НЕФТЯНАЯ ПРОВИНЦИЯ

Abstract

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Effect of dimensions of rock samples characterized by anisotropy-associated variations in strength vs. direction is discussed. Subjects of such studies are isotropic rocks, as a rule, however, when anisotropy of strength properties is high, findings of research can be of interest. For this study, input data from published literature were used. Some authors mention that aspect ratio changed over a wide range. Failure criterion, which is essentially a generalization of a classical Mohr–Coulomb linear criterion, was used to determine shear strength and angles of internal friction along various directions. No physical experiments were performed. The problem was solved for conditions of lateral thrust variations; failure pressure for different lateral thrust – failure pressure ratios was determined. Calculations show that the effect of dimensions of rock samples is mostly pronounced when failure pressure is notable across or along the layers at different lateral thrust. In the range of 30° to 60°, the effect is minimal.

Key words:

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anisotropy, sample size, strength, load, layers, compression, rock, strength criterion

References

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Authors

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M.M. Aliev, Doctor, Professor, Almetyevsk State Oil Institute

2, Lenin st., Almetyevsk, 423450, Russian Federation

Е-mail: aliev@agni-rt.ru

 

Z.F. Ismagilova, Candidate of Technical Sciences, Assistant Professor, Almetyevsk State Oil Institute

2, Lenin st., Almetyevsk, 423450, Russian Federation

Е-mail: iiii.iskandar@inbox.ru

 

N.N. Burmistrova, Senior Lecturer,

2, Lenin st., Almetyevsk, 423450, Russian Federation

Е-mail: nataliyavika@yandex.ru

 

E.A. Sozontova, Postgraduate student of the Department «Oil and Gas Transportation and Storage», Almetyevsk State Oil Institute

2, Lenin st., Almetyevsk, 423450, Russian Federation

Е-mail: sozontova2608@mail.ru

For citation:

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M.M. Aliev, Z.F. Ismagilova, N.N. Burmistrova, E.A. Sozontova Vlijanie razmerov obrazca gornoj porody na anizotropiju prochnostnyh svojstv [Influence of rock sample size on anisotropy of strength properties]. Neftyanaya Provintsiya, No. 2(30), 2022. pp. 88-97. DOI https://doi.org/10.25689/NP.2022.2.88-97. EDN LGRAVP (in Russian)