A strain-based failure criterion for pillar stability analysis

Gaede, Oliver, Schrank, Christoph, Canbulat, Ismet, & Karrech, Ali (2014) A strain-based failure criterion for pillar stability analysis. In Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference, The Australasian Institute of Mining and Metallurgy, Sydney,NSW, pp. 393-398.

View at publisher


Strain-based failure criteria have several advantages over stress-based failure criteria: they can account for elastic and inelastic strains, they utilise direct, observables effects instead of inferred effects (strain gauges vs. stress estimates), and model complete stress-strain curves including pre-peak, non-linear elasticity and post-peak strain weakening. In this study, a strain-based failure criterion derived from thermodynamic first principles utilising the concepts of continuum damage mechanics is presented. Furthermore, implementation of this failure criterion into a finite-element simulation is demonstrated and applied to the stability of underground mining coal pillars.

In numerical studies, pillar strength is usually expressed in terms of critical stresses or stress-based failure criteria where scaling with pillar width and height is common. Previous publications have employed the finite-element method for pillar stability analysis using stress-based failure criterion such as Mohr-Coulomb and Hoek-Brown or stress-based scalar damage models.

A novel constitutive material model, which takes into consideration anisotropy as well as elastic strain and damage as state variables has been developed and is presented in this paper. The damage threshold and its evolution are strain-controlled, and coupling of the state variables is achieved through the damage-induced degradation of the elasticity tensor. This material model is implemented into the finite-element software ABAQUS and can be applied to 3D problems.

Initial results show that this new material model is capable of describing the non-linear behaviour of geomaterials commonly observed before peak strength is reached as well as post-peak strain softening. Furthermore, it is demonstrated that the model can account for directional dependency of failure behaviour (i.e. anisotropy) and has the potential to be expanded to environmental controls like temperature or moisture.

Impact and interest:

Citation counts are sourced monthly from Scopus and Web of Science® citation databases.

These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles published in 1996 onwards, and Web of Science® generally from 1980 onwards.

Citations counts from the Google Scholar™ indexing service can be viewed at the linked Google Scholar™ search.

Full-text downloads:

65 since deposited on 20 Jan 2015
31 in the past twelve months

Full-text downloads displays the total number of times this work’s files (e.g., a PDF) have been downloaded from QUT ePrints as well as the number of downloads in the previous 365 days. The count includes downloads for all files if a work has more than one.

ID Code: 80221
Item Type: Conference Paper
Refereed: Yes
Keywords: Geomechanics, Pillar Stability, Brittle Failure, Finite Element Method, Constitutive Modelling, Non-Equilibrium Thermodynamics
ISBN: 978-1-925100-17-4
Subjects: Australian and New Zealand Standard Research Classification > ENGINEERING (090000) > RESOURCES ENGINEERING AND EXTRACTIVE METALLURGY (091400) > Geomechanics and Resources Geotechnical Engineering (091402)
Australian and New Zealand Standard Research Classification > ENGINEERING (090000) > RESOURCES ENGINEERING AND EXTRACTIVE METALLURGY (091400) > Mining Engineering (091405)
Divisions: Current > Schools > School of Earth, Environmental & Biological Sciences
Current > QUT Faculties and Divisions > Science & Engineering Faculty
Copyright Owner: Copyright 2014 [please consult the author]
Deposited On: 20 Jan 2015 03:48
Last Modified: 05 May 2015 03:20

Export: EndNote | Dublin Core | BibTeX

Repository Staff Only: item control page