Page 195 - MODELING OF ASPHALT CONCRETE

VEPCD Modeling of Asphalt Concr ete with Gr owing Damage 173

FIGURE 7-6 Stress-pseudosstrain behavior of asphalt concrete in (a) controlled-stress cyclic
test and (b) constant-strain-rate monotonic test (different symbols represent different strain
rates).

In studying the constitutive behavior of a material with damage, two general
approaches are usually considered: a micromechanical approach and a continuum
approach. Initiated by Kachanov (1958), continuum damage mechanics has been
extensively investigated and applied to various engineering materials by many
researchers (e.g., Lemaitre 1984; Kachanov 1986; Krajcinovic 1984, 1989; Bazant 1986). In
continuum damage mechanics, the damaged body can be viewed as a homogeneous
continuum on a macroscopic scale, and the influence of damage is typically reflected in
terms of reduction in stiffness or strength of the material. The state of damage can be