A firm specializing in the development of hybrid-composite structural alternatives that can be used for accelerated bridge construction and offer a long service life - recently announced that construction has been completed on the High Road Bridge over Long Run Creek in Lockport Township, Ill., three months ahead of schedule.
The innovative structure, now open to traffic at High Road, is the first permanent highway installation of Hybrid-Composite Beams (HCBs), developed by the HC Bridge Company, LLC.
The existing High Road Bridge, constructed in 1935, had outlived its useful service life and was categorized as both structurally deficient and functionally obsolete. In order to reduce future maintenance costs, the new replacement structure, designed by Teng & Associates, Inc. of Chicago, Ill., utilized a new type of bridge technology - HCB - that provides an extended service life with minimal or no maintenance to the bridge girders.
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.
Byron Danley, Vice President Transportation for Teng & Associates, Inc., stated that they are always looking for innovative solutions to the problems facing their clients. "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 Danley. "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. According to John Hillman, President of HC Bridge, despite the use of the innovative framing system, 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 the traditional concrete or steel beams, providing real advantages to the Lockport Township Highway Department. Manufactured by Harbor Technologies, Inc., of Brunswick, Maine, the HCBs weigh approximately one-tenth of what a typical precast 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, and they were erected using a 30-ton crane instead of a large 150-200-ton crane that would have been required for precast concrete beams. Construction of the High Road Bridge was conducted by Herlihy Mid-Continent Company of Romeoville, Ill.
In an effort to help promote this new type of technology, Lockport Township Highway Commissioner Jack Waxweiler worked with the Illinois Department of Transportation to secure a $250,000 award grant from the Federal Highway Administration (FHWA) through the Innovative Bridge Research and Design (IBRD) Program. Established by FHWA, IBRD provides discretionary funding to local government agencies to help facilitate innovation in advancing the technology for construction of our nation's bridge infrastructure.