PCN measurements

We use the HWD (Heavy Weight Deflectometer) device to simulate the load and impact of aircraft of different weights on the airfield pavement structure. For each measuring point, 3 measurements are made with 3 different load levels. Deflections of the pavement structure are measured at a distance of 0, 200, 300, 450, 600, 900, 1200, 1500, 1800 mm from the load center.

The following data are recorded during the measurements:

  • distance from the starting point
  • exact location with GPS coordinates
  • air temperature
  • coating surface temperature
  • temperature inside the cover (measured manually)

For each measurement point, the modulus of elasticity, the remaining life of the coating and the PCN values ​​of all structural layers are calculated. Elmod-6 analysis software is used for calculation. In addition, the characteristics of structural materials (taking into account their dependence on temperature) and parameters of different aircraft types such as weight, wheel arrangement, tire pressure and tire pattern are used as input parameters of the analysis.

The PCN method used is consistent with the latest FAA recommendations.