Abstract
The mining-induced strata movement and surface subsidence are closely related to the dip angle of coal seam. However, most surface subsidence prediction methods are empirical, and only suitable for nearly flat coal seam mining. In this paper, a new theoretical method is proposed to predict the strata movement boundary and surface subsidence caused by inclined coal seam mining, which considers the influence of key strata, rock quality and coal seam dip angle. The strata movement caused by inclined coal seam mining is generalized and described by three models: analogous hyperbola model (AHM), analogous hyperbola-funnel model (AHFM), and analogous funnel model (AFM). Considering the rock quality of roof and floor strata, the rock mass rating system is adopted to calculate the surface maximum subsidence and its location. Additionally, the distinct element method was used to assess the performance of the theoretical models. The numerical simulation results match well with theoretical predictions of strata movement boundary and surface subsidence. It is discovered that the appearance of surface subsidence troughs is obviously asymmetric. As the dip angle increases, the surface maximum subsidence decreases and its location is laterally displaced. When the dip angle is greater than 50°, the double subsidence troughs can be visualized clearly. Furthermore, the theoretical predictions of surface subsidence are verified by field measurements of two cases. As a result, the theoretical predictions of surface subsidence are greatly improved by comparing with the empirical method.
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Abbreviations
- E :
-
Young’s modulus [GPa]
- γ :
-
Volumetric weights [kg/m3]
- [σ t]:
-
Tensile strength [MPa]
- c :
-
Cohesion [MPa]
- M :
-
Thickness of coal seam [m]
- h PKS :
-
Thickness of PKS [m]
- L PKS :
-
Length of broken PKS blocks [m]
- H PKS :
-
Depth of primary key stratum [m]
- W s :
-
Surface subsidence [m]
- W max :
-
Maximum subsidence of PKS [m]
- β lower :
-
Dip angle of lower sliding plane [°]
- β upper :
-
Dip angle of upper sliding plane [°]
- θ upper :
-
Upper goaf angle [°]
- θ lower :
-
Lower goaf angle [°]
- β f :
-
Dip angle of floor sliding plane [°]
- S r/f :
-
Cavity area of roof/floor [m2]
- ks:
-
Shear stiffness [GPa/m]
- kn:
-
Normal stiffness [GPa/m]
- U :
-
Water force acting on sliding plane [kN]
- H b :
-
Strata thickness between PKS and coal seam [m]
- η r /f :
-
Roof/floor convergence factors due to dip angle [-]
- κ r /f :
-
Roof/floor rock mass quality factors [-]
- ∆ r/f :
-
Laterally displaced distance of roof/floor maximum subsidence [m]
- h :
-
Thickness of rock layer [m]
- L :
-
Length of broken block [m]
- q :
-
Load on rock layer [kN/m]
- φ :
-
Friction angle [°]
- α :
-
Dip angle of coal seam [°]
- H 0 :
-
Average depth of mining face [m]
- d :
-
Excavation width [m]
- W :
-
Weight of sliding rock masses [kN]
- A :
-
Area of potential sliding plane [m2]
- F s :
-
Safety factor [-]
- ρ :
-
Density [kg/m3]
- ψ :
-
Dilation angle [°]
- φ m :
-
Friction angle of coal seam [°]
- θ 0 :
-
Goaf angle due to horizontal mining [°]
- θ r :
-
Influence transfer angle of roof strata [°]
- K p :
-
Bulking factor [–]
- υ :
-
Poisson’s ratio [–]
- q s :
-
Subsidence coefficient [–]
- V :
-
Water force acting in tension crack [kN]
References
Alejano LR, RamõÂrez-Oyanguren P, Taboada J (1999) FDM predictive methodology for subsidence due to flat and inclined coal seam mining. Int J Rock Mech Min Sci 36(4):475–491. https://doi.org/10.1016/S0148-9062(99)00022-4
Alvarez-Fernandez MI, Gonzalez-Nicieza C, Menendez-Dıaz TA, Alvarez-Vigil AE (2005) Generalization of the n–k influence function to predict mining subsidence. Eng Geol 80(1–2):1–36. https://doi.org/10.1016/j.enggeo.2005.02.004
Asadi A, Shahriar K, Goshtasbi K, Najm K (2005) Development of a new mathematical model for prediction of surface subsidence due to inclined coal-seam mining. J S Afr I Min Metall 105(1):15–20
Bieniawski ZT (1973) Engineering classification of jointed rock masses. Trans S Afr Inst Civ Eng 15:335–344
Cai LL, Mo XH, Wu K, Guo ZZ (2016) Steep coal seam mining subsidence prediction considering floor strata movement. Chin J Undergr Space Eng 12(4):1048–1054 (in Chinese)
Cheng GW, Ma TH, Tang CA, Liu HY, Wang SJ (2017) A zoning model for coal mining - induced strata movement based on microseismic monitoring. Int J Rock Mech Min Sci 94:123–138. https://doi.org/10.1016/j.ijrmms.2017.03.001
Cui XM, Miao XX, Wang JA, Yang S, Liu HD, Song YQ, Liu H, Hu XK (2000) Improved prediction of differential subsidence caused by underground mining. Int J Rock Mech Min Sci 37(4):615–627. https://doi.org/10.1016/S1365-1609(99)00125-2
Dai HY, Wang JZ, Cai MF, Wu LX, Guo ZZ (2002) Seam dip angle based mining subsidence model and its application. Int J Rock Mech Min Sci 39(1):115–123. https://doi.org/10.1016/S1365-1609(02)00008-4
