Firm Uses Temporary Bridges Over Sensitive Waterways

Fri June 10, 2005 - Southeast Edition
Gwenyth Laird Pernie

Implementation of “green” construction techniques in the planning and design of bridge projects are increasingly becoming a priority to transportation and environmental officials, particularly in environmentally sensitive areas such as wetlands and waterway.

In July 2003, Vecellio & Grogan began new construction of a 7.75-mi. (12.5 km) section of Interstate 540, also known as Northern Wake Expressway, in northeast Raleigh, NC. This new portion of divided highway will be six-lanes, running east of U.S. 1 to U.S. 64 and includes 10 bridges. Total contract amount is $67 million.

According to Matt Farley, senior bridge engineer of Vecellio & Grogan, two sets of twin bridges are being constructed to cross over both the Neuse River and Beaverdam Lake.

“In order to minimize the impact to the lake and river, temporary work bridges, or platforms, are being constructed in each of the waterways,” Farley said. “Historically, crushed rocks would be placed in the waterways, creating an island to work from, but heightened environmental awareness has made the use of temporary bridges the preferred choice.”

The 30-ft. (9.1 m) wide temporary bridges, which are being constructed with steel pilings, piers and wooded decks, are being built in 30-ft. sections directly between the future twin bridges.

“As each section is completed an American HC110 crane is walked out onto the bridge and the next section is built,” Farley said.

The temporary lake bridge is 800 ft. (244 m) long and the river bridge will be 600 ft. (183 m) long. The total cost for both bridges is $1.8 million. Both are designed to support the cranes and other heavy equipment used to build the permanent bridges, which will be constructed of concrete girder spans. Once one of the permanent bridges in each waterway is completed to the point that work on its super-structure can begin, the platforms will be disassembled and removed.

By April 2005, crews no longer needed one of the temporary bridges over the lake.

It was removed, 30 ft. (9.1 m) at a time, by means of a crane, vibratory pile hammer and loader.

“Work has now begun on the super-structure of the first permanent twin bridge over the lake. Construction of the second twin bridge will be done from the completed permanent bridge,” Farley said.

“The temporary bridge over the Neuse River is 40 percent complete,” Farley stated.

As for the rest of the project, Vecellio & Grogan will handle the grading, paving and bridge construction. Coastal Caisson, subcontracted by Vecellio & Grogan, will handle the drill shaft work for the bridges. The North Carolina Department of Transportation provided the design work.

As of early May 2005, approximately 60 percent of the highway construction was complete. The U.S. 64 bridge was totally completed; 80 percent of the Old Milburnie bridge was complete; and 60 percent of the Buffaloe Road Bridge is complete. The Fox Road Bridge construction began in mid-May. The 290 ft. construction of the North-South Connector (left and right lanes), which will be the longest single span bridge in North Carolina, will start in July.

“Approximately 3 million cubic yards of excavation will be needed for the 7.75 miles of project,” Farley stated. “For the roadway alone about 266,000 square meters of concrete pavement will be utilized.”

Minding the surrounding environment has been at the forefront of the contractors’ minds throughout the project.

“The biggest challenge during the construction of the waterway bridges has been staying within the permit regulations in such an environmentally sensitive area,” Farley said. “Other than that, the project has progressed on schedule and uneventfully.”

The estimated date for completion of the entire project is April 2006. CEG