Rutting Prediction of Flexible Pavements Using Finite Element Modeling

During the past two decades, Finite Element (FE) techniques were successfully used to simulate different pavement problems that could not be modelled using the simpler multi-layer elastic theory. In this study, a two-dimensional finite element model was developed, using ABAQUS software, in order to investigate the impact of static repeated wheel load on rutting formation and pavement response. The procedures of building a model and performing static analysis are introduced. In that model, pavement materials were presented as linear-elastic-plastic based on Drucker-Prager model. In addition, the asphalt layer was assumed to follow a viscoelastic behavior using Pellinen and Witczak model, which was adopted by NCHRP. The Falling Weight Deflectometer FWD was also proposed as an effective and practical tool for on-site pavement evaluation and field measurements, other than the laboratory tests. After insuring the model validation, the study investigated the impact of temperature, tire pressure and subgrade strength on the rut depth as a pavement response. The sensitivity analysis indicated that the rut depth increases with increasing the temperature and the tire pressure and with decreasing the subgrade strength.