The Amish Sawmill Bridge is the first press-brake-formed steel tub girder bridge constructed in the U.S. Photo by SSSBA.

Innovative Press-Brake-Formed Steel Tub Girder System Featured in "Bridge Structures" Journal

August 3, 2020

WASHINGTON D.C. – An article highlighting a new technology developed by the Short Span Steel Bridge Alliance (SSSBA) and its industry partners has been published in a key bridge technology journal. The article, “Fatigue Performance of Singular and Modular Press-Brake-Formed Steel Tub Girders,” appeared in “Bridge Structures,” Volume 16, No. 1, which was published on July 9, 2020. It was authored by Karl Barth, Ph.D., the Jack H. Samples Distinguished Professor at West Virginia University, who headed the industry task group responsible for developing the technology; Greg Michaelson, Ph.D., P.E., associate professor at Marshall University, who was involved in the early research on the new technology; and Robert Tennant, Ph.D. engineering student at West Virginia University. Barth and Michaelson also provide expert assistance via the SSSBA’s Bridge Technology Center.

The article examines the modular testing of the press-brake-formed steel tub girder (PBTG) bridge system for short span structures of up to 60 feet. Specifically, it covers the scope of the testing, which includes:

  • Fatigue testing of singular composite girders simulating a 75-year life in a rural environment,
  • Evaluation of two slab edge treatment methods to determine the optimal option for the Ultra-High-Performance Concrete (UPHC) joint between modular tub girder units, and
  • Evaluation of the system’s fatigue performance by connecting longitudinally two composite modular press-brake-formed tub girders with a UHPC joint.   

The testing demonstrated that the press-brake-formed tub girders behaved adequately with respect to fatigue, as did the longitudinal joints composed of UHPC.

Dr. Barth stated: “We’ve come a long way since our team introduced the concept of the PBTG system in 2011. PBTG bridges are now in service in five states – Iowa, Ohio, Michigan, Texas and West Virginia. This system saves significant costs and time. It is a viable, economical solution to meeting the nation’s challenge to replace its aging bridge infrastructure, with the greatest need in the short span category of 140 feet or less.”

For more information or to purchase the article, visit “Bridge Structures” focuses on practical issues and how certain techniques can be adopted in the work of the bridge engineer. It also narrows the gap between researchers and practitioners and provides state-of-the-art solutions to challenges faced by bridge engineers.

The Short Span Steel Bridge Alliance (SSSBA) is a group of bridge and buried soil steel structure industry leaders who have joined together to provide educational information on the design and construction of short span steel bridges in installations up to 140 feet in length. For more news or information, visit or follow us on Twitter at @ShortSpanSteel or Facebook at   


Debbie Bennett
Senior Manager, Construction Communications
American Iron and Steel Institute
Tel: 202.452.7179

Dan Snyder
Short Span Steel Bridge Alliance
Tel: 301.367.6179