PERMANENT DEFORMATIONS DURING TRAFFIC TESTS ON FLEXIBLE PAVEMENTS AT THE NATIONAL AIRPORT PAVEMENT TEST FACILITY. IN: AIRFIELD PAVEMENTS. CHALLENGES AND NEW TECHNOLOGIES

The purpose of this paper is to discuss, examine and compare measurements of permanent deformation during individual wander cycles from three different sources: internal displacements, transverse profiles, and straightedge rut depths. Measurements of permanent deformations are presented from traffic tests on a stabilized base flexible pavement test item at the Federal Aviation Administration's (FAA) National Pavement Test Facility (NAPTF). The tests were run with four and six wheel gear configurations at wheel loads of 20.4 tons and over a total wander width of 3.66 m. The test item was trafficked to structure failure with permanent deformations at the surface evidenced by rut depths of over 100mm and upheaval at the sides of the ruts in excess of 25 mm.