In this paper, an elastoplastic constitutive model is presented for predicting sandy soil behavior under monotonic and cyclic loadings. The model is based on the CJS3 model that takes into account deviatoric and isotropic mechanisms of plasticity. The flow rule in deviatoric mechanism is non-associated and a kinematic hardening law controls the evolution of the yield surface. In the present s...

We consider rate-independent models of static and quasistatic plasticity with hardening. These models are usually stated in terms of variational inequalities of the first or second kind, for the primal and dual formulations, respectively. In the static case, the dual variational inequality can be interpreted as the necessary and sufficient optimality conditions for an underlying optimization pr...

In this paper, an elastoplastic constitutive model is presented for predicting sandy soil behavior under monotonic and cyclic loadings. The model is based on the CJS3 model that takes into account deviatoric and isotropic mechanisms of plasticity. The flow rule in deviatoric mechanism is non-associated and a kinematic hardening law controls the evolution of the &#10yield surface. In the present...

this paper is concerned with investigation of vertical impedance function of a surface rigid circular foundation resting on a semi-infinite transversely isotropic alluvium. to this end, the equations of motion in cylindrical coordinate system, which because of axissymmetry are two coupled equations, are converted into one partial differential equation using a method of potential function. the g...

In this work, the initial anisotropy and its evolution with strain, hardening and rupture of DC04 mild steel are characterized by using (i) a phenomenological constitutive model composed by the non-quadratic Yld2004-18p yield criterion combined with an isotropic hardening law and (ii) a macroscopic rupture criterion. For this purpose, an inverse methodology of material parameters identification...

This study investigates the effect of material parameters of the Gurson-Tvergaard-Needleman (GTN) model on the failure prediction of cellular structures. The effect of elastic modulus, calibration parameter of GTN model, isotropic hardening, fracture strain, and strut diameter on the load-displacement curve of a lattice structure fabricated by Selective Laser Melting (SLM) has been studied by u...

The question of ‘generalization’ to finite strains of the constitutive relations of infinitesimal strain theory of elasticity, and classical elasto-plasticity with isotropic and kinematic hardening, is critically examined. Simple generalizations, which lead to physically plausible material behaviour, are presented. The current controversies surrounding (i) the choice of stress-rate in the above...

Hardening plasticity has a long history in constitutive modelling, with many applications in geomechanics. Mathematical models of non-hardening plasticity involve the definition of a single stationary yield surface in stress-space. Examples include the conventional models of elasto-plasticity, often based on the yield criteria of Tresca, von Mises, and Mohr-Coulomb. Within the yield surface the...

A phenomenological theory is presented for describing the anisotropic plastic flow of orthotropic polycrystalline aluminum sheet metals under plane stress. The theory uses a stress exponent, a rate-dependent effective flow strength function, and five anisotropic material functions to specify a flowpotential, an associated flow rule of plastic strain rates, a flow rule of plastic spin, and an ev...