Novel measuring approach for damage of viscoelastic material (Part II): Experiment and numerical calculation

The numerical solution procedures for viscoelastic material subjected to deformation and mechanical damage were concerned. The analyses were based upon the constitutive model of viscoelastic material with damage derived from the elasticity recovery correspondence principle and Lemaitre-Chaboche's damage model. The uniaxial tensile tests for specimens made of polymeric materials were carried out under different strain rates at room temperature, and the stress vs. strain curves were simulated by the constitutive model of viscoelastic material without damage. The results show that the stresses predicted by the model fit with experimental stresses moderately even if damage is not considered when the strain is smaller than a certain strain threshold. But when the strain exceeds this threshold, the damage parameter should be introduced into the constitutive model. It is verified that the constitutive model with damage proposed can more accurately estimate the stress response of a class of viscoelastic particle-reinforced composite, such as solid propellent, than the constitutive model without damage.