HARDWARE AND METHODOLOGICAL SUPPORT OF COMPLEX STRESS-STRAIN STATE MONITORING OF ROCK MASSIF USING MEMORY EFFECTS IN ELASTIC COMPOSITIVE SENSORS

Promising methods for estimating the stress state of the rock massif, based on manifestations of the Kaiser effect in various rocks, are considered. It is noted that a further increase in the accuracy and reliability of control is possible only by replacing of «memory carrier» is from rocks to composite materials synthesized under laboratory conditions. The results of earlier studies of the formation and manifestation of the Kaiser effect in a number of composite materials under complex stress state conditions are presented. The potential possibility of using the identified patterns for rock pressure control is noted while a number of issues of instrumental and methodological support should be solved. The paper proposes the design of a portable electronic unit for recording the Kaiser effect. It provides signaling that an acoustic emission exceeds a predeter-mined threshold level. It is also proposed to use computer modeling for solving a number of methodological issues of using method in-situ. The solution of the finite element problem allowed to establish that when a composite cylinder with a ratio of length and diameter equal to 4 is placed at the end of the measuring well, it can accept massif stresses directed along the well axis. Also on the basis of computer modeling for the development system used at SKRU-3 of OJSC «Uralkali», typical values of stress deviators near workings were established. The critical values of deviators are also established, at which the destruction of the basic elements of development systems may occur. Based on the results of experimental studies and computer modeling, a method for monitoring a complex stress state is formulated, which allows to measure changes in stress deviators in the monitoring mode.

This work was done with the financial support of the Russian Science Foundation (project No. 17-77-10009).

Keywords

Kaiser Effect, stress-strain state, rock mass, control, computer simulation, composite material.

Issue number: 2
Year: 2019
ISBN: 622.02:539.2
UDK:
DOI: 10.25018/0236-1493-2019-02-0-97-104
Authors: Nikolenko P. V.

About authors: Nikolenko P.V., Candidate of Technical Sciences, Assistant Professor, e-mail: petrov-87@mail.ru, National University of Science and Technology «MISiS», 119049, Moscow, Russia.

REFERENCES:

1. Han J. Zhang H. Liang B., Rong H., Lan T., Liu Y., Ren T. Influence of Large Syncline on In Situ Stress Field: A Case Study of the Kaiping Coalfield, Chinа, Rock Mechanics and Rock Engineering, 2016, Vol. 49, Issue 11, pp. 4423—4440.

2. Li Q., He J.-J., Li C.-X. Relationship between the ultrasonic velocities and strata pressure of the coalbed methane reservoir in qinshui basin by rock physical testing, Wutan Huatan Jisuan Jishu. 2013, Vol. 35, Iss. 4, pp. 382—386.

3. Jiang H., Zhang J., Jiang R. Stress evaluation for rocks and structural concrete members through ultrasonic wave analysis: Review. Journal of Materials in Civil Engineering. 2017, Vol. 29, Issue 10, Article number 04017172.

4. Shkuratnik V.L., Nikolenko P.V., Kormnov A.A. Ultrasonic correlation logging for roof rock structure diagnostics, Journal of Mining Science, 2015, Vol. 51, Issue 3, pp. 456—461.

5. Feng Z., Mingjie X., Zhonggao M., Liang C., Zhu Z., Juan L. An experimental study on the correlation between the elastic wave velocity and microfractures in coal rock from the Qingshui basin. Journal of Geophysics and Engineering, 2012, Vol. 9, Iss. 6, pp. 691—696.

6. Lavrov A. The Kaiser effect in rocks: principles and stress estimation techniques. International Journal of Rock Mechanics and Mining Sciences. 2003, Vol. 40, No 2. pp. 151—171.

7. Wang H.-J., Tang L., Ren X.-H., Yang A.-Y., Niu. Y. Mechanism of rock deformation memory effect in low stress region and its memory fading. Rock and Soil Mechanics. 2014, Vol. 35, Issue. 4, pp. 1007—1014.

8. Hardy H. R. jr., Zhang D., Zelanko J. C. Recent studies of the Kaiser effect in geological materials. In: Proceedings of the Fourth Conference, AE/MA in Geologic Structures and Materials, Clausthal-Zellerfeld: Trans Tech Publications, 1989.

9. Amann F., Gonidec Y. L., Senis M., Gschwind S., Wassermann J., Nussbaum C., Sarout J. Analysis of acoustic emissions recorded during a mine-by experiment in an underground research laboratory in clay shales. International Journal of Rock Mechanics and Mining Sciences. 2018, Vol. 106, pp. 51—59.

10. Nikolenko P. V., Nabatov V. V. Interference protection in geoacoustic control of critical stresses in rocks. Gornyi Zhurnal. 2015, Vol. 2015, Issue 9, pp. 33—36.

11. Kaiser J. Erkenntnisse und Folgerungen aus der Messung von Gerauschen bei Zug-beanspruchimg von metallischen Werkstoffen. Archiv fur das Eisenhuttenwesen. 1953. Vol. 24. No 1/2, pp. 43—45.

12. Li C. A theory for Kaiser effect and its potential applications. Proc. 6th Conf. AE/MA in Geologic Structures and Materials. Clausthal-Zellerfeld, Trans Tech Publications, 1998, pp. 171—185.

13. Holcomb D. J. Costin L. S. Detecting damage surfaces in brittle materials using acoustic emission.Journ. Appl. Mech. Trans. ASME, 1986. Vol. 53. No. 3, pp. 536—544.

14. Nikolenko P. V., Shkuratnik V. L., Chepur M. D., Koshelev A. E.. Using the Kaiser Effect in Composites for Stressed Rock Mass Control, Journal of Mining Science, 2018, Vol. 55, Issue 1, pp. 21—26.

15. Baryakh A. A. Asanov V. A. Pan'kov I. L. Fiziko-mekhanicheskie svoystva solyanykh porod Verkhnekamskogo kaliynogo mestorozhdeniya: uchebnoe posobie [Physical and mechanical properties of salt rocks of Verkhnekamskoye potash deposit: Educational aid], Perm', Izd-vo Perm. gos. tekhn. un-ta, 2008, 199 p.

16. Asanov V. A., Toksarov V. N., Evseev A. V., Bel'tyukov N. L. Naturnye issledovaniya napryazhennogo sostoyaniya porod prikonturnogo massiva [Field studies of the stress state of the rocks of the marginal massif], Vestnik Permskogo natsional'nogo issledovatel'skogo politekhnicheskogo universiteta. Geologiya. Neftegazovoe i gornoe delo. 2016, Vol. 15, No 20, pp. 270—276. [In Russ].

Subscribe for our dispatch