Modelling the Mullins effect using damage mechanics: efficiency and limitations

The present paper reports on the use of Continuum Damage Mechanics to describe the Mullins effect in elastomers. Thermodynamics of rubber-like hyperelastic materials with isotropic damage is considered. Since it is demonstrated that stress-softening is not a strictly speaking damage phenomenon, the limitations of the approach are highlighted. Moreover, connections with two-network-based constitutive models proposed by other authors are exhibited through the choice of both the damage criterion and the measure of deformation. It is shown that the present model agrees qualitatively well with experiments except for the strain-hardening phenomenon. Finally, the numerical implementation highlights the influence of loading paths on material response, that proves the importance of considering the Mullins effect in industrial design.