ESTUDO NUMÉRICO DE UM PAVIMENTO DE CONCRETO ASFÁLTICO CONSIDERANDO REVESTIMENTO VISCOELÁSTICO OU ELÁSTICO-LINEAR

Abstract

The mechanical behavior of an asphalt pavement subjected to a time-varying load of a semi-sinusoidal type is presented in this paper. The pavement consists of two layers: an asphalt overlay and a granular base, supported by a subgrade. The numerical model of pavement and subgrade is implemented using the Finite Element Method through the commercial software ANSYS. A 2D-quadrilateral element (Plane183), defined by eight nodes and two degrees of translational freedom: u_x and u_y at each node, is used in the discretization of the soil-pavement system, employing axisymmetric and geometric symmetry concepts. The pavement overlay is considered as viscoelastic-linear material, modeled using the Prony series, or as linear-elastic by Resilience Modulus (MR). In both models, the base and subgrade are assumed to be linear-elastics. Thermal effects are not considered in simulations. These numerical models allow demonstrating how dynamic loading affects the vertical and horizontal stresses and vertical displacements of the pavement. The vertical displacement obtained by models are compared and validated with the scientific literature. The numerical results also demonstrate the capability of the viscoelastic model to predict the alternation and phase shift of the normal stresses experienced throughout the thickness of the asphalt overlay which cannot be evaluated by MR.