Building a Bridge, Arch by Arch, in Texas

 |  Civil & Transportation, Self-perform
One of the 12 precast concrete arches that will form the sides of the reconstructed bridge. Each one is 163 feet long and weighs approximately 700,000 pounds.

Lifting a 700,000-pound concrete arch into an upright position and setting it aside safely on a busy construction site is no easy feat. Doing it twelve times – once for each arch that will form the sides of the reconstructed West 7th Street Bridge in Fort Worth, Texas – is officially hair-raising. That’s just one of the reasons Texas Area Manager Chris Cedar has a hard time sleeping at night. He’s overseeing Sundt’s $24.1 million project to reconstruct the 980-foot-long structure over the Trinity River, which will serve as a landmark gateway connecting the city’s downtown to its new cultural district.

The new bridge will feature two, 10-foot-wide pedestrian walkways and 12 precast concrete and stainless steel arches, which are being built by Sundt’s own concrete experts. Approximately 300,000 pounds of polished stainless steel within the arches and bridge superstructure will be illuminated at night with embedded lighting.

“Technically, this is a very challenging job,” Chris explained. “We cast the arches on site adjacent to the bridge, lying flat on their sides. Then we post-tension them and install the stainless steel rods that run from the top of the arch to the tie. Once they cure and get to 6,000 psi concrete strength, we rotate them up into the vertical position and slide them over into a storage area.”

Once all of the arches are complete (three have been made so far), they’ll be placed on both sides of the existing bridge at night. Then the old bridge will be closed and demolished and the new structure will be built in its place – in just 150 calendar days.

“Each arch takes about six weeks to complete, but the amount of time we spent planning the first one was enormous,” Chris added. “We spent a lot of time preparing and doing construction engineering up front so that everything went smoothly.”