FURSTOSS , Jean

This thesis aims at simulating the microstructural evolutions of upper mantle rocks under thermomechanical conditions representative of the Earth's lithosphere. Indeed, the mechanical behavior of these rocks controls, at first order, the rheology of the lithosphere and thus of the tectonic plates.The tools used and developed in this work are...

International audience

In this study, we investigate grain growth within pure olivine systems through numerical simulations. The level set (LS) approach within a finite element (FE) context enables modeling 3D microstructural evolutions such as grain growth. As this phenomenon is inherently a 3D mechanism, the comparison between 2D and 3D models shows differences...

In this work we present a simple and convenient method for handling tensors within computational mechanics frameworks based on the Kelvin decomposition. This methodology was set up within a crystal plasticity framework which permits, using the Kelvin base related to the crystal symmetries, to account for elastic anisotropy. The classical mixed...

Abstract. This paper presents a new mesoscopic full field approach for the modeling of microstructural evolutions and mechanical behavior of olivine aggregates. The mechanical framework is based on a reduced crystal plasticity (CP) formulation which is adapted to account for non-dislocation glide strain-accommodating mechanisms in olivine...

Le phénomène de croissance de grains peut être vu comme une migration des interfaces entre grains pilotée par la minimisation de l'énergie surfacique du réseau de joints de grains. Ces interfaces séparent deux domaines d'orientations cristallographiques différentes et possèdent une énergie par unité de surface dépendant du matériau considéré,...

International audience

We present a full field framework based on the level‐set (LS) approach, which enables to simulate grain growth in a multiphase material. Our formalism permits to take into account different types of second phases, which can be static or dynamic (i.e. evolving also by grain growth) and reproduce both transient (evolving relative grain sizes) and...

SUMMARY We investigate the effect of solute drag on the grain growth (GG) kinetics in olivine-rich rocks through full field and mean field modelling. Considering a drag force exerted by impurities on grain boundary migration allows reconciling laboratory and natural constraints on olivine GG kinetics. Solute drag is implemented in a full field...

Because olivine is the major constituent of upper mantle rocks, its mechanical properties and microstructural evolutions play an important role in the lithosphere rheology. In this study, we investigate the deformation of olivine polycrystals through a numerical framework coupling the crystal plasticity and the finite element method (CPFEM)....