Prediction of the integrity of the water-protective stratum at the Verkhnekamskoye potash ore deposit

The paper presents a study of the stress-strain state of rocks composing the waterprotective strata during the development of the first western block of the second northwest panel (2 — NWP) at the Bereznikovsky Potash Production Department No. 4 (BKPRU-4) mine, Verkhnekamskoe potassium-magnesium salt deposit. Mineral development is carried out at a depth of 380 m. The numerical implementation of the model is carried out by the finite element method in the Simulia Abaqus software package using a viscoelastic-plastic geomechanical model of sylvinite rock. The parametric support of the rheological model is carried out on the basis of laboratory studies of rock samples. The forecast was carried out for a period of 150 years after the panel was fully developed. The mathematical model is made in the formulation of plane deformation. The integrity of the WPS sections was checked on the basis of Protodyakonov strength criterion. It has been established that without the use of measures to ensure the integrity of the WPS, a hydraulically connected system of water-conducting cracks is formed, which can lead to flooding of the mine and the formation of karst sinkholes. This system is close to goaf and has a width of 8 meters along the length of the block, and has a minimum length equal to the width of the block — 50 m. Based on the results of the study, it is necessary to apply measures to ensure the integrity of the WPS, taking into account the rheological nature of deformation of the interchamber pillars.

Belyakov N. A., Belikov A. A. Prediction of the integrity of the water-protective stratum at the Verkhnekamskoye potash ore deposit. MIAB. Mining Inf. Anal. Bull. 2022;(6−2):33—46. [In Russ]. DOI: 10.25018/0236_1493_2022_62_0_33.

The study was carried out at the expense of a subsidy for the fulfillment of the state task in the field of scientific activity for 2021 No. FSRW-2020−0014.

Belyakov N. A.¹, Cand. Sci. (Eng.), Associate Professor of the Department of Construction of Mining Enterprises and Underground Structures, http://orcid.org/0000-0002-9754-501X, e-mail: Belyakov_NA@pers.spmi.ru;
Belikov A.A.¹, postgraduate student of the department of construction of mining enterprises and underground structures, https://orcid.org/0000-0001-5051-0680, e-mail: s205046@stud.spmi.ru;
¹ Saint Petersburg Mining University, 199106, St. Petersburg, Vasilievsky Island, 21 line 2, Russia. 

Artem A. Belikov, e-mail: s205046@stud.spmi.ru.

1. Aparin A. G., Sankovsky A. A. Peculiarities of passing through a temperature gradient in vertical shaft sinking with artificial ground freezing. MIAB. Mining Inf. Anal. Bull. 2022, no. 2, pp. 51–61 DOI: 10.25018/0236_1493_2022_2_0_51 [In Russ].

2. Warren J. K. Evaporites. A Geological Compendium. 2nd edition. Springer, 2016, 1812 p. DOI: 10.1007/978−3-319−13512−0.

3. Baryakh A. A. Assessment of the risks of disruption of the continuity of the water protection strata: approaches and realitiesю. Strategy and processes for the development of georesources: collection of articles. scientific. tr. Issue 12. State Institute of the Ural Branch of the Russian Academy of Sciences. Perm. 2014, pp. 68–71. [In Russ].

4. Baryakh A. A., Sanfirov I. A., Fedoseev A. K. Seismic–Geomechanical Control of Water-Impervious Strata in Potassium Mines. Journal of Mining Science. 2017, vol. 53(6), pp. 981–992. DOI: 10.1134/S1062739117063041.

5. Kashnikov Yu. A., Ermashov A. O., Efimov A. A. Geological and geomechanical model of the section of the Verkhnekamskoye potash deposit. Journal of Mining Institute. 2019, no. 237, pp. 259–267. [In Russ]. DOI: 10.31897 / PMI.2019.3.259

6. Kashnikov Yu, Shustov D, Ermashov A, Lebedeva O., Zhukov A., Prigara A. Solving the problems of exploitation safety of potassium salt deposit based on joint application of geophysical and geomechanical studies. IOP Conference Series: Earth and Environmental Science. 2021, vol. 833, pp. 1–8. DOI: 10.1088/1755−1315/833/1/012084.

7. Kulikova A. A., Ovchinnikova T. I. On the issue of reducing geoecological risks at mining enterprises. MIAB. Mining Inf. Anal. Bull. 2021, no. 2—1, pp. 251–262. [In Russ]. DOI: 10.25018/0236−1493-2021−21−0-251−262.

8. Baryakh A. A., Gubanova E. A. On measures to protect potash mines from flooding. Journal of Mining Institute. 2019, no. 240, pp. 613–620 DOI: 10.31897 / PMI.2019.6.613 [In Russ].

9. Baryakh A. A., Stazhevskii S. B., Timofeev E. A. Strain state of a rock mass above karst cavities. Journal of Mining Science. 2008, vol. 44(6), pp. 531–538. DOI: 10.1007/ s10913-008-0059-1.

10. Zubov V. P., Sokol D. G. Temperature effect on implementation of mining system improvement for the potash-bearing strata in Starobin deposit. Gornyi Zhurnal. 2020, no. 10, pp. 74–79. [In Russ]. DOI: 10.17580/gzh.2020.10.07.

11. Sankovsky A. A., Kovalsky E. R. Estimation of the parameters of the stress-strain state of the massif in the vicinity of the treatment chambers. Journal of Mining Institute. 2014, no. 207, pp. 63–65. [In Russ].

