Fracture Toughness for Microcracking in a Viscoelastic Particulate Composite

Abstract

Fracture toughness for microcracking in a viscoelastic particulate composite is derived theoretically from the relationship between a continuum damage model and a micromechanical model. The continuum model presented by Park et al. and the micromechanical model presented by Schapery, which account for viscoelasticity and growing damage, are reviewed and compared in this paper. The condition for local microcrack growth is linked to the evolution law for damage growth in the homogenized continuum. Local microcrack growth is governed by an energy-based fracture criterion. Damage growth in the continuum is described by a phenomenological evolution law determined from an experiment. The resulting fracture toughness for asphalt concrete decreases rapidly with loading duration.