We study elasto-plastic deformations of unidirectional fiber reinforced polymeric composites (UFPCs) with fibers assumed to deform elastically and the matrix elasto-plastically. The matrix’s and hence composite’s plastic deformations are analyzed by using both the pressure-independent von Mises yield surface and the pressure-dependent Drucker–Prager yield surface and the associated flow rules. ...

It is a highly nonlinear problem of 3-D elastoplastic contact with friction. To obtain the key information about the real size, displacement and traction in contact zone, the elements in contact and plastic zone should be subdivided. However, the increase of degrees of freedom is limited by the problem-solving scale when traditional BEM is used, for a larger memory size is required and the solu...

Chalk is the constituent material of numerous oil reservoirs in North Sea. The mechanical behaviour of a saturated chalk has been largely studied. However, different aspects of its behaviour are not yet well understood: material characteristics depend on the saturating fluids and chalk response is timedependent. This paper proposes the PASACHALK numerical model: an elasto-plastic constitutive l...

Non-associative elasto-plasticity is the working model of plasticity for soil and rock mechanics. Yet, it is usually viewed as non-variational. In this work, we prove a contrario the existence of a variational evolution for such a model under a natural capping assumption on the hydrostatic stresses and a less natural mollification of the stress admissibility constraint. The obtained elasto-plas...

We use considerations of energy balance and dissipation to derive a self-consistent version of the shear-transformation-zone (STZ) theory of plastic deformation in amorphous solids. The theory is generalized to include arbitrary spatial orientations of STZs. Continuum equations for elasto-plastic material and their energy balance properties are discussed.

In this paper the application of the mesh-free method (MFM) for the elasto-plastic analysis of reinforced soils is studied for the first time. The applied mesh-free method is called the radial point interpolation method (RPIM). In MFM, unlike the finite element method (FEM), there is no need of mesh in the traditional sense, and the shape functions are based on nodes. In the present study the r...

The stress integration procedure proposed by Eterovic and Bathe [Inr. J. numer. Merh. Engng 30, 1099-l 114 (1990).] is studied in detail. The elasto-plasticity formulation is based on the use of the total logarithmic strains and Cauchy stresses, and the Euler backward method of time integration. The accuracy of the procedure is assessed in the solution of various analysis problems and is compar...