From micro scale to boundary value problem: using a micromechanically based model

Hao Xiong, François Nicot, Zhenyu Yin

Research output: Journal article publicationJournal articleAcademic researchpeer-review

12 Citations (Scopus)

Abstract

A 3D multi-scale approach is presented to investigate the mechanical behavior of a macroscopic specimen consisting of a granular assembly, as a boundary value problem. The core of this approach is a multi-scale coupling, wherein the finite element method is used to solve a boundary value problem and a micromechanically based model is employed as constitutive relationship used at a representative volume element scale. This approach provides a convenient way to link the macroscopic observations with intrinsic microscopic mechanisms. The plane strain triaxial loading condition is selected to simulate the occurrence of strain localization. A series of tests are performed, wherein distinct failure patterns are observed and analyzed. A system of shear band naturally appears in a homogeneous setting specimen. By defining the shear band area, microstructural mechanisms are separately investigated inside and outside the shear band. The normalized second-order work introduced as an indicator of instability occurrence is analyzed not only on the macroscale but also on the micro scale.

Original languageEnglish
Pages (from-to)1307-1323
Number of pages17
JournalActa Geotechnica
Volume14
Issue number5
DOIs
Publication statusPublished - 1 Oct 2019

Keywords

  • FEM
  • Granular materials
  • Mesoscopic scale
  • Micromechanics
  • Multi-scale approach
  • Second-order work
  • Shear band
  • Strain localization

ASJC Scopus subject areas

  • Geotechnical Engineering and Engineering Geology
  • Earth and Planetary Sciences (miscellaneous)

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