• Levenberg, Eyal

Abstract

The behaviour under load of asphalt concrete (AC) was viewed as additively separable into viscoelastic and viscoplastic components, and the study focused on modelling the pre-peak response of the viscoelastic part under constant temperature conditions. Non-linear viscoelastic behaviour was first exposed in several test modes, and a constitutive theory was subsequently offered – potentially capable of capturing and reproducing the observations. The modelling was based on replacing applied stresses in the linear convolution formulation with effective stresses; it included a mechanism for simulating the following effects: (i) short-lasting damage, (ii) long-lasting damage, (iii) stiffening under compressive conditions and (iv) healing during recovery intervals. As an initial validation effort, the model’s reproducibility was assessed by calibration to a uniaxial compression experiment consisting of both small and medium strain levels. Next, the calibrated model was employed to forecast small-strain behaviour in a standard complex modulus test. The simulated results qualitatively agree with recently reported findings that challenge the existence of a linear viscoelastic domain for AC. <br/>

Topics

• theory
• experiment
• viscoelasticity
• complex modulus