Newark Airport Runway

Abstract

Loose aggregate raveling from a runway surface creates a risk for foreign object damage to aircraft. To reduce the probability of surface raveling and cracking, engineers often use polymer-modified asphalt (PMA), which has been widely shown to reduce pavement surface damage. Unfortunately, every paving paradigm has exceptions, including performance expectations for PMA. When two high-quality PMA pavement sections exhibited raveling before any damage was noted in the conventional PG 64-22 mix, a forensic analysis was begun. Numerous binder and mixture properties were evaluated, with particular emphasis on moisture damage and accelerated aging coefficients that might indicate binder hardening or embrittlement. The initial (2004) forensic analysis of these 5-year-old pavements eliminated moisture damage as the cause and focused primarily on binder aging. Although significant increases in binder and mixture moduli were noted near the surface as the pavement aged, no definitive failure criteria could be directly tied to the initiation of raveling or surface cracking. This older forensic study is revisited to evaluate the recently proposed Glover–Rowe parameter as a predictor of age-induced surface damage. This damage index, which is easily measured in a dynamic shear rheometer at intermediate temperatures, has been proposed as a materials indicator for timing pavement preservation strategies. For this limited field study, the Glover–Rowe parameter correctly predicted the unexpected onset of raveling for the two PMA sections, as well as the good performance of the conventional section, but other common aging or cracking parameters failed to rank the materials correctly. Further field validation of this parameter is recommended.