Internal mechanism of asymmetric deformation and failure characteristics of the roof for longwall mining of a steeply dipping coal seam

• Autorzy: Luo Shenghu , Wang Tong , Wu Yongping , Huangfu Jingyu , Zhao Huatao

Identyfikatory

DOI

10.24425/ams.2021.136695

• Języki publikacji: EN

Abstrakty

EN

Stability control of the roof is the key to safe and efficient mining of the longwall working face for a steeply dipping coal seam. In this study, a comprehensive analysis was performed on the roof destruction, migration, and filling characteristics of a steeply dipping longwall working face in an actual coalmine. Elastic foundation theory was used to construct a roof mechanics model; the effect of the coal seam inclination angle on the asymmetric deformation and failure of the roof under the constraint of an unbalanced gangue filling was considered. According to the model, increasing the coal seam angle, thickness of the immediate roof, and length of the working face as well as decreasing the thickness of the coal seam can increase the length of the contact area formed by the caving gangue in the lower area of the slope. Changes to the length of the contact area affect the forces and boundary conditions of the main roof. Increasing the coal seam angle reduces the deformation of the main roof, and the position of peak deflection migrates from the middle of the working face to the upper middle. Meanwhile, the position of the peak rotation angle migrates from the lower area of the working face to the upper area. The peak bending moment decreases continuously, and its position migrates from the headgate T-junction to the tailgate T-junction and then the middle of the working face. Field test results verified the rationality of the mechanics model. These findings reveal the effect of the inclination coal seam angle on roof deformation and failure and provide theoretical guidance for engineering practice.

Słowa kluczowe

EN

steeply dipping seam; gangue; slip filling; deformation failure; main roof; angle effect

PL

odkształcenie; pokłady węgla; szyb kopalniany

• Wydawca: Instytut Mechaniki Górotworu PAN
• Czasopismo: Archives of Mining Sciences
• Rocznik: 2021
• Tom: Vol. 66, no. 1
• Strony: 101--124
• Opis fizyczny: Bibliogr. 26 poz., fot., rys., tab., wykr.

Twórcy

autor

Luo Shenghu

• Xi’An University of Science and Technology, Department of Mechanics, China

• https://orcid.org/0000-0002-3120-3340

autor

Wang Tong

• Xi’An University of Science and Technology, School of Energy Engineering, China

• https://orcid.org/0000-0001-8413-6826

autor

Wu Yongping

• Xi’An University of Science and Technology, School of Energy Engineering, China

• https://orcid.org/0000-0003-1617-2651

autor

Huangfu Jingyu

• Xi’An University of Science and Technology, School of Energy Engineering, China

