Analysis to Nonlinear Creep Behavior of Viscoelastic Materials with Structure Varieties by Means of Irreversible Thermodynamics (Ⅱ)
The so-called structure parameters are firstly introduced to indicate their influence on nonlinear viscoelastic behavior and the corresponding nonlinear evolution equation is then derived based on the linear one proposed by Biot by means of thermodynamics of irreversible process. As a worked example, the above nonlinear evolution equation is applied to a viscelastic rod of the ideal viscoelastic solid to predict its uniaxial creep behavior. Under the strain-induced anisotropic effect due to the configurationally structure changes, the originally isotropic rod gradually becomes transversely isotropic one during the creep deformation process. The final results show that (i) when the applied longitudinal stress is below a certain value, the creep strain will get towards an asymptotic value at a decreasing strain rate, and that (ii) when over this value, it will initially increase at a decreasing strain rate and then at an accelerative rate after overcoming a critical point.
Young-Jin Kim, Dong-Ho Bae and Yun-Jae Kim
G. Z. Dai et al., "Analysis to Nonlinear Creep Behavior of Viscoelastic Materials with Structure Varieties by Means of Irreversible Thermodynamics (Ⅱ) ", Key Engineering Materials, Vols. 297-300, pp. 390-396, 2005