A material contribution to bridge engineering

Alan W. Pense, provost emeritus and professor emeritus of materials science and engineering, was recently acknowledged for his outstanding contributions to bridge safety and repair.

At the 5th New York City Bridge Conference in August, Pense received the Bridge Engineering Association’s Bridge Engineering Research Award.

The focus of the conference was bridge safety and repair, including methods of improving current inspection and monitoring practices. The proceedings of the conference are being published in a volume titled Safety and Reliability of Bridge Structures.

Pense, an expert in the welding of iron and steel, was cited for his efforts to prevent bridge failures.

The award was completely unexpected, he said, but I’m glad to know they recognize the significant amount of work that still needs to be done with steel and bridges.

Pense joined the faculty in 1957 and received his Ph.D. from Lehigh in 1962. He was coauthor of the funding proposal that led to the establishment in 1986 of Lehigh’s ATLSS (Advanced Technology for Large Structural Systems) Center.

Researchers at ATLSS conduct cutting-edge research into the design and materials used in bridges and other large structures. They develop technologies that improve the performance of structures over the life cycle for which they are designed.

A Good Samaritan is born

Pense said it was his welding experience that initially caught the attention of his bridge-research colleagues at Lehigh. When other engineers needed an opinion on steel fatigue or on the welding of two steel plates, they asked Pense for advice. His expertise grew to include structural materials, forensic and failure analysis of fallen bridges, and the legal issues that accompany structural failures.

I fell in among bridge engineers, and I became their Good Samaritan, says Pense, who collaborates with Ben Yen and John Fisher, professors emeritus of structural engineering, to solve bridge issues and teach the next generation of bridge engineers.

Lehigh’s structural engineers, says Pense, were the first ones who got me to look under bridges. They put me in a snooper to examine the pins under an eyebar bridge, and I liked it—except for the time when a heavy fire truck drove overhead and caused the bottom of the bridge deck to hit me on the head.

Pense has gained renown for his work with stressed and fatigued bridges. He has inspected numerous cracked and failed bridges, including the Liberty Bridge and I-79 Bridge in Pittsburgh in 1979 and the second Silver Bridge in West Virginia in 1985. The original Silver Bridge collapsed in 1967, killing 40 people. Lehigh engineers conducted the forensic analysis of that failure.

A forensic specialist

Pense’s knowledge of the first Lehigh experience with the Silver Bridge allowed him to spot a similar problem with the pin connection on the Liberty Bridge, helping correct a problem that could have led to a comparable bridge collapse in Pittsburgh.

Pense also examined the fractured pieces of the gusset plates from the I-35W Bridge in Minneapolis that collapsed in 2007. Investigators concluded that the bridge failed because the gusset plates—steel pieces used to reduce stress on other structural elements—were undersized.

Currently, Pense is inspecting pieces of a wrought iron bridge dismantled in northern Pennsylvania. Authorities must decide whether to reuse or replace the bridge’s structural members, and Pense will help determine which route is safer.

Pense has extensive experience as an international consultant to private companies and government agencies, and this has led him to receive numerous other awards, including Lehigh’s Hillman Faculty Award in 1997.

Pense is an elected member of the National Academy of Engineering, one of the highest honors bestowed on engineers. He is a Fellow of the American Welding Society and also of the American Society Metals. He served as Lehigh’s provost and vice president for academic affairs from 1990 to 1997, and as dean of the engineering college, now the P.C. Rossin College of Engineering and Applied Science, from 1988 to 1990.