• https://orcid.org/0000-0002-4285-9935

autor

Zhao Huatao

• Shandong Mining Machinery Group Co., Ltd. China

• https://orcid.org/000-0003-0713-6616

Bibliografia

• [1] Y.P. Wu, D.F Yun, P.S. Xie et al., Progress, practice and scientific issues in steeply dipping coal seams fullymechanized mining. J. China Coal Soc. 45 (01):24-34 (2020) (in Chinese).
• [2] Y.P. Wu, B.S. Hu, D Lang et al., Risk assessment approach for rockfall hazards in steeply dipping coal seams. Int. J. Rock Mech. Min. Sci. 138, 104626 (2021). doi: 10.1016/j.ijrmms.2021.104626.
• [3] D .Y. Zhu, W.L. Gong, Y. Su et al., Application of High-Strength Lightweight Concrete in Gob-Side Entry Retaining in Inclined Coal Seam. Advances in Materials Science and Engineering (2020). doi: 10.1155/2020/8167038.
• [4] H .W. Wang, Y.P. Wu, J.Q. Jiao et al., Stability Mechanism and Control Technology for Fully Mechanized Caving Mining of Steeply Inclined Extra-Thick Seams with Variable Angles. Mining, Metall. Explor. (2020). doi: 10.1007/ s42461-020-00360-0.
• [5] R .A. Frumkin, Predicting rock behaviour in steep seam faces (in Russian). International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts 20 (1), A12-A13 (1983). doi: 10.1016/0148-9062(83)91717-5.
• [6] A. Ladenko, Improvements in working steep seams. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts 11 (12), 247. (1974). doi: 10.1016/0148-9062(74)92108-1.
• [7] Z. Rak, J. Stasica, Z. Burtan et al., Technical aspects of mining rate improvement in steeply inclined coal seams: A case study. Resources 9 (12), 1-16 (2020). doi: 10.3390/resources9120138.
• [8] H .S. Tu, S.H. Tu, C. Zhang et al., Characteristics of the Roof Behaviours and mine pressure manifestations during the mining of steep coal seam. Arch. Min. Sci. 62 (4), 871-890 (2020).
• [9] P .S. Xie, Y.P. Wu, Deformation and failure mechanisms and support structure technologies for goaf-side entries in steep multiple seam mining disturbances. Arch. Min. Sci. 64 (3), 561-574 (2019). doi: 10.24425/ams.2019.129369.
• [10] Z.Y.Wang, L.M. Dou, J. He et al., Experimental investigation for dynamic instability of coal-rock masses in horizontal section mining of steeply inclined coal seams. Arabian Journal of Geosciences 13, 15 (2020). doi: 10.1007/ s12517-020-05753-5.
• [11] P .S. Xie, Y. Luo, Y.P. Wu et al., Roof Deformation Associated with Mining of Two Panels in Steeply Dipping Coal Seam Using Subsurface Subsidence Prediction Model and Physical Simulation Experiment. Mining, Metall. Explor. 37 (2), 581-591 (2020). doi: 10.1007/s42461-019-00156-x.
• [12] X.P. Lai, H. Sun, P.F. Shan et al., Structure instability forecasting and analysis of giant rock pillars in steeply dipping thick coal seams. Int. J. Miner. Metall. Mater. 22 (12), 1233-1244 (2015). doi: 10.1007/s12613-015-1190-z.
• [13] Y.P. Wu, B.S. Hu, P.S. Xie, A New Experimental System for Quantifying the Multidimensional Loads on an on-Site Hydraulic Support in Steeply Dipping Seam Mining. Exp. Tech. 43 (5), 571-585 (2019). doi: 10.1007/s40799-019- 00304-4.
• [14] Y.D. Zhang, J.Y. Cheng, X.X. Wang et al., Thin plate model analysis on roof break of up-dip or down-dip mining stope. J. Min. Saf. Eng. 27 (4), 487 (2010) (in Chinese).
• [15] J.R. Cao, L.M. Dou, G.A. Zhu et al., Mechanisms of Rock Burst in Horizontal Section Mining of a Steeply Inclined Extra-Thick Coal Seam and Prevention Technology. Energies 13 (22), 6043 (2020). doi: 10.3390/en13226043.
• [16] H .W. Wang, Y.P. Wu, M. Liu et al., Roof-breaking mechanism and stress-evolution characteristics in partial backfill mining of steeply inclined seams. Geomatics, Natural Hazards and Risk 11 (1), 2006-2035 (2020). doi: 10.1080/1 9475705.2020.1823491.
• [17] S.R. Islavath, D. Deb, H. Kumar, Numerical analysis of a longwall mining cycle and development of a composite longwall index. Int. J. Rock Mech. Min. Sci. 89, 43-54 (2016).
• [18] H . Basarir, O.I. Ferid, O. Aydin, Prediction of the stresses around main and tail gates during top coal caving by 3D numerical analysis. Int. J. Rock Mech. Min. Sci. 76, 88-97 (2015). doi: 10.1016/j.ijrmms.2015.03.001.
• [19] J.A. Wang, J.L. Jiao, Criteria of support stability in mining of steeply inclined thick coal seam. Int. J. Rock Mech. Min. Sci. 82, 22-35 (2016). doi: 10.1016/j.ijrmms.2015.11.008.
• [20] W.Y. Lv, Y.P. Wu, M. Liu et al., Migration law of the roof of a composited backfilling longwall face in a steeply dipping coal seam. Minerals 9 (3) (2019). doi: 10.3390/min9030188.
• [21] C.F. Huang, Q. Li, S.G.Tian, Research on prediction of residual deformation in goaf of steeply inclined extra- thick coal seam. PLoS ONE 15, 1-14 (2020). doi: 10.1371/journal.pone.0240428.
• [22] Y.C. Yin, J.C. Zou, Y.B. Zhang et al., Experimental study of the movement of backfilling gangues for goaf in steeply inclined coal seams. Arabian Journal of Geosciences 11 (12) (2018). doi: 10.1007/s12517-018-3686-0.
• [23] G .S.P Singh, U.K. Singh, Prediction of caving behavior of strata and optimum rating of hydraulic powered support for longwall workings. Int. J. Rock Mech. Min. Sci. 47, 1-16 (2010).
• [24] P .S. Xie, Y.Y. Zhang, S.H. Luo et al., Instability Mechanism of a Multi-Layer Gangue Roof and Determination of Support Resistance Under Inclination and Gravity. Mining, Metall. Explor. 37 (5), 1487-1498 (2020). doi: 10.1007/ s42461-020-00252-3.
• [25] G .J. Wu, W.D. Chen, S.P. Jia et al., Deformation characteristics of a roadway in steeply inclined formations and its improved support. Int. J. Rock Mech. Min. Sci. 130, 104324 (2020). doi: 10.1016/j.ijrmms.2020.104324.
• [26] Y.Q. Long, Numerical computation of beam on elastic foundation. People’s Education Press, Beijing (1981).

Uwagi

PL

Opracowanie rekordu ze środków MNiSW, umowa Nr 461252 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2021)