12. Gusev V. N., Ilyukhin D. A., Aleksenko A. G. Determination of the parameters of the zone of water-conducting cracks through horizontal deformations of the undermined thickness. Journal of Mining Institute. 2013, no 204, pp. 69–73. [In Russ].

13. Gusev V. N. Prediction of safe conditions for the development of a suite of coal seams under water bodies based on the geomechanics of technogenic water-conducting cracks. Journal of Mining Institute. 2016, no. 221, pp. 638–643. [In Russ]. DOI: 10.18454/ pmi.2016.5.638.

14. Gusev V. N., Maliukhina E. M., Volokhov E. M. Assessment of development of water conducting fractures zone in the massif over crown of arch of tunneling (construction). International Journal of Civil Engineering and Technology. 2019, no. 2, pp. 635–643.

15. Kudryashov A. I. Verkhnekamskoe deposit of salts. 2nd edition. Moscow, “Epsilon Plus”, 2013, 378 p. [In Russ].

16. Dzhinoridze N. M. Petrotectonic foundations of safe operation of the Verkhnekamskoe deposit of potassium-magnesium salts, OGUP, St. Petersburg — Solikamsk, 2000, 400 p. [In Russ].

17. Baryakh A. A., Lobanov S. Y., Lomakin I. S. Analysis of time-to-time variation of load on interchamber pillars in mines of the Upper Kama Potash Salt Deposit. Journal of Mining Science. 2015, vol. 51(4), pp. 696–706. DOI: 10.1134/S1062739115040064.

18. Vermeer P. A. de Borst R. Non-Associated Plasticity for Soils: Concrete and Rock. Heron. 1984, no. 29 (3), рp. 3–64. DOI: 10.1007 / 978-94-017-2653−5_10.

19. Rauche H. Die Kaliindustrie im 21, Jahrhundert, [The Potash Industry in the 21st Century]. Springer, Vieweg, 2016, 580 p.

20. Shiman M. I. Prevention of flooding of potash mines. Moscow, Nedra, 1992, 176 p. [In Russ].

21. Karasev M. A., Protosenya A. G., Katerov A. M., Petrushin V. V. Analysis of shaft lining stress state in anhydrite-rock salt transition zone // Rudarsko Geolosko Naftni Zbornik. 2022, no. 12, pp. 151−162. DOI: 10.17794/rgn.2022.1.13.

22. Gendler S. G., Fazylov I. R. Methods of regulation air temperature in the Russian oil mains. Topical issues of Rational Use of Natural Resources. London. Taylor & Francis Group. 2019. pp. 16–21. DOI: 10.1201/9781003014577−3.

23. Gendler S. G., Fazylov I. R. Application efficiency of closed gathering system toward microclimate normalization in operating galleries in oil mines. MIAB. Mining Inf. Anal. Bull. 2021. no. 9. pp. 65–78. [In Russ]. DOI: 10.25018/0236_1493_2021_9_0_65.

24. Karasev M. A., Sotnikov R. O., Sinegubov V. Y., Egorova N. A., Makarov K. V., Thorikov A. I. Development of a model for predicting the dynamic effect on the stability of rock excavation. Journal of Physics: Conference Series. 2019, vol 1384(1). рp. 1–7. DOI:1 0.1088/1742−6596/1384/1/012051.

25. Zhou H., Liu D., Lei G., Xue D., Zhao Y. The Creep-Damage Model of Salt Rock Based on Fractional Derivative. Energies. 2018, no. 11, pp. 1–9. DOI: 10.3390/en11092349.

26. Wu F., Chen J., Zou Q. A nonlinear creep damage model for salt rock. International. Journal of Damage Mechanics, 2018, no. 28(5), pp. 1–14. DOI:10.1177/1056789518792649.

27. Zuev B. Yu., Zubov V. P., Smychnik A. D. Determination of static and dynamic stresses in physical models of layered and block rock masses. Gornyi Zhurnal. 2019, no. 7, pp. 61–72. [In Russ]. DOI: 10.17580/gzh.2019.07.02.

28. Guo J. Liu X. Huang W. Mohr-Coulomb Strength Criterion Based on Elastic Strain Energy. Journal of Tongji University. 2018, vol. 46, pp. 1168–1174. DOI: 10.11908/j. issn.0253−374x.2018.09.002.

29. Ermashov A. O. Geomechanical substantiation of calculations of subsidence of the earth’s surface during the extraction of potassium-magnesium ores (on the example of the Verkhnekamskoye deposit of potassium-magnesium salts): Doctor’s thesis, Perm, Mining Institute, Ural Branch of the Russian Academy of Sciences, 2015, 20 p. [In Russ].

30. Zhang Y., Xiong X., Musa M., Lyu X. Analysis of a compressive strength model for FRP‐confined damaged concrete columns based on the Drucker–Prager yield criterion. Structural Concrete. 2022, vol. 24, pp.721–735. DOI: 10.1002/suco.202100584.

31. Taheri S. R., Pak A., Shad S., Mehrgini B., Razifar M. Investigation of rock salt layer creep and its effects on casing collapse. International Journal of Mining Science and Technology. 2020, no. 30, pp. 357–365. DOI: 10.1016/j.ijmst.2020.02.001.

32. Taheri S. R., Pak A. Casing Failure in Salt Rock: Numerical Investigation of its Causes. Rock Mechanics and Rock Engineering. 2020, no. 59, pp. 3903–3918. DOI: 10.1007/ s00603-020-02161-9.