DAVIS-MONTHAN AIR FORCE BASE, Ariz. -- With 11 flying units and 152 aircraft, Davis-Monthan Air Force Base operates the busiest single runway in the Air Force. That much day-to-day activity eventually takes a toll on the airfield pavement.
This is where the Air Force Civil Engineer Center’s Airfield Pavement Evaluation team comes into play, conducting structural evaluations to determine the load-carrying capability of airfields.
Their mission is to provide accurate and timely pavement evaluations, as well as equipment, recommendations and software for the design and upkeep of pavements.
“We have a very unique capability that allows us to peer beneath the pavement surface, enabling us to identify potential problem areas or unsafe conditions on an airfield,” said U.S. Air Force Master Sgt. Mitchell Romag, AFCEC APE team superintendent.
APEs are held every 12 years for active duty bases unless specifically requested. The duration varies based on the size of the airfield, the size of the team and how often the team has been at the base in the past.
Each assessment is conducted with three different teams.
The core team uses diamond-impregnated drill bits to core through concrete, asphalt and steel reinforcement. A core sample is collected and then tested to determine the strength of the pavement. The core hole allows access to the underlying soil, which is collected for testing at the AFCEC’s premiere soil lab at Tyndall Air Force Base, Florida.
Next, the pavement condition team performs a visual inspection of the surface pavement, examining sample units and noting any distresses they see.
“The airfield is broken up into 5,000 sq. foot sections that are further broken down into sample units,” said Kristin Filler, AFCEC APE team pavement condition inspector. “The sample units are chosen at random before we come out, so that we aren’t trying to pick only the good or bad pavement.”
Finally, the test pavement team uses a device called the heavy weight deflectometer to simulate the load produced by an aircraft. The HWD is designed to impart a load pulse to the pavement surface. Deflection sensors, mounted around the load plate, measure the deformation of the pavement in response to the load. Those readings are recorded and turned into a subsurface soil strength.
The results are compiled into reports that are crucial to maintain mission readiness.
“Our evaluation reports enable the base to determine which aircraft can safely operate on the airfield, as well as justify money needed for repair projects or expansions,” Romag said.
The AFCEC APE team provides evaluation services on over 2 billion sq. feet of airfield pavement all over the world, ensuring that flight lines are able to support all Department of Defense aircraft wherever they are needed.