Advertisement

In Situ Investigation and Numerical Simulation of the Failure Depth of an Inclined Coal Seam Floor: A Case Study

  • Xiangxi Meng
  • Weitao LiuEmail author
  • Jiyuan ZhaoEmail author
  • Xiyang Ding
Technical Article
  • 15 Downloads

Abstract

The 1131 working face of the Yangcheng coal mine was used for a research demonstration to study the failure characteristics of an inclined coal seam floor. A numerical simulation was carried out using Flac3D software and a team-designed mining and failure observation system was used for an in situ investigation. The results included: (a) the failure characteristics along the inclined direction were consistent with that along the strike direction; the failure zone of the rock mass floor had an asymmetrical distribution, in that the lower plastic zone was large and the upper shaping zone was small; (b) The variation trend of the maximum principal stress was basically the same as the failure depth in the floor’s plastic zone. The failure depth reached a maximum when the working face advanced to 200 m. (c) The field-measured maximum floor failure depth was 31.5 m, while that of the numerical simulation was 32.3 m, indicating the results of the system measurements are accurate.

Keywords

Water inrush Failure characteristics Faults Water leakage 

In situ Untersuchung und numerische Simulation der Bruchtiefe des Liegenden eines geneigten Kohlenflözes

Zusammenfassung

Die Abbaufront 1131 der Yangcheng Kohlenmine wurde genutzt, um Forschung zur Untersuchung der Bruchcharakteristika des Liegenden eines geneigten Kohlenflözes zu demonstrieren. Eine numerische Simulation mittel Flac3D und ein von einem Team konzipiertes Beobachtungssystem wurden zur in situ Untersuchung eingesetzt. Die Ergebnisse umfassten: (a) die Bruchcharakteristika entlang der Neigungsrichtung waren konsistent mit jenen der Streichrichtung; die Bruchzone der liegenden Felsmasse zeigte eine unsymmetrische Verteilung, indem die liegende plastische Zone groß und die obere frei geformte Zone klein war. (b) Der Variationstrend der maximalen Hauptspannung war grundsätzlich gleich mit der Bruchtiefe in der plastischen Zone des Liegenden. Als die Abbaufront 200 m vorgetrieben war, erreichte die Bruchtiefe ein Maximum. (c) Eine Messung der maximalen Bruchtiefe in der Mine ergab 31.5 m, während die numerische Simulation in 32.3 m resultierte. Daraus wird geschlossen, daß die Ergebnisse der Systemmessungen korrekt sind.

Investigación in situ y simulación numérica de la profundidad de falla de una veta de carbón en piso inclinado: un estudio de caso

Resumen

La cara de trabajo 1131 de la mina de carbón Yangcheng se usó para una demostración para estudiar las características de falla de una veta de carbón en piso inclinado. Se realizó una simulación numérica utilizando el software Flac3D y se utilizó un sistema de observación de fallas y minería diseñado por el equipo para una investigación in situ. Los resultados incluyeron: (a) las características de falla a lo largo de la dirección inclinada fueron consistentes con las de la dirección de ataque; la zona de falla del piso de masa rocosa tenía una distribución asimétrica, en el sentido de que la zona plástica inferior era mayor y la zona de conformación superior era menor; (b) La tendencia de variación de la tensión principal máxima fue básicamente la misma que la profundidad de falla en la zona plástica del piso. La profundidad de falla alcanzó un máximo cuando la cara de trabajo avanzó a 200 m. (c) La profundidad máxima de falla del piso medida en el campo fue de 31,5 m, mientras que la simulación numérica fue de 32,3 m, lo que indica que los resultados de las mediciones del sistema son precisos.

倾斜煤层底板破坏深度的现场实测和数值模拟:案例研究

利用阳城煤矿1131工作面研究了倾斜煤层底板的破坏特征。利用Flac3D进行数值模拟,采用整套的采矿和破坏观测系统完成现场实测。研究结果包括:(a)沿倾向的破坏特征与沿走向一致;底板破坏区呈不对称分布,因为下部塑性区大而上部成形区小;(b)最大主应力的变化趋势与底板塑性区域破坏深度基本相同。当工作面推进至200 m时,破坏深度达到最大。(c) 现场实测底板最大破坏深度31.5 m,而数值模拟结果为32.3 m,表明现场的测量结果准确。

Notes

Acknowledgements

This work was financially supported by the National Natural Science Foundation of China (Grant 51274135 and 51774197), the State Key Research and Development Program of China (Grant 2017YFC0804108), and the SDUST Research Fund (Grant 2018TDJH102).

