Generalized analytical criterion of plasticity, strength and fracture of rocks for the conditions volume unequicomponent compression

The work is devoted to the derivation of a generalized unified analytical criterion of plasticity (elastic limit), strength and fracture of rocks for the case of volumetric nonequivalent compression. The proposed analytical criterion has neither empirical nor analytical analogues. A distinctive feature of the proposed criterion is that for the first time in world practice, one analytical dependence describes the full branch of plastic deformation in the principal stress components, from the elastic limit to the limit of residual strength. On the basis of the advanced criterion, a strength criterion was obtained for a two-phase medium under triaxial compression, that is, for rocks in the presence of a pore pressure of a liquid (water). The paper discusses in detail and proposes a new view on the mechanism of plastic deformation of rock at the hardening stage. The translational-rotational nature of plastic deformation in the vicinity of shear areas is indicated, which results in an increase in the strength of rocks (hardening) and the phenomenon of dilatancy. Thus, a fundamentally new character of the accumulation of the potential energy of deformation at the hardening stage, in contrast to the elastic phase, is indicated, which is the reason for the impact hazard of the rock. A criterion for quasi-plastic deformation of a rock is given, that is, a criterion for the absence of hardening, dilatancy and acoustic emission, and a conclusion is made about its good agreement with the data of experimental studies.

Zhabkо A. V. Generalized analytical criterion of plasticity, strength and fracture of rocks for the conditions volume unequicomponent compression. MIAB. Mining Inf. Anal. Bull. 2024;(1-1):5—20. [In Russ]. DOI: 10.25018/0236_1493_2024_011_0_5.

Zhabkо A. V., Dr. Sci. (Eng.), Associate Professor, Head of the Department, Ural State Mining University, Yekaterinburg, 620144, Russia, zhabkoav@mail.ru.

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