A constitutive model for finite deformation anisotropic elastoplasticity, developed within the framework of the multiplicative decomposition of the deformation gradient and of the theory of the structural tensors is discussed. The main goal of the paper is to analyze the extension of finite deformation plasticity to the case that material directions can evolve due to mechanical actions. This is obtained by considering the structural tensors as internal variables and introducing thermodynamic forces conjugated to them. The internal energy is assumed to depend on the elastic strain tensor and on the structural tensors, so that, employing Clausius-Duhem dissipation inequality, evolution equations for plastic deformation and for irreversible changes in the structural tensors are obtained that can consist of rotation of the material direction or also of the modification of the norm of the material directors. Examples show that the model can be used for studying the response of fiber materials like soft tissues, amorphous polymers, etc.
|Titolo:||MODEL OF ANISOTROPIC ELASTOPLASTICITY IN FINITE DEFORMATIONS ALLOWING FOR THE EVOLUTION OF THE SYMMETRY GROUP|
|Data di pubblicazione:||2015|
|Appare nelle tipologie:||1.1 Articolo in rivista|