A thermomechanical constitutive model for cemented granular materials with quantifiable internal variables. Part II - Validation and localization analysis

Research output: Contribution to journalArticle

Abstract

We study the mechanical failure of cemented granular materials (e.g., sandstones) using a constitutive model based on breakage mechanics for grain crushing and damage mechanics for cement fracture. The theoretical aspects of this model are presented in Part I: Tengattini et al. (2014), A thermomechanical constitutive model for cemented granular materials with quantifiable internal variables, Part I - Theory (Journal of the Mechanics and Physics of Solids, http://dx.doi.org/10.1016/j.jmps.2014.05.021). In this Part II we investigate the constitutive and structural responses of cemented granular materials through analyses of Boundary Value Problems (BVPs). The multiple failure mechanisms captured by the proposed model enable the behavior of cemented granular rocks to be well reproduced for a wide range of confining pressures. Furthermore, through comparison of the model predictions and experimental data, the micromechanical basis of the model provides improved understanding of failure mechanisms of cemented granular materials. In particular, we show that grain crushing is the predominant inelastic deformation mechanism under high pressures while cement failure is the relevant mechanism at low pressures. Over an intermediate pressure regime a mixed mode of failure mechanisms is observed. Furthermore, the micromechanical roots of the model allow the effects on localized deformation modes of various initial microstructures to be studied. The results obtained from both the constitutive responses and BVP solutions indicate that the proposed approach and model provide a promising basis for future theoretical studies on cemented granular materials. (C) 2014 Elsevier Ltd. All rights reserved.

Details

Authors
  • Arghya Das
  • Alessandro Tengattini
  • Giang D. Nguyen
  • Gioacchino Viggiani
  • Stephen Hall
  • Itai Einav
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Mechanical Engineering

Keywords

  • Cemented granular materials, Constitutive behavior, Microstructures, Energy methods, Fracture mechanisms
Original languageEnglish
Pages (from-to)382-405
JournalJournal of the Mechanics and Physics of Solids
Volume70
Publication statusPublished - 2014
Publication categoryResearch
Peer-reviewedYes