This paper aims to develop a numerical multiscale homogenization method for prediction of elasto-viscoplastic properties of a high performance concrete (HPC). The homogenization procedure is separated into two-levels according to the microstructure of the HPC: the mortar or matrix level and the concrete level. The elasto-viscoplastic behavior of individual microstructural phases of the matrix a...

Using the periodic unfolding method we construct the homogenization theory for the quasistatic initial boundary value problems with internal variables, which model the deformation behavior of viscoplastic materials with a periodic microstructure. The free energy associated with models is assumed to be positive semi-definite only.

Electronic power modules devices are paramount components in the aeronautical, automotive and military applications. The solder layers are the most critical parts of the module and are usually subjected in their whole life to complex loading conditions. To improve the design task, realistic thermoelastoviscoplastic and lifetime prediction models which can describe efficiently the deformation-da...

We present a mathematical model for the description of the behavior of viscoplastic materials. The model is based on a nonlinear diierential equation of order , where is a material constant typically in the range 0 < < 1. This equation is coupled with a rst-order diierential equation. For the numerical solution of these equations, we have developed an algorithm based on a PECE-type approach.

The propagation of steady plane shock waves in metallic materials is considered. Following the constitutive framework adopted by R. J. Clifton @Shock Waves and the Mechanical Properties of Solids, edited by J. J. Burke and V. Weiss ~Syracuse University Press, Syracuse, N.Y., 1971!, p. 73# for analyzing elastic–plastic transient waves, an analytical solution of the steady state propagation of pl...

In contrast with simple liquids such as water, milk, honey, which easily flow as a continuous jet when poured from a vessel, pasty materials such as mayonnaise, mustard, ketchup, puree, etc., fall by fits and starts in a wide range of flow rates. This may, for example, be observed when ketchup or mayonnaise is pushed from a tube at a sufficient height over a plate: although surface tension effe...

This paper presents a variational formulation of viscoplastic constitutive updates for porous elastoplastic materials. The material model combines von Mises plasticity with volumetric plastic expansion as induced, e.g., by the growth of voids and defects in metals. The finite deformation theory is based on the multiplicative decomposition of the deformation gradient and an internal variable for...