The Logan project presented storage challenges as well. Aggregate Industries needed a constant and reliable supply of about 700 tons of lime. It also had to manage the 70,000 tons of RAP milled from the runway and hauled to the Saugus plant. "Managing the incoming material was a project in itself," Hanbury says. The company had a Dresser dozer on hand full time to push the loads and maintain a safe, level area for the trucks that were dumping the RAP.
Quality control was managed by veteran manager Ron Tardiff and his team, who were based in Saugus. "The final mix design was the result of over two months of lab work and testing," Tardiff says. "For the first time at Logan, we used latex, hydrated lime and RAP in the asphalt, so quality control became even more critical."
The milling operation
At the airport, Ed Mulloy, milling division manager for Aggregate Industries, was responsible for the three five-person milling crews, which were equipped with three CAT PM 565B one-half lane cold planers, two Roadtec RX-10 trimmers and three CAT skid steers, which aided the clean-up operation.
The runway and shoulder areas were planed to three different depths. The 50-foot-wide shoulders on either side of the runway were planed to a depth of two inches. The transition area between the shoulder and the main portion of the runway was planed to a depth of between two and four inches, while the actual take-off and landing area of the 150-foot-wide runway was milled to a depth of between eight to more than 10 inches.
In order to keep up with the project's demanding timeframe, the Cat cold planers milled the runway at a rate of 20 to 30 feet per minute working extended shifts around-the-clock.
One of the challenges facing the milling crew was getting the millings away from the site. "It was a major task," says Mulloy. "We were using 35 trucks per day to haul out 840 tons to the round or approximately 4,000 tons per shift."
The paving process
The project's tight timeframe required the paving crews to begin paving as soon as the milling was completed.
An eight-person crew worked varying shifts days and nights to pave the runway. The RS-1 Tack Coat was applied with the company's Etnyre 2,000-gallon distributor truck. Paving was done with a CAT 1055B paver equipped with a 1020-B Extend-A-Mat screed, two Ingersoll-Rand DD-130 vibratory asphalt compactors, and one Ingersoll-Rand DD-110 vibratory asphalt compactor. The paving was done in three lifts with 12.5-foot passes at a depth of three inches per lift.
Paving Division Project Manager Dennis Horan, who has supervised many projects at Logan Airport over the years, was impressed with the production volumes.
"On our best day, we paved 5,400 tons in one shift," says Horan. "Even with the large volumes and sometimes tight work areas, we are proud of our safety record on the project and the fact that not a single injury or incident occurred."
In addition to the accelerated schedule for completing Runway 4L 22R, Aggregate Industries had to schedule milling and paving work around the airport's flight schedules for nine intersecting taxiways that remained in use. Aggregate Industries was given four days to mill and pave the intersections, utilizing weekend closures built into the accelerated schedule.
When Aggregate Industries completed its portion of the paving project on June 11, it had exceeded Massport's stringent standards for the project.
"We have kept at 106 percent of standards, both at the mix plant and on-site," Andersson says. "The success of this project is a true reflection of the expertise and dedication of our entire team. It was a group effort, and demonstrates our ability to rise to the challenges of the most demanding projects in our industry."