69 巻 (2013) 2 号 p. I_255-I_266
This paper aims to develop a finite strain anisotropic elasto-plastic constitutive model for frictional materials and its stress calculation algorithm based on the return-mapping scheme. The nonlinear rotational plastic hardening is incorporated into the model in a physically and theoretically reasonable way by introducing the dual multiplicative decompositions of the deformation gradient tensor. In addition to the usual multiplicative decomposition into elastic and plastic parts, the plastic part is decomposed further into an energetic part and a dissipative part. The energetic part leads to a tensorial internal variable related to the rotational plastic hardening. The Cam-clay plasticity model is adopted as a specific constitutive model relevant to frictional materials. Fundamental behavior of the proposed model is demonstrated through several numerical examples.