Analysis and evaluation of post construction failures of airport apron pavement in Ghana

Abstract

A new apron pavement for parking aircrafts was constructed in 2014, but major depressions occurred when used by aircrafts soon after the construction. Failure analysis revealed structural design inconsistent with the United States Federal Aviation Administration Design Code AC 150-5320-6E. The methodologies for the technical investigations of the failures encompassed field investigation (including visual condition survey), sampling core materials for verification tests, non-destructive and destructive tests to evaluate the integrity and characteristics of the pavement layers. The sample of cores tested in an accredited laboratory were inconsistent with the site tests. Air voids and Marshall Stability for wearing course were low. Binder specification should have been PG82, instead of PG76, which was not appropriate for aprons subjected to large static loads. The low air voids in the wearing course were linked with the compaction regime adopted. Fuel resistant polymer modified bitumen was adopted for the construction, without correct application techniques, thereby affecting the pavement performance. The key factors underlying the pavement failures were binder specifications, tenderness of the mix, compaction regime and structural design, which contributed to the immediate distress and possible long term performance of the pavement.

Keywords: Apron Pavement, Wearing course, Cores, Air voids, Marshall stability, Compacting regime, Polymer modified bitumen