ABSTRACT
Rubber-like materials were initially considered as isotropic hyperelastic materials. In an attempt to characterize rubber-like material hyperelasticity, it has been observed that special mechanical test conditions are required in order to eliminate the viscoelastic part of the material response, and during the first cycle of loading, a strain induced stress-softening, known as the Mullins effect, induces a permanent deformation and anisotropy that have to be taken into account. As far as damage is concerned, it has been considered for long, that a material should be submitted to several cycles before any stress-strain measurement, in order to eliminate the Mullins effect. Hence, a material directional based constitutive model with damage is proposed in order to fit hyperelastic behavior of rubber-like materials possibly anisotropic due to the loading history. Damage in rubber-like materials comes from two sources, one is the mullins effect which deals with a discontinuous damage and the other one is fatigue which can be represented by a continuous damage.
