THERMAL SCIENCE

International Scientific Journal

DIRECT TENSILE MECHANICAL PROPERTIES AND ACOUSTICE MISSION CHARACTERISTICS OF COAL AT DIFFERENT DEPTHS OF PINGDINGSHAN MINING AREA

ABSTRACT
Uncertainties in the basic theory of shallow mining that continues to be used in deep mining result in frequent engineering disasters with deep characteristics. Thus, it is necessary to elucidate the mechanism of mechanical deformation and failure behavior of coal from shallow to deep depths. Coal samples from the same coal seam in the Pingdingshan mining area of Henan Province were obtained at depths of 300 m, 600 m, 700 m, 850 m, and 1050 m. Direct tensile tests were conducted on the coal samples obtained at different depths. The tensile strength exhibits as low decreasing trend with increasing depth, reaching a minimum at 1050 m. This variation trend is consistent with that of acoustic emission cumulative ring-down counts and the cumulative energy measured during tensile tests on coal samples obtained at different depths. These conclusions provide a reference for the differences between the mechanical behavior of shallow and deep coal, which has both theoretical and engineering significance.
KEYWORDS
PAPER SUBMITTED: 2021-04-13
PAPER REVISED: 2021-06-15
PAPER ACCEPTED: 2021-07-22
PUBLISHED ONLINE: 2021-12-24
DOI REFERENCE: https://doi.org/10.2298/TSCI2106495Z
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2021, VOLUME 25, ISSUE Issue 6, PAGES [4495 - 4503]
REFERENCES
  1. Zhou, H, W., et al., Developments in Researches on Mechanical Behaviors of Rock under the Condition of High Ground Pressure in the Depths (in Chinese), Advances in Mechanics, 35 (2005), 2, pp. 91-99
  2. Xie, H, P., et al., Study on the Mechanical Properties and Mechanical Response of Coal Mining at 1000 m or Deeper, Rock Mechanics and Rock Engineering, 52 (2018), 6, pp. 1475-1490
  3. Xie, H, P., et al., Quantitative Definition and Investigation of Deep Mining (in Chinese), Journal of China Coal Society, 40 (2015), 1, pp. 1-10
  4. Man, K., et al., Research on Dynamic Tension Property of Granite at Different Depth in TIANHU Area of Xinjiang Autonomous Region (in Chinese), Engineering Mechanics, 35 (2018), 3, pp. 200-209
  5. Liu, Q. Y., et al., Physical Properties of Coal from Different Depths (in Chinese), Journal of China Coal Society, 42 (2017), 8, pp. 2101-2109
  6. Zhou, H, W., et al., Experimental Study of the Effect of Depth on Mechanical Parameters of Rock (in Chinese), Chinese Sci Bull (Chinese Ver), 55 (2010), 9, pp. 3276-3284
  7. Zuo, J, P., et al., Study on the Effect of Buried Depth on Failure and Energy Characteristics of the Basalt (in Chinese), Chinese Journal of Underground Space and Engineerin, 7 (2011), 12, pp. 1174-1180
  8. Zhang, Z, T., et al. Deformation Damage and Energy Evolution Characteristics of Coal at Different Depths, Rock Mechanics and Rock Engineering, 52 (2018), 2, pp. 1-13
  9. Li, S. L., et al., Studies on Acoustic Emission Characteristics of Uniaxial Compressive Rock Failure (in Chinese), Chinese Journal of Rock Mechanics and Engineering, 23 (2004), 8, pp. 2499-2503
  10. Meredith, P. G., et al., Microcrack Formation and Material Softening in Rock Measured by Monitoring Acoustic Emissions, International Journal of Rock Mechanics & Mining Sciences & Geomechanics Abstracts, 30 (1993), 1, pp. 11-24
  11. Lockner, D. A., The Role of Acoustic Emission in the Study of Rock Fracture, International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 30 (1993), 4, pp. 883-899
  12. Zhang, Z. P., et al., Differences in the Acoustic Emission Characteristics of Rock Salt Compared with Granite and Marble during the Damage Evolution Process, Environmental Earth Sciences, 73 (2015), 4, pp. 6987-6999
  13. Zhang, Z, T., et al., Mechanical Properties and Acoustic Emission Characteristics of Coal under Direct Tensile Loading Conditions (in Chinese), Journal of China Coal Society, 38 (2013), 12, pp. 960-965
  14. Jia, Z. Q., et al., Influence of Water-Soaking Time on the Acoustic Emission Characteristics and Spatial Fractal Dimensions of Coal under Uniaxial Compression, Thermal Science, 21 (2017), 5, pp. 327-334
  15. Yang, Y, M., et al., Acoustic Emission Characteristics of Coal Samples under Different Stress Paths Corresponding to Different Mining Lay-outs, Energies, 13 (2020), 6, pp. 1-13
  16. Kachanov, M., On the Time to Failure under Creep Condition, Izv AN SSSR Otd Tekhn Nauk, 8 (1958), 2, pp. 26-31
  17. Lemaitre, J., Evaluation of Dissipation and Damage in Metals Submitted to Dynamic Loading, Proceedings, ICM-1, Kyoto, Japan, 1972

© 2022 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence