Time-dependent Drucker-Prager-Cap model coupled with PANDA (Pavement Analysis Using Nonlinear Damage Approach) to predict rutting performance of flexible pavements

Abstract An extended Drucker-Prager-Cap-Creep (D-P-Cap-Creep) constitutive relationship is coupled with the PANDA (Pavement Analysis using Nonlinear Damage Approach) model to predict rutting in granular and asphalt layers of flexible airfield pavements, respectively. The presented model treats the pavement structure as a system and predicts rutting performance as the summation of permanent deformation in the subgrade, subbase, base, and asphalt layers. In addition to capturing the effects of densification and shear on permanent deformation with the D-P-Cap model, a creep law is defined to capture time- and rate-dependent behavior of granular layers and the subgrade. Simulation results of D-P-Cap-Creep constitutive relationship in conjunction with PANDA are validated against test sections of Construction Cycle 3 (CC-3) at the National Airport Pavement Test Facility (NAPTF). Presented results demonstrate that incorporation of time hardening Creep law to D-P-Cap model resulted in reduction in deviation between field measurements and model predictions. It is argued that the D-P-Cap-Creep constitutive relationship may have a more pronounce effect on rutting evolution of flexible pavements with moist subgrades with high clay contents.