Universitätsbibliothek
Weimar Open Access

Artem Semenov, B. E. Melnikov

• At the present time there is no a generally accepted theory of visco-plasticity which is applicable for a wide class of materials and arbitrary paths of loading. The multimodel approach, based on the creation of hierarchical sequence of the models, is the most rational. The developed library of elasto-visco-plastic models includes both simplest and sophistic models demanding numerous experimentalAt the present time there is no a generally accepted theory of visco-plasticity which is applicable for a wide class of materials and arbitrary paths of loading. The multimodel approach, based on the creation of hierarchical sequence of the models, is the most rational. The developed library of elasto-visco-plastic models includes both simplest and sophistic models demanding numerous experimental data. A unified general form of constitutive equations for all used elasto-visco-plastic models are presented based upon the concept of tensorial internal state variables. It permits to use unified algorithm of boundary tasks solution for different variants of material models. The developed selection criteria system generates the necessary conditions and provides the choice of the simplest variant of theory sufficient for correct problem solution. Formulation of the selection criteria system is based on peculiarities of viscoplastic materials behavior for the wide range thermomechanical loading and numerous computational experiments with structures different complexity levels. A set of effective schemes of integration stress-strain relations and non-linear finite element system solution are discussed for the considered class of material models. Application possibility of different material models is studied both for material element and for complicated structures. Application of the multimodel approach in numerical computations has demonstrated possibility of reliable prediction of stress-strain response under wide variety of combined loading.…