Abstract
For the analysis of elastic plastic cyclic behavior of structural steels, a new model is proposed modifying the Prager's kinematic hardening model. During the plastic flow, this model behaves as the kinematic hardening model or as the isotropic-kinematic hardening one. In the isotropic-kinematic hardening range, the combination parameter β is introduced. The isotropic hardening and the kinematic hardening behavior occur in the ratio of β and (1-β), respectively. β=1 corresponds to purely isotropic hardening and β=0 corresponds to purely kinematic hardening. Cyclic hardening behavior is observed at the first few cycles due to the expansion and translation of the yield surface and after that steady state behavior is observed due to the translation of the yield surface, under the cyclic straining with constant strain amplitudes. Generalized constitutive relationship of the model is obtained. Considering the Bauschinger's effect of the material, a series model is also proposed. This model consists of a collection of isotropic-kinematic hardening elements having different mechanical behaviors. Comparing with the experimental restlts obtained by Dr. Tanabashi et al., uniaxial stress-strain behavior by this model agrees fairly well with the experimental results.
