Investigation of shear failure in airport asphalt pavements under aircraft ground manoeuvring

Abstract

This study aimed to investigate the effect of aircraft ground manoeuvring operations on shear failure potential of airfield asphalt pavements using the multi-axial stress state criteria. A numerical modelling study was conducted to characterise the stress state in the asphalt layer using an advanced three-dimensional (3-D) finite element (FE) model that has been validated in previous studies. The complex tyre–pavement interactions were characterised with non-uniform distributions of tyre–pavement contact stresses at vertical and tangential directions. Different tyre rolling conditions caused by aircraft ground manoeuvring during landing were simulated including free rolling, full-braking, and turning. The effects of takeoff weight and operating speed were also considered in the analysis. The multi-axial stress states in the bulk asphalt material and at the asphalt layer interface were analysed by means of the Mohr–Coulomb failure criteria in a normal-shear stress plane. The results emphasised the importance of tyre–pavement interaction and considering multi-axial stress state criterion for analysis of pavement shear failure. Aircraft braking or turning significantly increases the shear failure potential in the bulk material and at the asphalt layer interface due to the tangential stresses applied on pavement surface. The effects of aircraft weight and operating speed on pavement shear failure were limited compared to aircraft manoeuvring. The analysis of stress states in the asphalt layer sheds light on the requirement of shear strength and selection of laboratory tests for evaluation of shear failure potential at airfield asphalt pavements.