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|Federal Highway Administration > Publications > Public Roads > Vol. 67 · No. 4 > Building a Bridge from Yesteryear|
Building a Bridge from Yesteryear
by Eric Gorton
In this historic restoration, the Virginia DOT kept one eye on the past and the other on the future.
When construction crews removed the old Goshen Bridge's last truss in October 2001, it was an odd sight indeed. The historic bridge had carried State Route 746 over the Calfpasture River in Goshen, VA, for as long as any resident of this picturesque western Virginia town could remember.
The bridge's absence was only temporary-by July 2002, the truss bridge was back in place. With a galvanized finish, the two-span bridge had taken on a brand-new appearance that no current resident of Goshen had seen before. Gone was the familiar, dilapidated structure spotted with rust and peeling paint, with half of its timber deck restricted due to weight limitations.
The mission for the Virginia Department of Transportation (VDOT): Restore the bridge to the original appearance it had when it was built in 1891, using as many of the original parts as possible.
"It's a shining example of what can be done when all parties are committed to the preservation of historic structures," says Claude Napier, a bridge engineer responsible for the Federal Highway Administration's (FHWA) bridge program in Virginia and a member of VDOT's Historic Structures Task Group. Restoration of the bridge was done with "an eye for the past and an eye for the future,'' says VDOT senior structural engineer Robert ("Robbie") Saufley.
Restoring a Treasure
VDOT personnel measured and photographed every inch of the old bridge, which is listed on the National Register of Historic Places and the Virginia Landmarks Register. They had to create new blueprints because the original drawings were no longer in existence.
The restored bridge retained the appearance of the original, including round-headed bolts that look like rivets. But stronger steel and other improvements increased its capacity from 5.4 metric tons (6 tons) to more than 18 metric tons (20 tons), strong enough for fire trucks, schoolbuses, and other heavy vehicles that could not use it before. The makeover also involved restoring the bridge's stone abutments and pier, and replacing the timber deck with a new glue-laminated deck.
"They've done a spectacular job being true to the original structure," says Al Hodson, who researched the history of the bridge and rehabilitation options in the mid-1990s while working on a master's degree in civil engineering at the University of Virginia.
During the reopening ceremony, Goshen Mayor Darell V. Sprouse said that the bridge "can again be looked at with pride and satisfaction. . . knowing that yet another great Virginia treasure of the past has been [restored]."
Building a 19th Century Bridge with 21st Century Technology
The Goshen Bridge was state-ofthe-art for its day, carrying two lanes of traffic and designed to handle the weight of electric streetcars. Built by the Groton Bridge & Mfg. Co. of Groton, NY, the bridge measured 79 meters (260 feet) in length, with a pair of trusses about 6 meters (20 feet) above the water.
Pins and rivets held the bridge together. Back in 1891, the builders used die forging and loop welding to shape pinholes at the ends of the steel members. VDOT looked into creating replacement members using the same fabrication processes that produced the originals. But according to VDOT designer Saufley, the original processes, such as die forging and loop welding, were limited, expensive, and undesirable from a structural standpoint. Instead, VDOT elected to fabricate new steel, using computer-controlled machines.
"It's unique because we've never worked on a 100-year-old bridge before," says Mike Cumber, head of engineering at Structural Steel Products Corporation of Clayton, NC. "Just trying to use our new technology to match up to 100-year-old steel is a challenge."
The first step for Cumber and his coworkers was putting all the measurements into AutoCAD® and making sure that the components would go back together the way they were originally. Using Saufley's measurements, Cumber entered dimensions for all the elements- from bolt heads to the largest steel members-into the program to create a complete scale diagram. Although the computer simplified some things, Cumber notes that "a lot of brain work went into it," adding that the original basic drafting principles still applied.
Using contemporary methods brings out an appreciation for those used more than 100 years ago, he adds. "When you go back and look at some of the calculations that people had to do by hand, it's almost like artwork."
Once the measurements were accurate and the designs completed, specifications for the replacement parts were stored on computer disks. The disks were taken to the shop floor and fed into computers that controlled plasma cutters and other machines. As many as six of the largest members could be cut out of a single sheet of steel, already in the necessary shape without any of the muscle required a century ago. The new and salvaged parts were galvanized to reduce maintenance and provide longer protection against rust and corrosion than is possible with paint.
Grandest Boulevard Of the South
A century ago, the Goshen Land and Improvement Company commissioned the bridge to connect the east and west sides of its booming company town. Goshen was to become the "Iron Centre of America," according to the research by graduate research assistant Hodson.
In late May 1890, the company issued shares of stock totaling $175,000. The group quickly purchased land on both sides of the Calfpasture River and platted thousands of commercial and residential lots for its new steel-manufacturing town. Industrial sites were built near the river at the southern end of town, and large home sites were planned for a hillside between Mill Creek and the Calfpasture River. Surveyors plotted about 9,000 lots on about 324 hectares (800 acres).
