About the NAPTF
The FAA operates a state-of-the-art, full-scale pavement test facility dedicated solely to airport pavement research. Located at the William J. Hughes Technical Center near Atlantic City, New Jersey, the National Airport Pavement Test Facility (NAPTF) provides high quality, accelerated test data from rigid and flexible pavements subjected to simulated aircraft traffic. Construction of the facility was completed in April 1999. Major features of the National Airport Pavement Test Facility are:
- Fully enclosed instrumented test track 900 feet long by 60 feet wide.
- Computerized data acquisition system.
- Rail-based test vehicle capable of simulating aircraft weighing up to 1.3 million pounds.
- Up to 20 test wheels capable of being configured to represent two complete landing gear trucks. Each truck having 1 to 10 wheels per truck.
- Wheel loads independently adjustable up to 75,000 pounds per wheel.
- Controlled aircraft wander simulation.
The test track can be divided into independent test items on three subgrade classifications - low strength, medium strength and high strength. Test items will be trafficked to failure and then reconstructed. In this way, a variety of pavement structures can be tested, including both rigid and flexible designs incorporating unbound aggregate and stabilized bases. Current plans are for the test pavements to be replaced and tested to failure on an 18-month cycle. A construction cycle includes test pavement construction, instrumentation installation, traffic tests to failure, post traffic testing (trenching activities and other tests), and pavement removal. All pertinent data and information collected at the NAPTF is arranged by construction cycles.
The rail-based test vehicle has two loading carriages that can be configured for up to six wheels per carriage with loads up to 333.75 kN (75,000 lbs) per wheel. The test vehicle is programmed for a controlled aircraft wander simulation.
Sensors have been embedded in the test items to collect data. Sensors are of two types: static and dynamic. Static sensors monitor temperature, moisture and crack status (resistance) on an hourly basis. Dynamic sensors measure quantities such as strain and pavement deflection in response to the load, and are triggered by the vehicle operations. Sensor data collected during traffic test operations will be processed and stored in a computer database maintained on-site. This database will facilitate retrieval of the data for later analysis.