Gene

Quantum mechanics

Composite number

Engineering

Materials science

Robustness (evolution)

Biochemistry

Constitutive equation

Viscoplasticity

Polymer

Physics

Finite element method

Nonlinear system

Composite material

Structural engineering

Chemistry

Mechanics

Strain rate

Journal of Aerospace Engineering

For polymer matrix composites subjected to large strain rates, it is important to correctly characterize the nonlinear and strain-rate dependent response of polymers. Viscoplastic constitutive material models have been developed to account for the effects of hydrostatic effects and inelastic strains in polymer materials. The effective implementation of such viscoplastic models is important for development of composite models geared toward practical applications. Goldberg’s polymer model numerical implementation into a commercial finite-element code constitutes the main objective of this paper. Special attention is given to the use of effective algorithms for solving the model nonlinear rate dependent viscoplastic equations. Existent experimental data are used to verify the accuracy and robustness of the computational polymer model. A phenomenological fiber model and a simplified iso-strain mixture theory used to obtain the resultant stresses in the composite by averaging the stresses of the individual constituents are also defined. The validation of the simplified mixture theory for the composite model will be presented later on.

Numerical Implementation of Polymer Viscoplastic Equations for High Strain-Rate Composite Models