Evolution of Cracks at the Edge of a Gas-Bearing Coal Seam under Stationary Mining
- Authors: Feldman E.P.1, Kalugina N.A.1, Chesnokova O.V.1
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Affiliations:
- Institute of Physics of Mining Processes of the National Academy of Sciences of Ukraine
- Issue: Vol 60, No 3 (2019)
- Pages: 560-568
- Section: Article
- URL: https://journals.rcsi.science/0021-8944/article/view/161579
- DOI: https://doi.org/10.1134/S0021894419030192
- ID: 161579
Cite item
Abstract
In this paper, we consider the conditions under which the gas enclosed in a main crack located at the edge of a coal or rock formation can produce fracture of the formation. Kinetic theory is developed for two competing physical processes: formation unloading due to rock pressure and gas filtration from the crack cavity into the surrounding rock. The first process promotes fracture, and the second leads to a decrease in the gas pressure causing the fracture. The evolution of the crack is determined by the ratio of the rates of these processes. It is found that a modified Griffith’s criterion is a necessary but not sufficient condition for fracture. For formation fracturing, it is also necessary that the ratio of the unloading rate to the filtration rate exceed a certain threshold value.
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About the authors
E. P. Feldman
Institute of Physics of Mining Processes of the National Academy of Sciences of Ukraine
Author for correspondence.
Email: edward.feldman.40@gmail.com
Ukraine, Dnepr, 49600
N. A. Kalugina
Institute of Physics of Mining Processes of the National Academy of Sciences of Ukraine
Email: edward.feldman.40@gmail.com
Ukraine, Dnepr, 49600
O. V. Chesnokova
Institute of Physics of Mining Processes of the National Academy of Sciences of Ukraine
Email: edward.feldman.40@gmail.com
Ukraine, Dnepr, 49600