Resumen de Extremal properties of endochronic plasticity, Part I: Extremal path of the constitutive equation without a yield surface
Xianghe Peng, A.R.S. Ponter
Based on the general extremal properties of time-independent inelastic materials proposed by Ponter and Martin, some extremal properties of endochronic theory of plasticity are investigated. The extremal path of an endochronic constitutive equation without using a yield surface is found, which makes plastic work act as a potential such that the deviatoric stress can be derived from its derivative with respect to plastic strain. These properties are important because they provide the possibility for the irreversible thermodynamically based constitutive equation, which is strongly history-dependent, to be applied to simplified analysis in engineering problems. Using the derived extremal properties, the principle of minimum potential energy is extended to endochronic theory of plasticity. As an example, the stress and strain field of a hinge-joint three-bar truss are analyzed.
