Modeling of Pavement Response Using Nonlinear Cross-Anisotropic Approach

The multi-depth deflectometer (MDD) is used to estimate flexible pavement response subjected to permitted overweight truck traffic (gross vehicle weight up to 556 kN). This study focuses on using material constitutive models to assess the most accurate and reliable pavement layer behavior. To obtain stress dependent cross-anisotropic material properties of unbound granular material and intact soils, a modified triaxial test was performed. The obtained material properties were compatible with findings of previous researches. The developed finite element program (NCPA) was used to evaluate deflections under proposed four models and to determine the best model by comparing with field measurement of MDD. As a result, the best comparisons with the measured MDD deflections were achieved when base and subgrade materials were modeled as nonlinear cross-anisotropic by reducing error range significantly.