References

  1. Donnelly LJ (2006) A review of coal mining induced fault reactivation in Great Britain. A review of coal mining induced fault reactivation in Great Britain. Q J Eng Geol Hydrogeol 39(1):5–50CrossRefGoogle Scholar
  2. He GC, Xiao FG, Zhang ZJ, Ding DX (2011) Prediction of the height of the transmissive fractured belt of a mining stope under aquifer in Kangjiawan mine. J Min Safe Eng 28(01):122–126 (in Chinese) Google Scholar
  3. Hu XJ, Li WP, Cao DT, Liu MC (2012) Index of multiple factors and expected height of fully mechanized water flowing fractured zone. J Chin Coal Soc 37(4):613–618 (in Chinese) Google Scholar
  4. Huang WP, Gao YF, Wang B, Liu JR (2017) Evolution rule and development height of permeable fractured zone under combined-strata structure. J Min Safe Eng 34(2):330–335 (in Chinese) Google Scholar
  5. Li LC, Yang TH, Liang ZZ, Zhu WC, Tang CA (2011) Numerical investigation of groundwater outbursts near faults in underground coal mines. Int J Coal Geol 85(3):276–288Google Scholar
  6. Liu SC, Liu XM, Jiang H, Xing T, Chen M (2009) Research on electrical prediction for evaluating water conducting fracture zones in coal seam floor. Chin J Rock Mech Eng 28(02):348–356 (in Chinese) Google Scholar
  7. Liu WT, Mu DR, Xie XX, Yang L, Wang DH (2017a) Sensitivity analysis of the main factors controlling floor damage depth and a risk evaluation of floor water inrush for an inclined coal seam. Mine Water Environ 37(3):636–648CrossRefGoogle Scholar
  8. Liu WT, Mu DR, Yang L, Li LY, Xie XX (2017b) Calculation method and main factor sensitivity analysis of inclined coal floor damage depth. J Chin Coal Soc 42(4):849–859 (in Chinese) Google Scholar
  9. Liu WT, Song WC, Mu DR, Zhao JY (2017c) Section observation system on floor mining damage zone and its application. J Cent S Univ Sci Technol 48(10):2808–2816 (in Chinese) Google Scholar
  10. Meng XX, Liu WT, Mu DR (2018) Influence analysis of mining’s effect on failure characteristics of a coal Seam floor with faults: a numerical simulation case study in the Zhaolou coal mine. Mine Water Environ 37(4):754–762CrossRefGoogle Scholar
  11. Shi LQ, Xin HQ, Zhai PH, Li SC, Liu TB, Yan Y, Wei WX (2012) Calculating the height of water flowing fracture zone in deep mining. J Chin U Min Tech 41(1):37–41 (in Chinese) Google Scholar
  12. State Bureau of Coal Industry (2000) Regulations for coal mining and coal pillar design under buildings, water-bodies, railways and main shafts. China Coal Industry Publ House, BeijingGoogle Scholar
  13. Wang LG, Wang ZS, Huang JH, Zhou DL (2012) Prediction on the height of water-flowing fractured zone for shallow seam covered with thin bedrock and thick windblown sands. J Min Safe Eng 29(5):607–612 (in Chinese) Google Scholar
  14. Wu X, Wang XG, Duan QW, Yu QC, Yang J, Sun YD (2008) Numerical modeling about developing high of water flowing fractured zone. J China Coal Soc 33(6):609–612 (in Chinese) Google Scholar
  15. Wu Q, Zhu B, Liu SQ (2011) Flow-solid coupling simulation method analysis and time identification of lagging water-inrush near mine fault belt. Chin J Rock Mech Eng 30(1):93–104 (in Chinese) Google Scholar
  16. Wu Q, Liu Y, Luo L, Liu S, Sun W, Zeng Y (2015) Quantitative evaluation and prediction of water inrush vulnerability from aquifers overlying coal seams in Donghuantuo coal mine, China. Environ Earth Sci 74(2):1429–1437CrossRefGoogle Scholar
  17. Wu Q, Shen JJ, Liu WT, Wang Y (2017) A RBFNN-based method for the prediction of the developed height of a water-conductive fractured zone for fully mechanized mining with sublevel caving. Arab J Geosci 10(7):172CrossRefGoogle Scholar
  18. Xu M (2004) Study on the growth height of separation fracture of mining rock in Panxie area. J Chin Coal Soc 29(06):641–645 (in Chinese) Google Scholar
  19. Xu ZM, Sun YJ, Gong SY (2012) Monitoring and numerical and numerical and numerical simulation of formation of water inrush pathway caused by coal mining above confined water with high pressure. Chin J Rock Mech Eng 31(8):1698–1704 (in Chinese) Google Scholar
  20. Xu P, Zhou YJ, Zhang MX, Li JW, Cao ZZ (2015) Fracture development of overlying strata by backfill mining under thick alluvium and thin bedrock. J Min Safe Eng 32(04):617–622 (in Chinese) Google Scholar
  21. Zhang JC, Zhang YZ, Liu TQ (1997) Rock mass seepage and coal floor water inrush. Geological Publ House, Beijing, pp 19–32Google Scholar
  22. Zhang HQ, He YN, Tang CA, Ahmad B, Han LJ (2009) Application of an improved flow-stress-damage model to the critically assessment of water inrush in a mine: a case study. Rock Mech Rock Eng 41(6):911–930CrossRefGoogle Scholar
  23. Zhang PS, Hu XW, Liu SD (2011) Study of dynamic detection simulation of overburden failure in model workface. Chin J Rock Mech Eng 30(1):78–83 (in Chinese) CrossRefGoogle Scholar
  24. Zhang W, Zhang D, Qi D, Hu W, He Z, Zhang W (2017) Floor failure depth of upper coal seam during close coal seams mining and its novel detection method. Energ Explor Exploit 36(5):1265–1278CrossRefGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.College of Mining and Safety EngineeringShandong University of Science and TechnologyQingdaoChina
  2. 2.Yangcheng Coal Mine of Jining Mining GroupJiningChina

Personalised recommendations