Analysis of axial strain in one-dimensional loading by different models

Abstract

Different phenomenological equations based on plasticity, primary creep (as a viscoplastic mechanism), secondary creep (as another viscoplastic mechanism) and different combinations of these equations are presented and used to describe the material inelastic deformation in uniaxial test. Agreement of the models with experimental results and with the theoretical concepts and physical realities is the criterion of choosing the most appropriate formulation for uniaxial test. A model is thus proposed in which plastic deformation, primary creep and secondary creep contribute to the inelastic deformation. However, it is believed that the hardening parameter is composed of plastic and primary creep parts. Accordingly, the axial plastic strain in a uniaxial test may no longer be considered as the hardening parameter. Therefore, a proportionality concept is proposed to calculate the plastic contribution of deformation.

Experimental study on mechanical properties of methane-hydrate-bearing sediments

“…In the future, more widely varied saturations, the homogeneity of hydrate distribution in sediments and the effects of compositions and microstructures of soil skeleton will be considered. Further, the formulation of plastic deformation of hydratebearing sediments referred to the model by Aryanpour and Farzaneh [42] will be explored also which can provide a basis for evaluating the possible geo-hazards in hydrate exploitation.…”

Contribution of Primary Creep in Modeling the Mechanical Behavior of Polycrystalline Ice

“…• It should be remarked that in a more general modeling scope, a permanent inelastic deformation with a time-independent nature (plastic deformation) can be considered for. polycrystalline ice similar to what has already done for other crystalline materials such as metals [16]. However, because of the fact that ice deformation is studied in a temperature range greater than 0.85T'",, where T" is the absolute melting point, plastic deformation is negligible in comparison with viscoplastic deformation.…”

Finite element analysis of elastoplastic modeling: application to one-dimensional loading of as-received and pre-strained materials

“…The elastoplastic model proposed in this paper was introduced in some previous works [11,13]. The model ability to calculate plastic deformation where the stress state is located within the interior of loading surface provided this possibility to use the proposed model as a part of a more comprehensive elastoplastic-viscoplastic modeling in the previous works.…”