A finite-strain Cam-clay model in the framework of multiplicative elasto-plasticity

The present work discusses a finite-strain plasticity model for soft clays. To motivate such a model, the infinitesimal-strain assumption is shown to be inadequate for the constitutive description of soft clays. Hence, assumi ng the multiplicative elasto-plastic decomposition of the deformation gradi ent, a finite-strain Cam-clay model is presented. In particular, with respe ct to the original Cam-clay formulation, this model improves the descriptio n of the isotropic compression behaviour as well as of the elastic shearing response. The constitutive laws are discussed and their implications are p ointed out. The physical meaning of the model parameters is carefully addre ssed. Finally, the ability to properly match some experimental results avai lable in the literature is assessed. (C) 1998 Elsevier Science Ltd. All rig hts reserved.