Proposta de modelo constitutivo viscoelástico não-linear para materiais asfálticos em regime de grandes deformações

Abstract

In some cases, asphalt materials dissipate more energy than the amount predicted by the linear (infinitesimal) theory of vis-coelasticity, when subject to large deformations, even when cracks are not observed. Thus, finite deformation viscoelastic constitutive models are demanded. It is believed that complex physical phenomena occurring in a smaller scale in fact govern the process of energy dissipation in these materials. In this work two possible mechanisms are studied: i) energy dissipation due to pre-existent internal boundaries (voids); and ii) material nonlinear behavior due to the rearrangements of the polymer chains during the process of defor-mation. Based on the results, a finite deformation viscoelastic constitutive model is proposed. Comparisons with experimental data are shown to validate the proposed model.