The first permanent highway installation of hybrid-composite beams (HCBs) was completed recently in Lockport Township, Ill. Crews finished the High Road Bridge over Long Run Creek three months ahead of schedule.
The original bridge, completed in 1935, was structurally deficient and functionally obsolete. To reduce further maintenance costs, the replacement structure utilized HCBs that provide extended service life with little or no maintenance.
HCBs are comprised of three main sub-components: an FRP shell, compression reinforcement, and tension reinforcement. The compression reinforcement consists of concrete that is pumped into an arch conduit within the beam shell. The tension reinforcement consists of high-strength steel prestressing strands that run along the bottom flanges of the beam shell. All of this is encapsulated in a fiber-reinforced plastic shell protecting the beam from salt corrosion and providing added structural capacity.
“As our infrastructure ages and our nation's bridges are rapidly deteriorating, the hybrid composite beams provide a good alternative to traditional beams (steel or concrete) at a lower initial and life-cycle cost due to their durability and corrosion resistance,” said Byron Danley, vice president, transportation, for Teng & Associates, the bridge's designer. “The best route to reducing the growing backlog of deteriorated bridges is to embrace new technologies like HCBs that provide longer lives for new bridges.”
The superstructure for this 57-foot, single-span bridge is comprised of six 42-inch-deep HCBs, spaced at 7-foot, 4-inch centers, supporting a conventional 8-inch-thick reinforced concrete deck. The bridge was constructed exactly the same way as a conventional concrete or steel bridge.
The HCBs are inherently stronger, lighter, and more corrosion-resistant than traditional concrete or steel beams. Manufactured by Harbor Technologies Inc., of Brunswick, Maine, the HCBs weigh one-tenth of what a typical pre-cast concrete beam weighs for the same span length. This lighter weight reduced shipping and erection costs.
As a result, all of the beams for the bridge were shipped on one truck instead of what would have taken six trucks using competing methods. They were erected using a 30-ton crane instead of a large 150- or 200-ton crane that would have been required for pre-cast concrete beams.
Associations in the Mix PCI
Irwin J. Speyer, founder and owner of Irwin Speyer-Consulting Engineers, Croton-on-Hudson, N.Y., received the 2008 Medal of Honor, the Precast/Prestressed Concrete Institute's highest award. The award recognizes a member's “outstanding service to the institute or contributions to the industry over a long period of time.” Visit www.pci.org.
Bill Emerson of Irving Materials Inc., Greenfield, Ind., won the National Ready Mixed Concrete Association's National Mixer Driver Championship, held during NRMCA's ConcreteWorks conference in Nashville, Tenn., in October. Thirty-six drivers, including state rodeo champions and association member company champions competed. For more, visit www.nrmca.org.
Randy Lindsay-Brisbin, vice president and general manager with Firebaugh Precast Inc., Colorado Springs, was named chairman of the National Precast Concrete Association at the group's annual convention in September. Joan Blecha, president of Hanson Pipe & Precast's Southeast U.S. division, received the 2008 Robert E. Yoakum Award. Steve Smart, Hy-Span systems manager with Independent Concrete Pipe Co., Indianapolis, received the Douglas G. Hoskin Award. Visit www.precast.org.