Structural Evaluation and Pavement Investigation of Runway 10/28, Taxiway B7 and Taxiway E3, Dublin Airport

PMS assessed the structural condition of the existing pavement by means of Heavy Weight Deflectometer (HWD) testing, in conjunction with a programme of Ground Penetrating Radar (GPR) testing and analysis. With the structural condition of the existing pavement assessed, the Pavement Classification Number (PCN) of the runway and two taxiway sections was to be determined. HWD testing was carried out on a series of six test runs along Runway
10/28 at 3m, 9m and 15m offsets from the centreline. Four test runs were carried out on the two taxiway sections at 3m and 9m offsets from the centreline. The condition of the existing subgrade was appraised using the results from the HWD survey.
Runway 10/28 is the main runway of Dublin airport,
constructed in 1989 in PCC (concrete) and recently had a significant structural bituminous overlay applied. Taxiways also had bituminous overlay applied to increase the structural capacity of the runway. PMS were asked to carry out a structural evaluation of the overlaid runway to determine the as-built structural condition after the overlay
was complete. DAA provided aircraft traffic details which included the critical aircraft be a B777-300ER with 100,000 coverages on all three sections. The critical ACN (Aircraft Classification Number) for this aircraft was determined as an ACN of 85 for a Medium Class B subgrade. This equates to the definition of “Medium” coverage under the ICAO aircraft
rating scheme.

All sections were segmented into homogenous segments based on the D1, D7 and pavement structure information. The 85th percentile location within each segment was taken as the critical design location within each for determining a PCN for the segment. A total of three different methods were used to calculate the PCN (Pavement Classification Number) of each design segment. These included ICAO, DMG 27 (Airfield pavement design and evaluation guide) and COMFAA.