The problem of quasistatic evolution in small strain associative elastoplasticity is studied in the framework of the variational theory for rate-independent processes. Existence of solutions is proved through the use of incremental variational problems in spaces of functions with bounded deformation. This provides a new approximation result for the solutions of the quasistatic evolution problem...

In this article, the optimal control of static elasto-plastic contact problems are discussed. We present regularization approaches for the nondifferentiabilities arising from contact as well as from elastoplasticity in order to apply fast Newton-type solution algorithms. To achieve an efficient algorithm, we adaptively balance the both regularization, the discretization, and the numerical error...

Abstract-The elastoplastic constitutive analysis which utilizes the model of multiplicative decomposition of the defo~ation gradient into its elastic and plastic parts has been mainly developed and applied to elastically isotropic materials, which remain isotropic during the process of plastic deformation. This paper extends the application of the model to materials that change their elastic pr...

We present a semi-implicit return mapping algorithm for integrating generic nonsmooth elastoplastic models. The semi-implicit nature of the algorithm stems from ‘‘freezing” the plastic internal variables at their previous state, followed by implicitly integrating the stresses and plastic multiplier. The plastic internal variables are incrementally updated once convergence is achieved (a posteri...

A (microscopic) static elastoplastic field theory of dislocations with moment stress is considered. The relationship between the moment stress and the Nye tensor is discussed and used for the dislocation Lagrangian. We discuss the stress field of a screw dislocation which is modified in the core region due to the appearance of moment stress.