Identification of the spatial variability of stress fields in polycrystalline aggregates and application to the local approach to failure
type: Dataset
description: This thesis is a contribution to the construction of the Local Approach to fracture at the microscopic scale using polycrystalline aggregate modeling. It consists in taking into account the spatial variability of the microstructure of the material. To do this, the micromechanical modeling is carried out by finite element analysis of polycrystalline aggregates. The random stress fields (maximum principal et cleavage stress) in the material representing the spatial variability of the microstructure are then modeled by a stationary ergodic Gaussian random field. The properties of the spatial variability of these fields are identified by an identification method, e.g. periodogram method, variogram method, maximum likelihood method. The synthetic realizations of the stress fields are then simulated by a simulation method, e.g. discrete Karhunen-Loève method, circulant embedding method, spectral method, without additional finite element calculations. Finally, a Local Approach to fracture by simulation of the cleavage stress field using the simulated realizations is constructed to estimate the rupture probability of the material.
landing page: https://theses.hal.science/tel-00822107
identifier: NNT: 2012CLF22278
keyword: agregats-polycristallins
keyword: approche-locale-de-la-rupture
keyword: calculs-aux-elements-finis
keyword: champs-aleatoires-gaussiens-stationnaires
keyword: circulant-embedding-method
keyword: cleavage-stress
keyword: contrainte-de-clivage
keyword: decomposition-de-karhune-loeve
keyword: ergodicite
keyword: ergodicity
keyword: finite-element-simulation
keyword: identification
keyword: infoeu-reposemanticsdoctoralthesis
keyword: karhunen-loeve-expansion
keyword: local-approach-to-fracture
keyword: methode-circulant-embedding
keyword: periodogram
keyword: periodogramme
keyword: polycrystalline-aggregates
keyword: semi-variogram
keyword: simulation-de-realisations
keyword: simulation-of-realizations
keyword: spatial-variability
keyword: spiotherengineering-sciences-physicsother
keyword: stationary-gaussian-random-fields
keyword: theses
keyword: variabilite-spatiale
keyword: variogramme
issued: 2026-05-11T03:57:39.710609
modified: 2026-05-11T03:57:39.710614
language: fr
contact point: Organization
  fn: CCSD

test_moissonnage_selune
type: Agent

Identification of the spatial variability of stress fields in polycrystalline aggregates and application to the local approach to failure
type: Distribution
format: HTML
access URL: https://theses.hal.science/tel-00822107
issued: 2026-05-11T03:57:39.713972
modified: 2026-05-11T03:57:39.671378