Characterization of airfield pavement granular layers under moving wheel loads

This paper mainly demonstrates the importance of identifying the most damaging field loading conditions in a pavement, which often require considering the effects of moving wheel loads in laboratory testing and materials characterization. To account for the combined vertical and horizontal pulsing loads imposed on a pavement element under the moving aircraft, a suite of constant stress path tests were performed on a dense graded granular base material. Six resilient modulus models developed from the test results were then used in a finite element program, GT-PAVE, to solve for the critical pavement responses of typical flexible airport pavement sections under the applied wheel loading of the Boeing 777 aircraft. Models obtained from extension stress states resulted in the most damaging field loading conditions since they produced the lowest modulus distributions throughout the granular layer. As a result, the predicted critical pavement responses increased thus causing a reduction in the pavement performance and/or service lives due to the effects of moving wheel loads.