https://cea.hal.science/cea-02339301Kebiri, S.S.KebiriCEA-DES (ex-DEN) - CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) - CEA - Commissariat à l'énergie atomique et aux énergies alternativesMaitournam, H.H.MaitournamIMSIA - UMR 9219 - Institut des Sciences de la mécanique et Applications industrielles - CEA - Commissariat à l'énergie atomique et aux énergies alternatives - ENSTA Paris - École Nationale Supérieure de Techniques Avancées - Université Paris-Saclay - CNRS - Centre National de la Recherche Scientifique - EDF R&D - EDF R&D - EDF - EDFBourgeois, M.M.BourgeoisCEA-DES (ex-DEN) - CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) - CEA - Commissariat à l'énergie atomique et aux énergies alternativesDi Paola, F.F.Di PaolaISAC - Istituto di Scienze dell'Atmosfera e del Clima - CNR - National Research Council of Italy | Consiglio Nazionale delle RicercheDuctile fracture modelling using local approaches, application to steel welded joints in nuclear componentsHAL CCSD2018Ductile fracturemodelling[PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex][PHYS.NUCL] Physics [physics]/Nuclear Theory [nucl-th]CADARACHE, Bibliothèque2019-10-30 13:34:532023-06-16 17:18:062019-10-30 13:34:53enConference papers1The simulation of crack propagation in ductile materials using the finite element method requires appropriate models for describing the nucleation, growth and coalescence of voids in a robust way. Local models, such as Rousselier and Gurson-Tvergaard-Needleman are now available in the finite element softwares as Cast3m [3]. A large number of models of this kind can be found in the literature, but they suffer from numerical drawbacks. First, they often show a marked mesh dependency of the solution. Second, volumetric locking of the elements is common in elastoplastic damage models in near-incompressible conditions. These two major issues must be solved in order to insure the robustness of such approaches. Our goal is to propose a model which be able to handle these two problems. The mesh dependency can solved by using regularization techniques, such as implicit gradient enrichment of an internal variable [1]. The locking can be treated, either using selective integration techniques, or a mixed formulation [2], which adds the volume variation as a new variable in addition to the displacement.The proposed models, based on the existing Rousselier and GTN models in Cast3m [3], address both issues using an implicit-enriched gradient of damage, and include a mixed formulation in the local models to ensure the desired robustness. In this presentation, the new models and the implementation of the new models are first presented. In a second part, simulations of crack propagation using the proposed models for axisymmetric and compact-tensile specimens in 2D using the Cast3m finite element software [3] are used to illustrate the relevancy of the approach.