Identificação do comportamento viscoelástico não-linear e do dano em misturas asfálticas utilizando testes de varredura de tensão

Abstract

Asphaltic materials are known to have a behavior that can be approximated by the viscoelasticity theory. In these materials it is essential to separate the nonlinear viscoelastic response from the fatigue damage response. This is a complex issue, because both nonlinearity and damage have a similar effect on the material mechanical behavior. This paper presents experimental and analytical procedures for separation of the nonlinear viscoelastic response from the fatigue damage in hot asphalt mixtures (HMA). A Universal Testing Machine 25 was used to perform stress sweep tests in three different HMAs. Once all the strain values were collected for each material, a statistical analysis was used to find the maximum stress that can be applied to the material without invoking the fatigue damage response. The results showed that the transition stress is directly associated with the material properties and stiffness can be a determining factor.