Thanks to composite materials and a bridge rehabilitation project, a badly rusted span providing access to an East Lynn Lake campground has been saved from possible demolition. The span will open to traffic in May and should serve campers for decades to come.
The project also saves taxpayers more than $135,000, since the rehab work was done at 60 percent of the cost of conventional repairs and could serve as a national demonstration project for government agencies dealing with infrastructure construction and maintenance.
The 40-year-old bridge spanning the East Fork arm of East Lynn Lake had been reduced to one traffic lane and a six-ton weight limit because of severely corroded steel support pilings. Consideration was given to closing the span after structural engineers found that up to half of some of the steel pilings supports had corroded away.
But a solution was in the works. In 2009, the Corps Engineering Research and Development Center became interested in testing the viability of using composite materials in public works projects to enhance durability and reduce maintenance costs.
A contract to conduct the study was awarded to West Virginia University's Constructed Facilities Center, a unit of the College of Engineering and Mineral Resources. Dr. Hota GangaRao, director of the CFC, had been working on ways to integrate composites into infrastructure construction and repair since the late 1980s.
With support from the National Science Foundation and the Corps R&D division, GangaRao and WVU were commissioned to test possible uses of composites on six Corps projects, ranging from the installation of new emergency gate recess filler panels made with fiber reinforced polymers at Willow Island Locks and Dam to repairing concrete lock discharge ports at Tennessee's Chickamauga Locks and Dam by wrapping them underwater with reinforced polymer fabric.
John Clarkson, a structural engineer with the Huntington District and a former student of GangaRao, praised the work ethic of the engineering students who spent hands-on time working on the bridge, completing the repairs ahead of schedule in spite of weeks of unfavorable weather. "They really jumped in here and helped us," he said.
"The students were here two or three days a week," said GangaRao. "The actual construction time here was about two-and-a-half weeks. Without the students, we couldn't have finished here that soon."
Resource Manager Dale Smith said, "The East Lynn Lake maintenance team composed of Jeremy Leslie, Howard Dyer, Bill Riffe, David Blankenship and Bart Fink used their skilled crafts and trades expertise to accelerate repairs." Repairing the bridge through conventional means would have required welding, scraping and painting the piers, but the project made that irrelevant.
Quarter-inch-thick, 20-inch-diameter jackets of fiber-reinforced polymer were placed around the corroded H-beams that made up the bridge piers. Next, sheaths of fiberglass-reinforced polymer were wrapped around the jackets. Finally, self-consolidating concrete was pumped into the voids separating the beams from the jackets.
The concrete and the polymers that encase it provide three layers of protection against future corrosion and give the bridge more than twice its original strength.
Welders or other special equipment were not needed to rehabilitate the Wayne County bridge, since "the composite jacket that goes around the piles is fastened with screws, and the fiberglass polymer that wraps around it is applied by hand," Clarkson said. "All the composite material used was bought off the shelf."
Sensors that measure corrosion, humidity and temperature have been installed in the bridge.
District Commander Col. Leon Parrott said, "When you can combine innovation with teaching and research to protect our infrastructure, it's a good thing. The technology used here can be used statewide and across the nation."