Updated Wednesday, August 13, 2014 - Paving for the runway project completed August 11. Crews are continuing to install runway edge lighting and joint sealing. Grinding, grooving, and painting will start in the near future.
The United States has two B-52 bomber squadrons and Minot is home to one of them. The base began as an Air Defense Command Base with its original runway constructed in 1957 to provide a quick route to Russia over the Arctic Circle. Minot, as part of the Air Force Global Strike Command, remains a strategically important air base to the United States.
The runway at Minot Air Force Base in Minot, N.D., has seen numerous maintenance, repair, and airfield lighting upgrade projects since its original construction in 1957 but in 2012, work began on a three-phase $67 million program to completely replace the air base’s runway.
Following an Air Force Civil Engineering Service Support Agency study of the runway’s condition in 2011, the Air Force made reconstructing the runway one of its top infrastructure priorities. In 2012, the west end of the runway was completely replaced and in 2013, crews replaced the east end.
The third and final phase, which is currently underway, required completely shutting down the runway. In April 2014, the $32.8 million construction contract began with all but a handful of Minot’s B-52s temporarily relocating to Anderson Air Base in Guam and Ellsworth Air Force Base in South Dakota.
Following the precedent set with the construction of the original runway, the new runway is paved with asphalt in 100-foot wide sections on each side and a 100-foot wide concrete lane at its center.
“The B-52 Stratofortress is in a design aircraft group with some of the largest and heaviest aircraft in the U.S. Air Force so the runway’s geometrical and pavement thickness design can accommodate other aircraft from the Air Force inventory, if necessary,” said John Hawkins, Materials and Pavements Engineer with the USACE Transportation Systems Center.
The engineering specifications and design for the project were completed through the U.S. Army Corps of Engineers, Omaha District, Engineering Division's Geotechnical Branch Soils A Section. The Transportation Systems Center, also located within the Omaha District, as mandated by HQ USACE provided design document review at the various levels of design, 35 percent and final design, and technical assistance during construction. The TSC is a mandatory center that provides technical assistance to all USACE-managed airfield pavement projects and assistance to projects managed by the Air Force.
Contractors began the project to replace the larger, remaining segment of the runway by removing the existing runway. The asphalt was milled and used to improve the surface of some of the gravel roads around the runway area on base. The remaining asphalt, all of the concrete, and the original base course was removed and hauled to an off base site where it will be crushed and reused for other purposes.
The primary contractor, Sundt, and asphalt sub-contractor Lagan, each brought batch plants onto the base and are working across the runway from the base’s cantonment area, which reduces the impacts of construction traffic, up to 200 trucks a day, to the city of Minot as well as on base.
The on-site batch plants also offer more control over the project materials and helps avoid issues caused by asphalt cooling during transport and delivery. The batch plants also provided a storage area for construction equipment and materials along with aggregates for the concrete and asphalt that were brought in via rail from Sioux Falls, S.D.
The non-reinforced concrete was primarily placed through slip-form paving in four lanes, with the two outside lanes paved first and then two narrower inside lanes to make up the crown of the runway.
Throughout the project’s construction, the contractor has taken core samples from various paving sections to ensure that the concrete meets the stringent design specifications that are aimed at providing a runway that will support another 50 years of service.
“You’re looking for an even distribution of the aggregate,” said Brad Jones, Chief of the Soils A section of the Omaha District's Geotechnical Branch. “If there isn’t enough aggregate at the surface layer, it means the concrete was overworked during placement and may experience spalling, or chipping away from the surface, and degrading the integrity of the concrete.”
“Spalling wouldn’t just impact the runway,” said Jennifer Aldrich, a project engineer overseeing construction quality on the project. “Spalling can lead to debris which can result in foreign object damage to aircraft engines over time. Our goal is to ensure airfield quality helps sustain the aircraft and provides a safe landing surface for the aircrews and their aircraft.”
The asphalt contractor Lagan, a Europe-based contractor, brought with them equipment that is growing in popularity in Europe on horizontal construction projects.
“The Vogele Super 1900-2 tracked paver, is something we haven’t seen before and hasn’t been used in this part of the United States,” said Aldrich. The paver is designed to handle a large variety of applications including placing base course, bringing it to elevation and achieving up to 94 percent compaction moving along behind a feeder which provides an uninterrupted supply of materials to the paver.
The trucks carrying the base course empty the material into the feeder which supplies the material to the paver. The next day, the same equipment is then used to place the asphalt.
Also in use is a unique three-wheeled roller, which crews are using for initial asphalt compaction. According to Aldrich, the three-wheeled roller provides tighter joint compaction between the concrete and asphalt.
With less than two months remaining on the runway paving project, crews are moving past the concrete placement and asphalt placement phase. The project is on track for completion in early October.
By the end of July, crews had completed about 90 percent of the concrete paving and a significant portion of the asphalt paving on the project.
The main portion of the 8,900 foot long runway is 14.5 inches thick and widens to 18 inches at the outer edges.
The project includes 41,400 cubic yards of concrete and 35,650 tons of asphalt.
Once paving is complete, crews will groove the surface to help direct rainfall and snowmelt away from the crown of the runway and another crew will paint the runway striping.
Work is already complete on the storm drains and crews have begun to replace airfield lighting.
Through the duration of the runway closure, a taxiway was converted to function as an emergency runway and once the B-52s and support crews return to Minot the final project phase will be to restore the light stands at the mass parking area located adjacent to the taxiway, which were removed to establish the emergency runway.