The company built an electric rail-car manufacturing facility on the east side of the Calfpasture River. That factory was to employ 300 to 500 workers. By June 1891, the lumberyard for the facility covered 5.7 hectares (14 acres).
Another investing group purchased the Victoria Furnace, which was capable of producing up to 181 metric tons (200 tons) of iron per day from ore that was mined at nearby Bratton's Run, south of Goshen. Investors quickly planned a rolling mill, pipe factory, nail works, and other steel-related production facilities. They also planned a box factory, door factory, and three brickworks capable of producing 30,000 bricks a day. By late June, construction began on a rolling mill whose 400 workers manufactured steel tubing.
Goshen was like many villages in western Virginia experiencing the land boom of the 1890s. Opportunities seemed limitless for those willing to invest capital with speculators. Enthralled by the combination of mineral resources and railroad access to the larger markets of the northeast, investors contributed heavily to the Goshen Land and Improvement Company.
The boom in Goshen was at full throttle. By mid-June, the town's population reached several hundred. Speculators expected it to reach 6,000 during the following year. The Goshen Land and Improvement Company remodeled existing hotels to address the town's housing crunch and to provide hospitable accommodations for potential investors. The company created several spin-off firms to provide other housing and infrastructure in the new town. The only thing limiting the pace of housing construction, and, in turn, full production from the mills, was the shortage of laborers available to wield hammers and drive nails.
The Goshen Land and Improvement Company laid out Maury Avenue, the town's new Main Street, along the line of the existing county road to Lexington, VA. The developers planned for Maury Avenue to be one of the "grandest boulevards in the South," a road 24 meters (80 feet) wide and lit by gas street lights. According to Hodson's report, "Goshen Bridge Rehabilitation Options: Balancing Structural Requirements with Historic Preservation Concerns, the road was to cross the river ". . . on a large iron bridge built with width and strength sufficient for the passage of electric railway cars. On one side will be a foot way.'' The previous year, the Goshen Land and Improvement Company had offered to combine funds with Rockbridge County to relocate a bridge already under construction. The bridge relocation plan would serve both parties well. The Land and Improvement Company would assume the majority of the construction and maintenance costs of a bigger, grander bridge, and any traffic heading from Goshen to Lexington would have to pass through the company town. Rockbridge County was to receive a much larger, stronger bridge at no cost to the county. Additionally, Maury Avenue passed the site of the electric car manufacturing facility, which supporters thought would become one of Goshen's largest industries.
June 1891, about 6 months behind schedule and at a cost exceeding $16,000, more than double the estimated cost of $7,000. No known description details the reason for the cost overrun.
Goshen's boom times ended abruptly in 1893, largely due to economic troubles in Europe. A London-based international banker had failed that year, and the failure affected the U.S. Treasury. The Panic of 1893 set in, also fueled by the Treasury's own gold shortages. Goshen, like many other Virginia boomtowns, never recovered. The town dwindled in size as laborers sought employment elsewhere.
In the early 20th century, Andrew Carnegie's United States Steel Corporation monopolized the steel industry and crippled many small southern steel producers. Goshen's population fell to several hundred, where it essentially remains today. During the first half of the 20th century, many prominent vestiges of Goshen's boom disappeared, leaving the Goshen Bridge as the most visible symbol of the speculators' hopes that the town would become "The Iron Centre of America."
Bridge to the Past
Although the bridge is once again a useful structure, its importance goes far beyond its utilitarian purpose, says Kathleen Kilpatrick, director of the Virginia Department of Historic Resources. Historic preservation "is not so much about old buildings and old structures," she says, "but about people and communities and serving communities by rebuilding on the assets that we have through our historic resources. They are cultural, economic, and educational assets that we have a responsibility to invest in for the future.
"What we do today and the efforts that we make to preserve our resources are about ensuring a strong and vital future for the citizens of the future. It's no secret that the strongest communities are not the cookie-cutter communities and subdivisions, but places like Goshen that have a sense of character and identity and connectedness to their past . . . And what better symbol of that important connectedness [is there] than a bridge?"
George M. Clendenin, P.E., State structure and bridge engineer at VDOT, adds: "The extent of our efforts demonstrates our commitment to carrying out the recommendations of our historic bridge management plan . . . By doing the design of the rehabilitation inhouse, VDOT has had the opportunity to relearn historic technology and develop new approaches to rehabilitation work."
Summing it up, FHWA's Napier says: "The Goshen Bridge is an excellent example of how to preserve a historic structure where practical and still maintain the mobility, safety, and economic opportunities that the existing highway and the bridge provide."
Eric Gorton is a public relations assistant for VDOT and works out of the Staunton District Office. He joined VDOT in September 2000 after spending 12 years as a newspaper reporter and editor. He has a bachelor's degree in communications from James Madison University.
For more information, contact Eric Gorton at 540-332-9264 or by e-mail at email@example.com.
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