New Hampshire

The APT research program at the U.S. Army Corps of Engineers - Cold Regions Research and Engineering Laboratory (CRREL) was established in 1997. The test device is the HVS Mark IV and can accommodate dual truck tires, a single truck tire, or a C141 aircraft tire.

The load can vary between 20 kN and 111 kN on super singles or duals and up to 200 kN on C141 tires. Speeds can reach 13 km/h, which yields 700 load applications per hour in a unidirectional trafficking mode. The wheels wander up to 900 mm in increments of 50 mm.

The facility is housed in an environmentally controlled building with a battery of test cells, each of which is 6.5 m wide × 7.6 m wide × 3.7 m deep. The water table can be varied in the test cells, and the ambient air temperature can be controlled. Six freeze–thaw cycles can be simulated in a calendar year. Test sections are 6.1 m long and 1.8 m wide. The study under development aims at developing new performance criteria for subgrade strain in flexible pavements and is funded by the FHWA Pooled Fund Program.