We present a novel particle-based method for stable simulation of elasto-plastic materials. The main contribution of our method is an implicit numerical integrator, using a physically-based model, for computing particles that undergo both elastic and plastic deformations. The main advantage of our implicit integrator is that it allows the use of large time steps while still preserving stable an...

This work is devoted to the analysis of elasto-plasticity models arising in soil mechanics. Contrary to the typical models mainly used for metals, it is required here to take into account plastic dilatancy due to the sensitivity of granular materials to hydrostatic pressure. The yield criterion thus depends on the mean stress and the elasticity domain is unbounded and not invariant in the direc...

Simple and economical procedures for large-deformation elasto-plastic analysis of frames, whose members can be characterized as beams, are presented. An assumed stress approach is employed to derive the tangent stiffness of the beam, subjected in general to non-conservative type distributed loading. The beam is assumed to undergo arbitrarily large rigid rotations but small axial stretch and rel...

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...

In the context of nuclear waste disposal, the modelling of the behaviour of host rocks and soils still needs improvement. Unsaturated porous geomaterials exhibit particular behaviour when exposed to suction. Their non-linear behaviour may result from two different processes, plasticity which induces irreversible strains and damage which causes a deterioration of their elastic properties. Many e...

Abstract-In this paper, certain path-independent integrals, of relevance in the presence of cracks, in elastic and inelastic solids are considered. The hypothesized material constitutive properties include: (i) finite and infinitesimal elasticity, (ii) rate-independent incremental flow theory of elasto-plasticity, and (iii) ratesensitive behaviour including elasto-viscoplasticity and creep. In ...

Elasto fibroma dorsi is a rare tumour of the shoulder girdle that usually arises at the infra scapular area. We present a 57-year-old male with a soft tissue swelling on his right infra scapular area of 6 months duration. It was a painless lesion which caused him discomfort while sleeping. Preoperative imaging revealed bilateral tumours but the left tumour was impalpable. The surgery itself was...

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...

In this paper some analytical and numerical aspects of time-dependent models with internal variables are discussed. The focus lies on elasto/visco-plastic models of monotone type arising in the theory of inelastic behavior of materials. This class of problems includes the classical models of elasto-plasticity with hardening and viscous models of the Norton-Hoff type. We discuss the existence th...

Abstract—In this paper, an analytical simplified method for calculating elasto-plastic stresses strains of notched bodies subject to non-proportional loading paths is discussed. The method was based on the Neuber notch correction, which relates the incremental elastic and elastic-plastic strain energy densities at the notch root and the material constitutive relationship. The validity of the me...