Behind the installation of the world’s first precast network arch bridge in Fort Worth (PHOTOS & VIDEO)

Updated Jun 6, 2013
Workers guide in one of the precast arches of Fort Worth’s new West 7th Street bridge. Each arch is 163.5 feet long.Workers guide in one of the precast arches of Fort Worth’s new West 7th Street bridge. Each arch is 163.5 feet long.

Faced with closing a heavily used bridge to Fort Worth’s city center for 12 months, officials at the Texas Department of Transportation came up with a better plan.

Rather than replace the 100-year-old structure with a conventional bridge, TxDOT engineers designed the world’s first precast network arch bridge. The innovative design cut seven months out of the construction time and will create an elegant series of arches leading into the city’s cultural district.

“The idea was to turn to our success in precast technology and mass production, only we knew we wanted something more attractive for the West 7th Street bridge,” says TxDOT structural engineer Dean Van Landuyt. “Aesthetics were paramount. We tried to do something worthy of the great buildings and great architects who have worked in the city.”

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Fort Worth is home to buildings designed by such notable architects as Louis Kahn, Tado Ando and Renzo Piano.

TxDOT has a long history of building low-cost, precast concrete bridges. This first of a kind precast network arch bridge met the agency’s goals of reduced construction time, aesthetic beauty and improved mobility and safety.  The design also offers more pedestrian access than conventional designs.

The first two of twelve arches were recently placed, and the bridge is expected to be finished and open to the public this fall. Check out the rest of these amazing photos, courtesy of TxDOT, below.

Contractor Sundt Construction of San Antonio built all the pre-cast arches at a nearby yard.Contractor Sundt Construction of San Antonio built all the pre-cast arches at a nearby yard.

 

The bridge segments are lowered onto wheeled cribbing for the short ride to their final destination.The bridge segments are lowered onto wheeled cribbing for the short ride to their final destination.

 

Workers guide in one of the precast arches of Fort Worth’s new West 7th Street bridge. Each arch is 163.5 feet long.Workers guide in one of the precast arches of Fort Worth’s new West 7th Street bridge. Each arch is 163.5 feet long.

 

The network of stainless steel hangers with clevises and tie-beam connection protect pedestrians from traffic and allow pedestrians and motorists clear views of the river.The network of stainless steel hangers with clevises and tie-beam connection protect pedestrians from traffic and allow pedestrians and motorists clear views of the river.

 

Massive cranes are needed to lift the cranes off the cribbing and place the segments, but the construction method will cut seven months out of what would have been a year long project.Massive cranes are needed to lift the cranes off the cribbing and place the segments, but the construction method will cut seven months out of what would have been a year long project.

 

Powerlift. Each arched segment weighs 300 tons.Powerlift. Each arched segment weighs 300 tons.

 

One arch down, 11 more to go. The project is due for completion this fall.One arch down, 11 more to go. The project is due for completion this fall.