Multiscale plasticity of geomaterials predicted via constrained optimization‐based granular micromechanics

Abstract

A general framework to derive nonlinear elastic and elastoplastic material models from granular micromechanics is proposed, where a constraint‐based variational structure is introduced to classical grain contact‐based homogenization methods of hyperelasticity. Like the classical hyperelastic methods, reference solutions for closed‐form hyperelastic material models are analytically derived from the grain‐scale contact mechanics. However, unlike prior methods, the proposed homogenization framework defines closed‐form hyperelastoplastic material models that extend multiscale variational methods to granular plasticity. The proposed framework is used to develop novel granular micromechanics‐based macroscopic models for a Mises type solid, Drucker–Prager type plasticity, and grain‐contact cohesive‐debonding with a deviatorically and volumetrically coupled nonlinearly elastic response. Macroscopic plastic parameters and yield criteria are explicitly related to their microscale counterparts, for example, the friction coefficient governing intergranular slip. Numerical examples and comparison to measurements from the literature, including triaxial compaction of concrete, are provided to investigate model predictions and demonstrate calibration to experimental data.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jan 12, 2022
Source ID
10.1002/nag.3320

Entities

People

  • Anil Misra
  • Eric C. Bryant
  • K.C. Bennett
  • Nathan Miller

Organizations

  • Los Alamos National Laboratory
  • United States Department of Defense
  • United States Department of Energy
  • University of Kansas

Tags

Fields of Study

  • Engineering

Readers

  • Calculus or Mathematical Analysis
  • Materials Science (Mechanical Engineering).
  • Mechanical Engineering/Mechanics of Materials.