Evaluation of the propensity of strain burst in brittle granite based on post-peak energy analysis
Files
(Published version)
Date
2021
Authors
Akdag, S.
Karakus, M.
Nguyen, G.
Taheri, A.
Bruning, T.
Editors
Advisors
Journal Title
Journal ISSN
Volume Title
Type:
Journal article
Citation
Underground Space, 2021; 6(1):1-11
Statement of Responsibility
Selahattin Akdag, Murat Karakus, Giang D. Nguyen, Abbas Taheri, Thomas Bruning
Conference Name
Abstract
The increasing demand for resources and depletion of near ground mineral resources caused deeper mining operations under highstress rock mass conditions. As a result of this, strain burst, which is the sudden release of stored strain energy in the surrounding rock mass, has become more prevalent and created a considerable threat to workers and construction equipment. It is, therefore, imperative to understand how strain burst mechanism and stored excess strain energy are affected due to the high confinement in deep underground conditions. For this purpose, post-peak energy distributions for brittle rocks were investigated using a newly developed energy calculation method associated with acoustic emission (AE). A series of quasi-static uniaxial and triaxial compression tests controlled by the circumferential expansion was conducted. Snap-back behaviour known as Class-II behaviour associated with energy evolution and the material response under self-sustaining failure were analysed on granites under a wide range of confining pressures (0–60 MPa). The experimental results underline that the energy evolution characteristics are strongly linked to confinement. Stored elastic strain energy (dUE), energy consumed by dominating cohesion weakening (dUCW) and energy dissipated during mobilisation of frictional failure (dUFM) showed a rising trend as increasing the confining pressure. An intrinsic ejection velocity was proposed to express the propensity of strain burst that was purely determined by the excess strain energy released from Class II rock.
School/Discipline
Dissertation Note
Provenance
Description
Available online 11 October 2019
Access Status
Rights
© 2019 Tongji University and Tongji University Press. Production and hosting by Elsevier B.V. on behalf of Owner. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).