It’s never easy to make a strong run up the middle.
With the summer tourist season always front and center in Anne Arundel County, Md., officials needed to relieve traffic on the U.S. Rte. 50 bridge over the Severn River, which is a main route to the eastern shore. The answer was to add another lane to the span right between the two existing lanes. In terms of major bridge rehabilitation, it was a run. Prime designer The Wilson T. Ballard Co. and prime contractor Fay, an i+icon USA Co., completed most of the work in less than a year—260 days—which meant working straight through winter.
“It is pretty intense to go to someone and say you have 260 days to essentially widen a bridge without any major changes,” Sam Scalleat, project manager for Fay, told Roads & Bridges, “but then say you also can’t work during the day for a lot of the things, you can only do it at night, and you have to do it during the winter.”
It also is quite a feat to do a portion of the work underneath a bridge. Diaphragm segments for the new lane were installed underneath the bridge at the start of the project. Fay installed a massive temporary work platform that spanned the entire length of the belly of the bridge. Once the diaphragm segments were in place, workers demolished the existing concrete barrier on the bridge deck at night. They also removed the existing deck that separated eastbound and westbound traffic. Using concrete saws and an excavator, sections were lifted, placed in a truck and hauled away. Once the entire middle of the bridge was open, hand chipping work took place to expose existing rebar on the decks on either side.
Top channel pieces were installed above the diaphragm pieces, and pans were used in between the channel pieces so the new middle deck could be constructed. Concrete mixer trucks pulled up alongside the 6-ft-wide openings, and the concrete was placed by hand with a long straight edge.
Demolition activity and the deck assembly took place during the winter months, and between the end of January and the beginning of March crews were working multiple shifts five or six days a week.
The additional lane now allows on-ramp traffic to stay in their lane the entire length of the bridge. Before construction, traffic needed to merge onto the span.
“Everyone would get onto Rte. 50 on the exit just before the bridge and get off of 50 on the exit just after the bridge,” said Scalleat. “From what I have heard from the people who live there is traffic has drastically improved.”
Five bioretention structures—two bioretention ponds and three bioretention swales—at the corners of the bridge also were constructed.
Project: U.S. 50 over Severn River Bridge rehabilitation
Location: Anne Arundel County, Md.
Owner: Maryland DOT; State Highway Administration
Designer: The Wilson T. Ballard Co.
Contractor: Fay, an i+icon USA Co.
Length: 2,856 ft
Completion Date: Aug. 31, 2018