...Nikitin The model of elastoplastic medium is based on the concept of slip proposed by Batdorf and Budiansky. The conditions of slip on a slip plane take into account “the local loading criterion”. Under some assumptions we succeeded in integrating the plastic shears over all possible slip planes...

...I. Nikitin The model of elastoviscoplastic medium is based on the concept of slip proposed by Batdorf and Budiansky. The conditions of slip on a slip plane take into account the dependence of tangential stresses on slip velocity. But when the viscosity is low, they are almost similar to the dry...