Constitutive modeling of viscoelastic materials with damage – computational aspects Original Research Article

The finite element implementation of a constitutive model for viscoelastic materials with damage is presented. The material model, originally developed in [S.̧ Özüpek, E.B. Becker, Constitutive equations for solid propellants, J. Engrg. Matls. Tech. 199 (1997) 125–132] has been modified to allow an efficient numerical implementation in a finite element code. A step-by-step discussion of the calibration of the material coefficients is provided, including the calibrations of the damage and cyclic loading functions. The new formulation is illustrated with representative examples for pressurization of a solid propellant rocket motor.