A viscoelastic constitutive model based on nonlinear evolutionary internal variables

摘要

Based on the internal variable theory, a viscoelastic constitutive model of highly deformable continuous medium is proposed. A set of second rank tensorial internal state variables corresponding to the engineering strain is introduced and a nonlinear evolution law for these internal variables is suggested. It is found that the present model can be used to describe strain rate sensitivities of polymeric materials.