Linear and nonlinear fractional hereditary constitutive laws of asphalt mixtures

Abstract

The aim of this paper is to propose a fractional viscoelastic and viscoplastic model of asphalt mixtures using experimental data of several tests such as creep and creep recovery performed at different temperatures and at different stress levels. From a best fitting procedure it is shown that both the creep one and recovery curve follow a power law model. It is shown that the suitable model for asphalt mixtures is a dashpot and a fractional element arranged in series. The proposed model is also available outside of the linear domain but in this case the parameters of the model depend on the stress level.

Keyword : fractional calculus, asphalt mixture, viscoelasticity, viscoplasticity, rheology, mechanical models, creep test