Abstract
In order to study the failure mechanism and acoustic emission characteristics of coal–rock combination with different coal-to-rock ratios, carry out uniaxial compression test and acoustic emission test on coal–rock combination with three coal–rock ratios of 1:2, 1:1, 2:1, start with parameters such as failure characteristics, stress-time curve, compressive strength, elastic modulus, acoustic emission events and energy counts, and analyze the failure characteristics, deformation characteristics and acoustic emission characteristics of the combined body. The result shows the following. The destruction of the coal–rock assembly occurs in the coal body, with the increase of the coal-to-rock ratio, the damage degree of the specimen gradually decreases, the broken shape gradually changes from broken and collapsed, and after tensile splitting, it becomes oblique shear failure. There is a phenomenon of "stress jump" and residual stress in coal-rock combination, after the stress reaches the peak, it jumps to the maximum value of residual stress, the larger the coal–rock ratio, the smaller the peak stress, but the residual stress is almost unchanged. The compressive strength and elastic modulus of the composite body decrease with the increase of coal-rock ratio, and the maximum axial strain increases with the increase of coal–rock ratio. Acoustic emission events and energy counts both showed stage changes that matched the stress–time curve. The energy counts and event counts at the same stage decreased as the coal–rock ratio increased.
Similar content being viewed by others
REFERENCES
Dou, L. and He, X., Theory and Technology of Rockburst Prevention and Control, Xuzhou: China University Min. Technol. Press, 2001.
Qi, Q., Rockburst Theory and Technology, Xuzhou: China University Min. Technol. Press, 2008.
Du, T., Li, K., Lan, H. et al., Rockburst Process Analysis in Steeply-Inclined Extremely-Thick Coal Seam, J. Min. Safety Eng., 2018, vol. 35, no. 1, pp. 140–145.
Kang, H., Temporal Scale Analysis on Coal Mining and Strata Control Technologies, J. Min. Strata Control Eng., 2020, vol. 2, no. 2. — 023538.
Cook, N.G.W., The Failure of Rock, Int. J. Rock Mech. Min. Sci. Geomech. Abstracts, 1965, vol. 2, no. 4, pp. 389–403.
Bieniawski, Z.T., Denkhaus, H.G., and Vogler, U.W., Failure of Fractured Rock, Int. J. Rock Mech. Min. Sci. Geomech. Abstracts, 1969, vol. 6, no. 3, pp. 323–341.
Cook, N.G.W., Hoek, E., Pretorius, J.P.G., Ortlepp, W.D., and Salamon, M.D.G., Rock Mechanics Applied to the Study of Rock Bursts, J. South African Institute of Min. and Metal., 1965, vol. 66, no. 12, pp. 435–528.
Jin, L., Research on the Occurrence Conditions and Prediction Methods of Rock Bursts, Chongqing: Chongqing University, 1992.
Li, Y., Rockburst Mechanism and its Preliminary Application, J. China Institute Min. Technol., 1985, vol. 14, no. 3, pp. 37–43.
Zhang, M., Xu, Z., Pan, Y., A United Instability Theory on Coal (Rock) Burst and Outburst, J. China Coal Soc., 1991, vol. 16, no. 4, pp. 48–53.
Dou, L., Lu, C., and Mou, Z., Rock Burst Tendency of Coal–Rock Combinations Sample, J. Min. Safety Eng., 2006, vol. 23, no. 1, pp. 43–46.
Chen, Y., Zuo, J., Song, H. et al., Deformation and Crack Evolution of Coal–Rock Combined Body under Cyclic Loading-Unloading Effects, J. Min. Safety Eng., 2018, vol. 35, no. 4, pp. 826–833.
Zhao, Y.X., Jiang, Y.D., Zhu, J., and Sun, G.Z., Experimental Study on Precursory Information of Deformations of Coal–Rock Composite Samples before Failure, Chin. J. Rock Mech. Eng., 2008, vol. 27, no. 2, pp. 339–346.
Guo, D., Macro- and Mesoscopic Failure Test and Theoretical Study of Deep Coal–Rock Combinations in Huxi Mine, China University Min. Technol., Beijing, 2010.
Zuo, J. and Chen, Y., Investigation on Crack Recovery Effect of Coal–Rock Combined Body under the Influence of Unloading, J. China Coal Soc., 2017, vol. 42, no. 12, pp. 3142–3148.
Zuo, J., Song, H., Chen, Y., and Li, Y., Post-Peak Progressive Failure Characteristics and Nonlinear Model of Coal–Rock Combined Body, J. China Coal Soc., 2018, vol. 43, no. 12, pp. 3265–3272.
Zuo, J., Chen, Y., and Cui, F., Investigation on Mechanical Properties and Rock Burst Tendency of Different Coal–Rock Combined Bodies, J. China University Min. Technol., 2018, vol. 47, no. 1, pp. 81–87.
Miao, L., Niu, Y., and Shi, B., Impact Dynamic Tests for Rock–Coal–Rock Combination under Different Strain Rates, J. Vibration and Shock, 2019, vol. 38, no. 17, pp. 137–143.
Yu, Y., Zhu, W., Li, L. et al., Simulations on Hydraulic Fracture Propagation of Coal–Rock Combination in Deep Underground, J. Hazard Control Tunnel. Underground Eng., 2019, vol. 1, no. 3, pp. 96–108.
Liu, B., Huang, J., Wang, Z. et al., Study on Damage Evolution and Acoustic Emission Character of Coal Rock under Uniaxial Compression, Chinese J. Rock Mech. Eng., 2009, vol. 28, no. 1, pp. 3234–3238.
Xu, J., Li, S., Tang, X. et al., Rock Fatigue Damage Evolution Based on Acoustic Emission, J. University Sci. Technol. Beijing, 2009, vol. 31, no. 1, pp. 19–24.
Zhang, G., Deng, Z., Jiang, J. et al., Acoustic Emission Characteristics of Coal with Strong Impact Tendency under Different Loading Methods, J. Min. Safety Eng., 2020, vol. 37, no. 5, pp. 977–982.
Author information
Authors and Affiliations
Corresponding author
Additional information
Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, 2022, No. 3, pp. 50-58. https://doi.org/10.15372/FTPRPI20220305.
Rights and permissions
About this article
Cite this article
Guo, D., Zhang, W., Chen, Q. et al. Failure Mechanism and Acoustic Emission Characteristics of Coal–Rock Samples. J Min Sci 58, 390–397 (2022). https://doi.org/10.1134/S106273912203005X
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S106273912203005X