Pershin G.D., Pshenichnaya E.G. Mechanism of Quasi-Static Fracture of Rock Volumes by a Spreading Action on the Borehole Walls

DOI: 10.18503/1995-2732-2024-22-1-13-19

Abstract

The research is aimed at developing a methodological framework for setting and solving a number of mining production problems of practical importance by analyzing the mechanism of quasi-brittle fracture of solid bodies. At the same time, the authors solved the problem of determining the energy and force conditions of fracture of the accepted model in the shape of a hollow cylinder loaded with internal pressure as part of the force approach of quasi-static theory. The developed calculation scheme was built as a three-stage one, when at the first stage we studied the state of continuity of an elastic-brittle solid, and at the second stage, the state of pre-fracture, when normal fracture cracks of critical size were generated (nucleated); the third stage was characterized by the state of crack growth as through cracks separating a piece of rock into separate parts. The force approach adopted in the calculation scheme predetermines the development of studies on the stress and strain state of the borehole surface also according to the three-stage scheme, when along with the state of continuity local deformations and stresses of the borehole surface are determined in connection with the opening of fracture cracks. The developed methodology of problem formulation and solution from the position of mechanical and physical theories of strength is a basic calculation model of rock fracture, which is fundamental for solving a number of practical problems of mining, as it includes the latest achievements of applied science on fracture of quasi-brittle materials.

Keywords

quasi-brittle body, intra-borehole pressure, cracking kinetics, ultimate fracture pressure, fracture energy intensity

For citation

Pershin G.D., Pshenichnaya E.G. Mechanism of Quasi-Static Fracture of Rock Volumes by a Spreading Action on the Borehole Walls. Vestnik Magnitogorskogo Gosudarstvennogo Tekhnicheskogo Universiteta im. G.I. Nosova [Vestnik of Nosov Magnitogorsk State Technical University]. 2024, vol. 22, no. 1, pp. 13-19. https://doi.org/10.18503/1995-2732-2024-22-1-13-19

Gennady D. Pershin – DrSc (Eng.), Professor, Professor of the Department of Mining Machines and Transport and Technological Complexes, Nosov Magnitogorsk State Technical University, Magnitogorsk, Russia.

Elena G. Pshenichnaya – PhD (Eng.), Senior Lecturer of the Department of Mechanics, Nosov Magnitogorsk State Technical University, Magnitogorsk, Russia. Email: This email address is being protected from spambots. You need JavaScript enabled to view it..

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