The elastic hysteresis of rocks of different nature

The paper is devoted to the study of elastic hysteresis of rock samples in lab. Evaluation of elastic hysteresis’s parameters characterizing elastic hysteresis is carried out in a given range of stresses in the samples caused by mechanical stress. The paper briefly substantiates the selection of rock and the production of samples, and also briefly describes the method of mechanical static testing, which forms the behavior of the samples at specified stresses and fix deformations as a result of loading and unloading. The results of tests on the deformation of rock samples under conditions of elastic hysteresis are obtained, and the arising nonlinear effects are discussed. The nonlinear behavior of the deformation of the samples has been substantiated on the basis of the physical simulated mechanisms of the evolution of the microstructure of the samples. Micromechanical approaches and results are discussed that allow explaining residual deformations at the initial stage of cyclic loads and stabilization of the geomaterial structure in subsequent stages and for assessing its nonlinear elastic properties. As a result of processing the experimental data, mathematical models have been proposed for various rocks, which make it possible to determine the nonlinear parameters of elastic hysteresis: static elastic moduli and hysteresis parameter. A micromechanical model is presented as a rationale that allows one to assess the degree of nonlinearity of elastic-plastic deformation.

Vysotin N. G. The elastic hysteresis of rocks of different nature. MIAB. Mining Inf. Anal. Bull. 2022;(5—2):72—79. [In Russ]. DOI: 10.25018/0236_1493_2022_52_0_72.

Vysotin N. G., senior lecturer, http://orcid.org/ 0000-0002-3011-053X, NUST “MISIS”, 119991, Moscow, Leninskiy prospect, 4, Russia, e-mail: n.vysotin@misis.ru.

Vysotin N. G., e-mail: n.vysotin@misis.ru.

1. Ostrovsky L. A., Johnson P. A. Dynamic nonlinear elasticity in geomaterials. La Rivista del Nuovo Cimento della Societa Italiana di Fisica. 2001, vol. 24, no. 7, pp. 1—46.

2. Nazarov V. E., Radostin A. V., Ostrovsky L. A., Soustova I. A. Wave processes in media with hysteretic nonlinearity. Part I. Acoustical Physics. 2003, no. 49 (4), pp. 344— 353. DOI: 10.1134/1.1591300.

3. Aleshin V. V., Van Den Abeele K. Preisach description for solids with frictional cracks. International Journal of Non-Linear Mechanics. 2018, vol. 104, pp. 28—38. DOI: 10.1016/j.ijnonlinmec.2017.12.010.

4. Yang D., Zhang D., Niu S., Feng W., Ge S. Experiment and Study on Mechanical Property of Sandstone Post-peak Under the Cyclic Loading and Unloading. Geotechnical and Geological Engineering. 2018, vol. 36, iss. 3, pp. 1609—1620. DOI: 10.1007/s10706— 017—0414—6.

5. Han D., Li K., Meng J. Evolution of nonlinear elasticity and crack damage of rock joint under cyclic tension. International Journal of Rock Mechanics and Mining Sciences. 2020, no. 128, pр. 1—9. DOI: 10.1016/j.ijrmms.2020.104286.

6. Song H., Zhang H., Fu D., Zhang Q. Experimental analysis and characterization of damage evolution in rock under cyclic loading. International Journal of Rock Mechanics & Mining Sciences. 2016, no. 88, pp. 157—164. DOI:10.1016/j.ijrmms.2016.07.015.

7. Vinnikov V. A., Zakharov V. N., Malinnikova O. N., Cherepetskaya E. B. Analysis of structure and elastic properties of geomaterials using contact broadband ultrasonic structural spectroscopy. Gornyj zhurnal. 2017, no. 4, pp. 29—33. DOI: 10.17580/gzh.2017.04.05. [In Russ]

8. Blokhin D. I., Kharchenko A. V. Complex study of acoustoemission and thermomechanical effects in samples of rock salt at their cyclic deformation. MIAB. Mining Inf. Anal. Bull. 2021, no. 4—1, pp. 129—137. DOI: 10.25018/0236_1493_2021_41_0_129. [In Russ].

9. Wang Y., Zhao L., Han D.-h., Qin X., Ren J., Wei Q. Micro-mechanical analisys of the effects of stress cycles on the dynamic and static mechanical properties of sandstone. International Journal of Rock Mechanics and Mining Sciences. 2020, vol. 134, no. 104431. DOI: 10.1016/j.ijrmms.2020.104431.

10. Vysotin N. G. The specific non-linear elastic hysteresis of rocks under cyclic uniaxial Tension, MIAB. Mining Inf. Anal. Bull. 2021, no.4—1, pp. 148—157. DOI: 10.25018/0236_1493_2021_41_0_148. [In Russ].

11. Stefanov Ju. P. Nonlinear effects of rock behavior and interpretation of experimental data. The 4-th tectonophysical conference at IPE RAS. Tectonophysics and topical issues of earth sciences. Collection of Scientific Papers. Moscow. 2016, pp. 358—371. [In Russ].

12. Bogusz A., Bukowska M. Strees-strain characteristics as a source of information on the disraction of rocks under influence of load. Journal of Sustainable Mining. 2015, no. 14, pp. 46—54. DOI: 10.1016/j.jsm.2015.08.007.

13. Vinnikov V. A., Vysotin N. G. Method of testing on the static module for the elasticity of mineral rocks with using the results of laser-ultrasonic spectroscopy. MIAB. Mining Inf. Anal. Bull. 2018, no. S1, pp.90—101. DOI: 10.25018/0236—1493—2018—1-1—90—101. [In Russ].

14. DIN 14580—2005. Prüfverfahren für Naturstein Bestimmung des statischen Elastizitätsmoduls, Berlin, Deutsches Institut für Normung e.V. 2005.

15. Suknjov S. V., Fjodorov S. P. Methods for determining the elastic properties of rocks. The Science and the Education. 2014, no. 1(73), pp. 18—24. [In Russ].