Correspondence Principle for Characterization of Asphalt Concrete

In this paper, Schapery's nonlinear elastic-viscoelastic correspondence principle based on pseudostrain concept is introduced as a means of separately evaluating important mechanisms of asphalt concrete under cyclic loading, including time dependence, damage growth, and fracture healing. Earlier work by Kim and Little and the findings from this present study have demonstrated that the correspondence principle can be applied to most of the testing conditions encountered in testing of asphalt concrete. The importance of using proper analytical representation of relaxation modulus in course of calculating pseudostrain is demonstrated using the cyclic data. At the loading frequencies typically used in asphalt-concrete testing (faster than 10 Hz), the creep or relaxation data must be represented in a form that can accurately describe the short time behavior, such as the modified power law. It is concluded that the correspondence principle provides a means of more accurately modeling the damage growth and fracture healing of asphalt concrete under complex cyclic loading.