Three laboratories of the U.S. Army Engineer Research and Development Center -- Cold Regions Research and Engineering Laboratory, Construction Engineering Research Laboratory and Geotechnical and Structures Laboratory -- brought their expertise to solve the problem of permafrost damage at Thule Air Base in Northwest Greenland.
“The Air Base in Thule has the very important mission of tracking and detection. They are an early-warning surveillance security for the United States. It is of great benefit to the nation to make sure Thule is operational,” said Kevin Bjella, research civil engineer at CRREL.
The airfield and two structures at Thule Air Base had experienced damage from permafrost thaw.
Building on frozen ground in high-latitude regions presents many challenges for construction of any kind. CRREL was tasked with finding ways to mitigate the issues of infrastructure on the frozen ground and provide new ways of construction.
CRREL partnered with CERL to find ways to mitigate thaw settlement damage to existing structures. These methods would need to account for summer thaw and ensure the thaw would not reach the permafrost, which would compromise the stability of the structures built on it.
Bjella and James Wilcoski, structural engineer at CERL, worked together to complete a structural assessment of two buildings at Thule Air Base. The most critical building was the primary facility for the Ballistic Missile Early Warning System.
The assessment of both buildings revealed previous modifications and remodeling projects to the structures had caused settlement and damage.
The team successfully developed mitigation strategies to reverse the impact of previous modifications and helped define upgrade recommendations to ensure the buildings’ future safety. The Air Force is now working with the Base contractor on implementing the modifications.
In addition, CRREL provided the geological assessment and foundation alternatives for the Corps’ New York District on the construction of four military structures, successfully addressing concerns of permafrost thaw and ensuring long-term stability for the structures.
Bjella also worked alongside John Rushing, Jesse Doyle and Jeremy Robinson, research civil engineers at GSL, in the successful quality reconstruction of the runway at Thule Air Base. CRREL led a multi-phase investigation into the current method of permafrost mitigation, the painting of four million square feet of airfield asphalt pavement white. Painting pavements white in cold regions is a Cold War-era method of preventing damage by thawing permafrost; however, this technique causes aircraft braking problems and is very costly.
The ERDC investigation revealed that much of the runway did not require thaw mitigation and was still in good condition. Thule’s runway had not seen new asphalt since 1991. During a recent repaving during the summers of 2015 and 2016, researchers successfully attempted a repaving design that incorporated buried extruded polystyrene (foam insulation boards) to prevent permafrost thaw at the most critical locations, or approximately 18 percent of the runway.
ERDC support led to successful, resilient reconstruction of the entire runway ahead of schedule, ensuring normal flight operations could quickly resume.
The GSL team provided continual inspection of the paving operation and helped identify deficiencies. They were able to troubleshoot problems as they occurred, communicating all findings to the Air Force squadron responsible for maintaining the airfield.
“This was the first time I’ve been able to work on a project with multiple ERDC labs,” Bjella said. “I was happy to be able to demonstrate to the customer that we have this multi-faceted ability and expertise across ERDC. The Air Force was able to see ERDC effectively provide quality assurance, analysis and consultation for these projects.”
ERDC’s unique ability to combine capabilities across laboratories and disciplines gives a competitive edge and holistic solution to the Warfighter and the nation.
Bjella, Wilcoski, Rushing, Doyle and Robinson combined their expertise to remedy permafrost thaw damage, establishing a formidable team to solve the problem and create a safer, better solution for the airfield and its buildings.