Sky’s the limit
After a major airfield rehabilitation and terminal expansion through 2017, the sky will be the limit for Stewart International Airport in Hudson Valley north of New York City and the airfield contractor doing the work.
Stewart International Airport is located near Newburgh and New Windsor, N.Y., at the intersection of the New York State Thruway (I-87) and I-84, and lies about 60 miles north of New York City. In 2011 over 30,000 aircraft operations were logged, and in September 2013 its removed location and long runways made it the preferred airport for international flights bringing world leaders to New York City for the 68th United Nations General Assembly.
The owner, the Port Authority of New York & New Jersey, started a 10-year, $500 million capital improvement plan to expand the airport: both runways and several of the taxiways will be rehabilitated, including the major terminal enlargement.
Rehabilitation of the runways and taxiways - a project of $143.5 million - was awarded to Tutor Perini Corporation/ Intercounty Paving Associates LLC, a joint venture, in 2013 and will last through May 2015. The project started in late 2013 with the reconstruction of the east end of Runway 9/27 at its intersection with Runway 16/34.
260,000 Tons of Asphalt
In late 2013 all four product lines of Wirtgen America had been used by Intercounty for the renovation of the runway asphalt surfaces and the widening of the runway shoulders.
“We’re also building a new high-speed turnoff to allow planes to get off the runway faster,” said Jim Egerter, paving superintendent for Intercounty Paving Associates. In 2013 Intercounty milled one inch off the existing runway surface, and replaced that with varying depths of polymer-modified hot mix asphalt to even out the undulating surface. The mix is an FAA spec, the majority of which is 3/8-in. stone with some half-inch, and 5 percent liquid asphalt.
“One area is going up 30 in., while other areas only go up 3 in.,” Egerter said. “Everything is being leveled up to -3 in., and then a 3-in. top course will be placed. The pavements will exhibit a 1.5 percent pitch from centerline, and shoulder pitch up to 3 percent.” Asphalt is supplied by an on-site plant. Quite a challenge, with 45,000 tons and another 25,000 tons, each to be supplied within 14 days.
The same aggregate mix will be placed on the shoulders, but with a warm mix asphalt design incorporating Evotherm warm mix modifier. For the shoulders, reclaimed asphalt pavement (RAP) millings from the runways were placed as a 6-in. subbase, which was topped by 4-in. of macadam plant mix, ¾-in. stone with PG 64-22 oil. It was topped by 3 in. of the warm mix asphalt.
“The polymer-modifier main line lifts were stiff, and hard to place,” Egerter said. “We used a Vögele 2100-2 with high density compaction at the screed, so the rollers didn’t have to work as hard. We placed the pavement at 25-ft. widths, so were able to work in three pulls on either side of the centerline. The screed is heavy enough to perform across the 25 ft. width. We’ve used other pavers at that width and have had a hard time keeping consistant grade control that wide. We purchased the Super 2100-2 for this job because we either had to use one paver 25 ft. wide, or two pavers in echelon centered 12.5 ft.”
Out of the paver, Intercounty was getting 86 to 88 percent compaction with its Vögele TP2 screed, and then three Hamm rollers were going to work, an HD+ 140 HF doing breakdown, the HD+ 120 HF as an intermediate, and an HD+ 140 VO doing finish work. Target compaction spec is 98 percent or better on the mat, and 96 on the joint.
Milling with the new W 250i
One of Intercounty Paving’s new Wirtgen cold mills has done the bulk of the milling, but at one point five Wirtgen W 250 mills were working for 17 hours straight. Intercounty could do this because in early 2013 it converted its entire inventory of 10 cold mills to an all-Wirtgen fleet. Of the mills, two are standard W 250s, and eight are the new Tier 4-interim- compliant W 250i. Of them, four are half-lane, and six are full-lane machines.
The Wirtgen W 250 also is being used to fine-tune paved profiles. “Slow but steady movement with a high drum speed is the key. The pattern is achieved by an 18-mm drum run at high-speed, which is 2100 rpms. It’s a slow process, but the benefit is a smooth pattern. It’s not exactly the fine-texture pattern, but it’s a much smoother process with an 18-mm drum than you normally would have,“ said Frank Lizza, General Manager, Intercounty Paving Associates.
Kleemann mobile jaw crusher Mobirex MR 110 ZS in a show of force
Not only were Wirtgen, Hamm and Vögele equipment used this year at Stewart International Airport, but for a while a Kleemann Mobirex MR 110 ZS mobile jaw crasher was put to work in processing demolition concrete resulting from the runway expansion.
Because the expansion encroached on grassy areas, and the state permit required any such losses to be replaced, those lost areas were “mitigated” by removal of aging, unused concrete aprons and conversion of that space to grassland. “We also will have to use recycled concrete aggregate in the new taxiways and runway pavements, not millings. So we crushed and stockpiled it,” Egerter explained.
Joe LaPlaca, Intercounty Paving’s superintendent of milling, was thrilled especially by the miserly fuel consumption of Wirtgen mills. “We got the first W 250 with 7-ft., 2-in. cutter, and we used it on our first job this season, and we’re cutting shoulders with it, while doing main line with our existing 12-ft. mill,” LaPlaca said. “We were getting an average savings of 70 gal. per night versus our other 7-ft machine, about 50 percent savings.”
Frank Lizza on the other hand is glad of the clearly decreased costs for materials and staff. “The SUPER 2100-2 with its 25-ft. screed enables us to pave the runway in six pulls with a single machine, rather than two pavers and two crews.” Using a single SUPER 2100-2 cut quality control costs as well. “It allows us to eliminate half the longitudinal joints on the job, and half the testing at the same time,” Lizza said. “It was a good idea from the point of quality control, as well as man hours. While the paver cost more than other pavers, the size of this job – 260,000 tons through next year – makes it feasible.”
Now, with its tested inventory of products from Wirtgen Group, Intercounty Paving is well positioned to tackle future projects in the Empire State and elsewhere in the Northeast. “We look at our use of this new equipment here as training for projects to come,” Lizza said. “We are looking to stay with this kind of work, and these tools and equipment will help us perfect our operations and keep us at the forefront of contractors in this industry.”