The unified elastic-viscosic-plastic theory of solids

In this paper, mt unified elastic-viscosic-plastic theory which can compute the change of elastic, viscosic and plastic state of each point in the bod y is proposed. The theory is based on the laws of thermodynamics and the ps eudo elastic postulate. lit the paper, the constitutive equations and varia tional principles are deduced. From which, the finite element method of bot h space and time may be easily formulated. Note that, by choosing the mater ial parameters properly, the plastic constitutive equations currently used may be given.