A $65 million road-widening project in Caldwell County, N.C., will enter its fifth year of work in 2009 and all indications are that the construction will be completed next fall.
A 6.57-mi. (10.6 km) stretch of U.S. Highway 321 between Lenoir and Blowing Rock has seen almost continuous drilling, blasting, earth moving and paving, while still remaining open to most car traffic since February 2005.
Approximately 3.1 million cu. yd. (2.3 million cu m) of dirt and rock will have been moved when the job is completed. The project, in a rugged mountainous area with elevations of 2,000 to 3,000 ft. (610 to 914 m), is being done on one of the main road links between Charlotte and the Blue Ridge Mountains.
The goal of the massive project is to widen the current two-lane stretch of U.S. 321 from Kirby Mountain Road north to Blackberry Road. When it is finished, U.S. 321 will be four-lane from the Gastonia area, west of Charlotte, north through Hickory and Lenoir to within a short distance of Blowing Rock.
The current project is the second of three phases to widen U.S. 321 and make the scenic drive easier and safer for people heading to the mountains. The first project, also approximately 7 mi. (11.3 km) long, went from the intersection of U.S. 321 and N.C. 268 north to Kirby Mountain Road and was finished several years ago.
The third phase of the project, which is scheduled to begin in 2010, will widen the road to four lanes through the town of Blowing Rock and link up with an existing four-lane section of U.S. 321.
The current project was slated for completion in August 2008, but a series of problems delayed the work, including rock slides and utility line relocation early in the undertaking, a limited blasting schedule and time to figure out the logistics of removing harder-than-expected rock.
Although the final completion date is still to be determined, work should be finished on the northern-most section of the project in August 2009, while work at the southern end will last until October or November, according to Henry McDaniel, general superintendent of the project for English Construction Co. of Lynchburg, Va.
In the meantime, crews are working on two different sections of the road project. At the northern end of the job, workers are straightening the highway from what was a series of four-lane S-curves around several steep and rocky hillsides.
Farther south, work has only recently begun on drilling and blasting a 2,000-ft. long cut through the mountainside. Work has slowed there, in part, due to the fact that blasting can only be done on Tuesdays and Thursdays, and then for only two hours in the middle of each day, according to Frank Gioscio, the North Carolina Department of Transportation’s (NCDOT) resident engineer on the project. While traffic is detoured around a lot of the work area, it is halted completely when the blasting is done.
Gioscio characterized the current work as some of the most challenging of the entire project.
“One difficulty on the northern part has been just the amount of rock that we are having to blast through to straighten those S-curves,” he said. “That has probably been the most labor-intensive part of getting the job done. Now, at the southern end, where the job actually begins, as you’re coming north on U.S. 321, there’s a huge cut that we have to take down on the right hand side. That’s posing major problems, too.”
Gioscio said that the rock formations present at the southern end of the job are an amalgam of different layers and rock types, making it hard to find any consistency in the material and, therefore, difficult — and more dangerous — to handle.
“It is a granite type — we call it a weathered rock, but still a very hard rock,” he explained. “And with it being [very] layered, there are a lot of seams in it, which, when you start blasting stuff like that, the next thing you know you have a bunch of rock falling up above you because of the shaking.”
Due to the presence of that unstable rock, Gioscio said that even after traffic is allowed through the area again, the NCDOT and English Construction crews have had to pay close attention to the hillsides for falling rock.
McDaniel added that part of the project’s delay in finishing was because a method had to be found for protecting the roadway from rock falls.
“That southern end took longer to get started because of safety issues with the rock, due to it hanging over the road,” he said. “We had to develop some means to make it as safe as possible for the traveling public. In the end, the DOT got an independent engineering outfit to design a rock fall protection fence.”
Gioscio added that the rock at the northern end presented no such problems as it was more solid and could more easily be blasted and hauled away. He credited the job done by Kesco Inc., a Pennsylvania-based rock demolition company, in safely blasting all the rock on the project.
