The Experts below are selected from a list of 282 Experts worldwide ranked by ideXlab platform
Javier Oliver - One of the best experts on this subject based on the ideXlab platform.
-
continuum approach to material failure in strong Discontinuity settings
Computer Methods in Applied Mechanics and Engineering, 2004Co-Authors: Javier Oliver, Alfredo Edmundo HuespeAbstract:The paper focuses the numerical modelling of material failure in a strong Discontinuity setting using a continuum format. Displacement discontinuities, like fractures, cracks, slip lines, etc., are modelled in a strong Discontinuity approach, enriched by a transition from weak to strong discontinuities to get an appropriate representation of the fracture process zone. The introduction of the strong Discontinuity kinematics automatically projects any standard dissipative constitutive model, equipped with strain softening, into a discrete traction–separation law that is fulfilled at the Discontinuity interface. Numerical issues like a global Discontinuity tracking algorithm via a heat conduction-like problem are also presented. Some representative numerical simulations illustrate the performance of the presented approach.
-
strong discontinuities and continuum plasticity models the strong Discontinuity approach
International Journal of Plasticity, 1999Co-Authors: Javier Oliver, Miguel Cervera, Osvaldo L ManzoliAbstract:The paper presents the Strong Discontinuity Approach for the analysis and simulation of strong discontinuities in solids using continuum plasticity models. Kinematics of weak and strong discontinuities are discussed, and a regularized kinematic state of Discontinuity is proposed as a mean to model the formation of a strong Discontinuity as the collapsed state of a weak Discontinuity (with a characteristic bandwidth) induced by a bifurcation of the stress–strain field, which propagates in the solid domain. The analysis of the conditions to induce the bifurcation provides a critical value for the bandwidth at the onset of the weak Discontinuity and the direction of propagation. Then a variable bandwidth model is proposed to characterize the transition between the weak and strong Discontinuity regimes. Several aspects related to the continuum and, their associated, discrete constitutive equations, the expended power in the formation of the Discontinuity and relevant computational details related to the finite element simulations are also discussed. Finally, some representative numerical simulations are shown to illustrate the proposed approach.
Osvaldo L Manzoli - One of the best experts on this subject based on the ideXlab platform.
-
strong discontinuities and continuum plasticity models the strong Discontinuity approach
International Journal of Plasticity, 1999Co-Authors: Javier Oliver, Miguel Cervera, Osvaldo L ManzoliAbstract:The paper presents the Strong Discontinuity Approach for the analysis and simulation of strong discontinuities in solids using continuum plasticity models. Kinematics of weak and strong discontinuities are discussed, and a regularized kinematic state of Discontinuity is proposed as a mean to model the formation of a strong Discontinuity as the collapsed state of a weak Discontinuity (with a characteristic bandwidth) induced by a bifurcation of the stress–strain field, which propagates in the solid domain. The analysis of the conditions to induce the bifurcation provides a critical value for the bandwidth at the onset of the weak Discontinuity and the direction of propagation. Then a variable bandwidth model is proposed to characterize the transition between the weak and strong Discontinuity regimes. Several aspects related to the continuum and, their associated, discrete constitutive equations, the expended power in the formation of the Discontinuity and relevant computational details related to the finite element simulations are also discussed. Finally, some representative numerical simulations are shown to illustrate the proposed approach.
Yang Mingcheng - One of the best experts on this subject based on the ideXlab platform.
-
the stress Discontinuity line on the slip line field theory for geo technical materials
Journal of Ningxia University, 2002Co-Authors: Yang MingchengAbstract:The problem about stress Discontinuity often exists when the limit load is solved using the slip line method or the lower boundary method of limit analysis.The stress Discontinuity is expressed using the stress Discontinuity line in the slip line field.The stress Discontinuity line is not stress character line based on the characters of stress character line.Therefore, the stress condition, stress Discontinuity value position of the stress Discontinuity line on the slip line field theory for geo-technical materials is clearly given in this paper based on the analytical expression of non-characteristic line stress boundary condition.Thus,the solving such as the limit load of acute wedge becomes simpler and more convenient.
Alfredo Edmundo Huespe - One of the best experts on this subject based on the ideXlab platform.
-
continuum approach to material failure in strong Discontinuity settings
Computer Methods in Applied Mechanics and Engineering, 2004Co-Authors: Javier Oliver, Alfredo Edmundo HuespeAbstract:The paper focuses the numerical modelling of material failure in a strong Discontinuity setting using a continuum format. Displacement discontinuities, like fractures, cracks, slip lines, etc., are modelled in a strong Discontinuity approach, enriched by a transition from weak to strong discontinuities to get an appropriate representation of the fracture process zone. The introduction of the strong Discontinuity kinematics automatically projects any standard dissipative constitutive model, equipped with strain softening, into a discrete traction–separation law that is fulfilled at the Discontinuity interface. Numerical issues like a global Discontinuity tracking algorithm via a heat conduction-like problem are also presented. Some representative numerical simulations illustrate the performance of the presented approach.
J. Oliver - One of the best experts on this subject based on the ideXlab platform.
-
On the discrete constitutive models induced by strong Discontinuity kinematics and continuum constitutive equations
International Journal of Solids and Structures, 2000Co-Authors: J. OliverAbstract:On the basis of continuum constitutive models (stress vs. strain), the introduction of strong Discontinuity kinematics (considering jumps in the displacement fields across a Discontinuity interface) induces projected discrete constitutive models (traction-displacement jumps) in a consistent manner. Therefore, this projection provides possible links between the classical continuum strain-localization analysis and the non-linear (decohesive) fracture mechanics techniques. The strong Discontinuity analysis shows that (bandwidth based) regularization of the hardening/softening parameter is the crucial modification to be done on the continuum model to achieve such a projection, and it also provides the strong Discontinuity conditions that set restrictions on the stress state compatible with bifurcations in a strong Discontinuity format. The methodology is illustrated on the basis of two classical families of non-linear constitutive models (scalar continuum damage and elasto-plasticity) for which the corresponding discrete constitutive models and the strong Discontinuity conditions are derived.
