Three Dimensional Finite Element Analysis of Top-Down Cracking for Asphalt Pavements

In this paper, structural performance of a flexible pavement is evaluated using the finite element analysis considering the effect of tire pressure, axle load variations of vehicles. The pavement structure is modeled as three-dimensional four-layer system using finite element software of ANSYS. The pavement model is subjected to traffic loadings to simulate truck wheel loads at three different tire inflation pressures. Results from the model are verified using in laboratory test data. Model comparisons with measured laboratory test data are in good agreement. Therefore, finite element method could be used to estimate the potential distress efficiently. Analysis results show that peak maximum shear stress are very high and locates at the same magnitude level of the shear intensity of HMA, while maximum tension stress in direction of X, Y and Z are small. Hence, shear stress is an important factor that could result in top-down cracking in asphalt pavements.