With more than 2 million tons (1.8 million t) of rock to move throughout the job, English Construction found that it was easier to crush it themselves on site. They then utilized about a third of that material in the roadway itself, with the rest slated for a series of fill pits.
“All told, about 1.5 million to 2 million cubic yards of this material ended up as waste,” Gioscio said. “Part of that rock was run through a crusher by the contractor, plus they crushed all of their aggregate base course — the stone — underneath the roadway. So, instead of buying it from a quarry, they chose to just crush what they got from the job and use that.”
Cary Glover, the equipment manager for English Construction, said that his firm utilized three Metso-brand crushers that it owned on the U.S. 321 project, including an LT110 jaw crusher, an HP300 cone crusher and an ST620 mobile screen plant. They were purchased from a rock quarry in Greensboro.
“The great thing is that a lot of that rock would have gone to waste, but was instead processed and used on the project,” Gioscio added. “That is the first time I have actually had a contractor do that on one of my jobs. It saved them a whole lot of money, saved the state money, and saved several areas from being filled up with pure rock, meaning that we didn’t have to cut down acres of trees. It was just a win-win all around.”
The differences between the northern and southern sections of the U.S. 321 project involved more than just the density of the rock, though. The elevation difference between the two locations is approximately 1,750 ft. (533 m), with the northern section being the higher end. Gioscio said that that elevation difference would really come into play this winter as the severity of the cold weather changes markedly from north to south.
“Luckily enough, where they have started to work on the southern end they have got a good situation there because they are not at the elevation that would usually give them a lot of bitter cold,” he said.
Gioscio added that as long as the weather is relatively mild in the south, drilling and blasting would probably continue through the winter. But the northern end, nearer to Blowing Rock, he explained, can often be “a totally different climate” and can see a drop of 15 to 20 degrees from the other end of the project.
Accordingly, work in the north will be almost nonexistent over the next few months, he explained.
As many as 40 workers could be found laboring at the project site at its busiest, Gioscio said, with as many as 10 to 15 people working at night during the summer months.
Along with the more than 3 million cu. yd. of rock and dirt that has been displaced in the almost four years of work, Gioscio said that about 45,000 tons (40,823 t) of base course, a concrete/asphalt mix, is set to be applied to the roadway. Another 80,000 tons (72.575 t) of intermediate asphalt will be spread and about 45,000 tons of the final surface course also will be laid.
The equipment his firm brought to the job site made moving all that material smoother, McDaniel said. At one time, a variety of articulated trucks, scrapers, motorgraders, track loaders, bulldozers and excavators, primarily Caterpillar machines, could be found moving across the job site. Now, he said, since they are at the point where they only have to remove another few hundred thousand cubic yards of earth, its only big equipment are four Cat 740 articulated trucks, along with some 631G scrapers. Glover purchased the Caterpillar pieces from Carter Machinery Co. Inc. of Salem, Va.
Glover added that the vast majority of English Construction’s heavy equipment is Caterpillar-made, but it does use machines made by other brands. For instance, two John Deere articulated trucks and a pair of 35-ton (31.7 t) Volvo trucks have been used on the U.S. 321 project, along with a Komatsu WA600 wheel loader. He purchased the John Deere machines from James River Equipment in Salem, Va., the Komatsu from Rish Equipment, also in Salem, while the Volvo equipment was bought from a broker.
As far as the Caterpillar pieces, Glover purchased them from the Salem, Va., sales office of Carter Machinery Co. Inc.
“We have been very satisfied with all our dealers and the relationships we have with them,” he said. “They really handle our needs very well.”
The big excavator that is used to load the trucks is a Kobelco SK480LC mass excavator, purchased from Stafford Equipment near Roanoke, Va.
(This story also can be found on Construction Equipment Guide’s Web site at www.constructionequipmentguide.com.) CEG