I-85 bridge foundation complete; girders, spans being added
By Karissa Minn
SALISBURY — This spring, drivers headed north from Rowan County on Interstate 85 should be crossing the new Yadkin River Bridge.
The bridge’s foundation is complete, but girders and spans are still being added to the lines of columns rising from the river.
Crews have laid down asphalt and concrete on a mile of new road-way on the interstate since they started paving in late September.
The first phase of the I-85 Corridor Improvement Project will realign and widen a 3.3-mile stretch of the interstate, which runs from Long Ferry Road in Rowan County to just north of N.C. 150 in Davison County. It also will replace eight bridges.
The northbound lanes are scheduled to be completed by May, according to the N.C. Department of Transportation.
One of the two spans of the new Yadkin River Bridge also will be opened for traffic in a few months.
“Northbound traffic will be moved by the end of March,” said Adam Mathews, project manager with contractor Flatiron-Lane. “By next summer, none of the traffic will be on there. It will all be on the new bridge.”
The southbound lanes are set to be finished by November 2012.
In the paving process, lime and cement are added to the dirt to firm up the road bed. Then, a 3-inch drainage layer of gravel is placed on top of the dirt, allowing the road to better withstand freezing temperatures and avoid cracking.
Next comes an inch and a half of asphalt, and finally, 14 inches of concrete. To guide the inevitable cracking, the road surface is saw-cut to a few inches deep.
“Concrete is going to crack no matter what, so we’ll make it crack where we want it to,” Mathews said Wednesday.
Rows of metal rods placed in the concrete keep the slabs from moving around when they do crack apart, Mathews said. When the project is finished, the saw cuts will be sealed with silicone to keep out water.
Crews can pour concrete at temperatures as low as 35 degrees, said Tim Canup, assistant resident engineer with the Department of Transportation. If it gets below that at night, they cover the fresh road surface to prevent freezing.
“The days are shorter, but that doesn’t necessarily mean they stop any earlier,” Canup said Wednesday. “On warm days like this, they can work well into the evening.”
The first phase of the project began in September 2010 and is set to be finished by January 2013.
Also included in this phase is the removal of the Clark Road interchange and the reconstruction of the N.C. 150 interchange.
The ramp from northbound I-85 to N.C. 150 opened Oct. 28, after being closed for a year while crews replaced it.
The three remaining ramps are under construction. The Department of Transportation says it plans to open them to traffic by late 2012.
Progress in numbers
As of Dec. 12, crews working on the Interstate 85 improvements at the Yadkin River have:
• moved 960,975 cubic yards of dirt, the equivalent of 2,988 Olympic-sized swimming pools, to build the road bed.
• poured more than 15,000 tons of concrete. The finished project will contain 95,000 cubic yards of concrete.
• on average, paved more than 1,500 feet of the road per day.
• installed about three miles of girders. Seven miles will be needed for the project.
Also, the paved road on each of the bridges will be 72 feet wide, including four 12-foot travel lanes and two 12-foot shoulders. The girders that support the bridges are 7 feet deep and 140 feet long. Each one weighs about 80 tons.
Contact reporter Karissa Minn at 704-797-4222. Twitter: twitter.com/postcopolitics Facebook: facebook.com/ Karissa.SalisburyPost