subscribe to ENR magazine subscribe
contact us
advertise
careers industry jobs
events events
FAQ
Mcgraw Hill Construction
ENR Logo
SUBSCRIBE TODAY
& receive immediate web access
comment

Hybrid Composite Beam is A Labor of Love for Designer

Text size: A A

How often did John R. Hillman, founder and president of Chicago-based HC Bridge Co., LLC, think about giving up on getting the industry to accept his hybrid bridge beam of concrete and steel with fiber-reinforced polymer materials? “Only about once a week,” he laughs.

Hybrids may be best solution when strong, shallow and lighter beams are needed.
Photo: John R. Hillman
Hybrids may be best solution when strong, shallow and lighter beams are needed.
----- Advertising -----

Hillman invented the beam design in 1996 after wondering what would happen if he combined concrete and steel with a composite material. Exposure to FRPs in graduate school at Virginia Tech and the experience of working with renowned bridge designer Jean Muller inspired him to marry the “age-old technology” of the arch structure with modern-day materials. “It became a mild obsession,” he says.

Riding the train to his daily job as an engineer at Teng & Associates, Chicago, Hillman did what engineers do—scribble down calculations. The result: a glass-fiber-reinforced shell, self-consolidating concrete for compression reinforcement, and high-strength continuous steel fibers for tension reinforcement. His first chance to prove the technology came in 2002, when Lehigh University engineering professor Dennis Mertz urged him to apply for a research grant from the Federal Railroad Administration and the state departments of transportation through the Transportation Research Board’s National Cooperative Highway Research Program.

“The hybrid composite beam is unquestionably unique,” says Neil Hawks, TRB staff representative. “Although the beam conforms to the principles of structural engineering, its ingenious combination of complex and commonplace materials yields a structural member that is lightweight and less bulky than its reinforced-concrete equivalent. With our current concerns about renewing our rail and highway bridges while minimizing disruption, these properties are in high demand.”

With the grant, Hillman successfully tested a 30-ft-long, 17-ft-wide span comprising eight beams in Pueblo, Colo., in 2008. It supported a full-size locomotive pulling 26 heavy-axle-load coal cars. “The hybrid composite beam will be the best solution for the many situations where stronger but shallower and lighter beams are needed,” notes Hawks.

John R. Hillman

Bridge engineer created a hybrid of conventional materials and composites that can create long-lasting, noncorrosive bridges that carry heavy loads.

The beam is catching on. The second application was the $2-million, 57-ft-long High Road Bridge in Lockport Township, Ill. This year, the New Jersey Dept. of Transportation used federal research funds to apply the beams on a $1.34-million replacement of state Rte. 23 Peckman’s Brook Bridge in Cedar Grove. Coming next is the Knickerbocker Bridge in Boothbay, Maine, an eight-span, 540-ft-long, $6-million replacement structure.

“It’s a labor of love to keep moving with this,” says Hillman of developing his patented technology. “Every time I did a major test, part of me hoped for a failure so I could move on. Then it would succeed, so I couldn’t stop.” Moreover, his colleagues at Teng gave him moral and engineering support. “Colleagues who I deem smarter than I—they told me it’s a great idea. So I couldn’t walk away from it,” he says.

----- Advertising -----
  Blogs: ENR Staff   Blogs: Other Voices  
Critical Path: ENR's editors and bloggers deliver their insights, opinions, cool-headed analysis and hot-headed rantings
Project Leads/Pulse

Gives readers a glimpse of who is planning and constructing some of the largest projects throughout the U.S. Much information for pulse is derived from McGraw-Hill Construction Dodge.

For more information on a project in Pulse that has a DR#, or for general information on Dodge products and services, please visit our Website at www.dodge.construction.com.

Information is provided on construction projects in following stages in each issue of ENR: Planning, Contracts/Bids/Proposals and Bid/Proposal Dates.

View all Project Leads/Pulse »

 Reader Comments:

Sign in to Comment

To write a comment about this story, please sign in. If this is your first time commenting on this site, you will be required to fill out a brief registration form. Your public username will be the beginning of the email address that you enter into the form (everything before the @ symbol). Other than that, none of the information that you enter will be publically displayed.

We welcome comments from all points of view. Off-topic or abusive comments, however, will be removed at the editors’ discretion.