Slow-Rolling Response Tests on the Test Pavements at the National Airport Pavement Test Facility (NAPTF) 

Airport pavement thickness design procedures predict a significant amount of interaction between the loads from multiple-wheel and closely spaced multipletruck landing gear configurations. But the true degree of interaction is not known, and measurements from full-scale tests are required to determine how closely wheels and trucks can be spaced without significant load interaction. As a supplement to traffic tests run to failure at a later date, pavement response tests were performed to study the wheel load interaction effects. Pavement responses (stresses, strains, deflections, etc.) were measured at various depths in each of the nine pavement test items at the National Airport Pavement Test Facility (NAPTF) for different combinations of wheel configurations, truck configurations, and load levels. Moving loads were applied at a speed of 0.15 m/sec (0.5 feet/second). A total of 522 tests were performed on six flexible pavement test items and 108 tests were performed on three rigid pavement test items. This paper describes the response test objectives and test procedures. Some typical pavement responses are presented. Data from the response tests is being analyzed at the FAA Center of Excellence for Airport Technology at the University of Illinois. The raw data is also available from the FAA for independent analysis.

Authors: Gordon F. Hayhoe, Robert Cornwell, Navneet Garg