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Pitt Lecture Features Pioneer in the Study of Bridge-Fatigue Damage, a Crucial Issue for Pittsburgh Spans

PITTSBURGH--Just as well known as Pittsburgh′s abundance of bridges is the fact that many of the city′s aged spans are crumbling and rusting under the stress of time and their own weight.

One reason for this decay is that many of Pittsburgh′s bridges were built before engineers fully understood the toll that age and fatigue can inflict on a bridge, as well as how to prevent it--or, in other words, before John W. Fisher began looking into these problems in the late 1960s.

Now a Professor Emeritus at Lehigh University, Fisher brings his noted expertise in bridge design to the University of Pittsburgh for the 2011 Landis-Epic Lecture hosted by the Swanson School of Engineering′s Department of Civil and Environmental Engineering. In his lecture, "Fatigue and Fracture: A Challenge for Existing and Future Steel Bridges," Fisher will examine the ongoing efforts to study and prevent fatigue-based damage, as well as building practices from the past that actually exacerbate bridge deterioration today. The lecture is free to the public and will be held at 4:30 p.m. March 17 in the Frick Fine Arts Auditorium, 650 Schenley Dr., Oakland. A reception will follow the lecture.

When Fisher began his work, fatigue was not considered the serious bridge-performance issue it is now. Limited, small-scale tests comprised the experimental knowledge of fatigue cracking, and certain building practices unwittingly encouraged fractures--for example, a rule adopted after World War II that avoided welding to tension flanges has resulted in extensive cracking and damage in bridges today.

Fisher was among the first researchers to conduct large-scale tests and accurately determine the stress range of bridge welds and components. (Pitt professor of civil and environmental engineering Kent Harries, one of the many engineers influenced by Fisher′s work, conducts related large-scale research.) Fisher′s work prompted the American Association of State Highway and Transportation Officials, which sets building standards for U.S. highways, to adopt codes related to fatigue in 1974. His basic data serves as the basis for bridge codes worldwide.

Fisher has published more than 300 articles, reports, and books in scientific and engineering journals. His numerous honors include his election to the National Academy of Engineering in 1986, the 1995 John A. Roebling Medal for lifetime achievement in bridge engineering, and the American Association of Engineering Societies′ 2000 John Fritz Medal, widely considered the highest and most prestigious award in the engineering profession. (Pitt engineering alumnus and trustee John A. Swanson [ENGR ′66], for whom the Swanson School is named, received the 2004 Fritz Medal and was elected to the National Academy of Engineering in 2009.)

The Landis-Epic Lectureship was established in 1991 in honor of Pitt civil engineering alumnus Donald H. Landis (ENGR ′52), president of Epic Metals Corporation and a nationally recognized leader in the design and construction of cold-formed steel structures.

Contact: Paul Kovach