A recipient of the American Society for Testing Materials Fracture Mechanics Medal, Rolfe brings more than 40 years of research and national leadership to the subject of bridge integrity. He also has co-authored a classic textbook, Fatigue and Fracture Control in Structures, now in its third printing.

Rolfe heads a team of engineering faculty at KU composed of professors Ron Barrett-Gonzalez, Caroline Bennett and Adolfo Matamoros, that works with outside engineers such as the Kansas Department of Transportation (KDOT) and Kansas City, Mo.-based architectural firm HNTB Corp. Using computer simulations, field instrumentation, lab tests and analysis of high-performance materials, the group’s cutting-edge research drives toward improved understanding of steel bridges’ resistance and reaction to fatigue and fracture.

The Fatigue and Fracture Research Group also has saved the taxpayers of Kansas millions of dollars. Working with KDOT, the KU group has helped to safely extend the viability of older bridges that otherwise would be replaced with new multimillion-dollar spans. The latest example is the Tuttle Creek Bridge on K-16 near Manhattan. After the 5,350-foot-long steel structure developed fatigue cracks, the group analyzed the bridge and suggested repair methods and retrofits. To date, the bridge has not developed new cracks and is estimated to have 100 more years of useful life.

“You talk about getting big benefits from research,” said Kenneth Hurst, engineering manager of the State Bridge Office at KDOT. “We’ve been working with KU and Stan Rolfe for quite some time on fracture and fatigue issues. The Tuttle Creek Bridge was sort of a culmination where we verified the retrofitting on KU’s computers and validated it in the field by actually doing the testing. We’re very proud of this particular job.”