Mineralized biological materials such as nacre or bone achieve remarkable combinations of stiffness and toughness by way of staggered arrangements of stiff components (nanoscale or microscale fibers or tablets) bonded by softer materials. Under applied stress these components slide on one another, generating inelastic deformations and toughness on the macroscale. This mechanism is prominent in ...

The inelastic response of materials to applied uniaxial loading is typically measured using tensile or compressive specimens of initially circular cross-section. Under deformation, this cross-section may become elliptical due to anisotropic material behaviour. An optical technique for measuring the elliptical deformation of anisotropic, homogeneous cylindrical specimens undergoing uniaxial defo...

This paper presents a new particle method in LS-DYNA for the severe deformation and failure analyses of solid mechanics problems. The new formulation is first established following a standard meshfree Galerkin approach for a solving of the partial differential equation of linear elastic problems. A smoothed displacement field is introduced to the Galerkin formulation and leads to a regularized ...

Understanding the deformation mechanisms in ceramic materials is crucial for optimizing and implementing next-generation ceramic materials in body and vehicle armor systems. One particularly powerful tool for studying deformation mechanisms is transmission electron microscopy (TEM) of impacted materials. Indentation is useful for studying deformation mechanisms, since this method offers the abi...

The microstructure of enamel like most biological tissues has a hierarchical structure which determines their mechanical behavior. However, current studies of the mechanical behavior of enamel lack a systematic investigation of these hierarchical length scales. In this study, we performed macroscopic uni-axial compression tests and the spherical indentation with different indenter radii to prob...

Variational iteration method VIM is applied to solve linear and nonlinear boundary value problems with particular significance in structural engineering and fluid mechanics. These problems are used as mathematical models in viscoelastic and inelastic flows, deformation of beams, and plate deflection theory. Comparison is made between the exact solutions and the results of the variational iterat...

This paper describes a finite element geo-process modeling software, which is able to solve multiphysics problems in the area of geo science. It is one of the first applications providing complete thermal, two-phase-flow, inelastic deformation court within one framework. As a real-life example the FEBEX THM coupling problems are described. These kind of problems are very demanding in terms of C...

Elastic and inelastic scattering of 'Li from "C have been measured at incident energies of 63 and 78.7 MeV. The experimental data were obtained over an angular range from 8„,=8' to 40'. Optical model parameters have been extracted by fitting the elastic scattering data, and deformation lengths have been obtained for the 'Li* (0.48 MeV) state and the "C~ (4.44 MeV) state. No single parameter set...

In this paper we develop the governing equations of the coupled damage-plasticity model, which is capable of representing the main mechanisms of inelastic behavior including irreversible plastic deformation, change of elastic response and the localized failure. We show in particular how such model should be implemented within the stress-based variational formulation, providing an important adva...

The impact of a two-dimensional elastic disk with a wall is numerically studied. It is clarified that the coefficient of restitution (COR) decreases with the impact velocity. The result is not consistent with the recent quasi-static theory of inelastic collisions even for very slow impact. This suggests that the elastic model cannot be used in the quasi-static limit. A new quasi-static theory o...