Dai HY, Lian XG, Liu JY, Cai YF (2010) Model study of deformation induced by fully mechanized caving below a thick loess layer. Int J Rock Mech Min Sci 47(6):1027–1033. https://doi.org/10.1016/j.ijrmms.2010.06.005
Dai HY, Yi SH, Guo JT, Yan YG, Liu AJ (2013) Prediction method for surface movements and deformation induced by extra-thick steeply inclined coal seam horizontal slice mining. J China Coal Soc 21(3):225–230. https://doi.org/10.13225/j.cnki.jccs.2013.08.011 (in Chinese)
Daupley X, Cuche H, Ghoreychi M (2005) Typology of strata movement related to old solution mining of salt at Sarralbe (Lorraine, France). In: Symposium post mining, Nancy, France
Gao FQ, Stead D, Coggan J (2014) Evaluation of coal longwall caving characteristics using an innovative UDEC Trigon approach. Comput Geotech 55:448–460. https://doi.org/10.1016/j.compgeo.2013.09.020
Ghabraie B, Ren G, Barbato J, Smith JV (2017) A predictive methodology for multi-seam mining induced subsidence. Int J Rock Mech Min Sci 93:280–294. https://doi.org/10.1016/j.ijrmms.2017.02.003
Gonzalez-Nicieza C, Alvarez-Fernandez MI, Menendez-Dıaz TA, Alvarez-Vigil AE (2005) The new three-dimensional subsidence influence function denoted by n–k–g. Int J Rock Mech Min Sci 42:372–387. https://doi.org/10.1016/j.ijrmms.2004.12.003
Israelsson JI (1996) Short descriptions of UDEC and 3DEC. Dev Geotech Eng 79:523–528
Itasca (2014) Universal distinct element code (UDEC version 6.0) manual. Itasca Consulting Group Inc., Minneapolis, MN
Jing L (2003) A review of techniques, advances and outstanding issues in numerical modelling for rock mechanics and rock engineering. Int J Rock Mech Min Sci 40:283–353. https://doi.org/10.1016/S1365-1609(03)00013-3
Ju JF, Xu JL (2015) Surface stepped subsidence related to top - coal caving longwall mining of extremely thick coal seam under shallow cover. Int J Rock Mech Min Sci 78:27–35. https://doi.org/10.1016/j.ijrmms.2015.05.003
Kelly M, Luo X, Craig S (2002) Integrating tools for longwall geomechanics assessment. Int J Rock Mech Min Sci 39(5):661–676. https://doi.org/10.1016/S1365-1609(02)00063-1
Li HZ, Zha JF, Guo GL (2019) A new dynamic prediction method for surface subsidence based on numerical model parameter sensitivity. J Clean Prod 233:1418–1424. https://doi.org/10.1016/j.jclepro.2019.06.208
Litwiniszyn J (2014) Stochastic methods in mechanics of granular bodies. Springer, New York
Malinowska A, Hejmanowski R (2010) Building damage risk assessment on mining terrains in Poland with GIS application. Int J Rock Mech Min Sci 47(2):238–245. https://doi.org/10.1016/j.ijrmms.2009.09.009
Miao XX, Cui XM, Wang JA, Xu JL (2011) The height of fractured water-conducting zone in undermined rock strata. Eng Geol 120(1–4):32–39. https://doi.org/10.1016/j.enggeo.2011.03.009
Peng SS (1992) Surface subsidence engineering. Society for Mining, Metallurgy and Exploration Inc., USA
Qian MG, Miao XX, Xu JL (1996) Theoretical study of key stratum in ground control. J China Coal Soc 21(3):225–230. https://doi.org/10.13225/j.cnki.jccs.1996.03.001 (in Chinese)
Ren G, Whittaker BN, Reddish DJ (1989) Mining subsidence and displacements prediction using infuence functions methods for steep seams. Min Sci Technol 8:235–252
Sun YJ, Zuo JP, Karakus M, Wang JT (2019) Investigation of movement and damage of integral overburden during shallow coal seam mining. Int J Rock Mech Min Sci 117:63–75. https://doi.org/10.1016/j.ijrmms.2019.03.019
Sun YJ, Zuo JP, Karakus M, Wen JH (2020) A novel method for predicting movement and damage of overburden caused by shallow coal mining. Rock Mech Rock Eng 53(4):1545–1563. https://doi.org/10.1007/s00603-019-01988-1
Torano J, Rodriguez R, Ramirez-Oyanguren P (2000) Probabilistic analysis of subsidence-induced strains at the surface above steep seam mining. Int J Rock Mech Min Sci 37(7):1161–1167. https://doi.org/10.1016/S1365-1609(00)00046-0
Tu HS, Tu SH, Yuan Y, Wang FT, Bai QS (2015) Present situation of fully mechanized mining technology for steeply inclined coal seams in China. Arab J Geosci 8:4485–4494. https://doi.org/10.1007/s12517-014-1546-0
Wang SF, Li XB, Wang DM (2016) Void fraction distribution in overburden disturbed by longwall mining of coal. Environ Earth Sci 75(2):151. https://doi.org/10.1007/s12665-015-4958-6
Wang SF, Li XB, Wang SY (2017) Separation and fracturing in overlying strata disturbed by longwall mining in a mineral deposit seam. Eng Geol 226:257–266. https://doi.org/10.1016/j.enggeo.2017.06.015
Whittaker BN, Reddish DJ (1989) Subsidence: occurrence, prediction and control. Elsevier, Nottingham, pp 15–113
Xie PS, Luo Y, Wu YP, Gao XC, Luo SH, Zeng YF (2020) Roof deformation associated with mining of two panels in steeply dipping coal seam using subsurface subsidence prediction model and physical simulation experiment. Min Metall Explor 37:581–591. https://doi.org/10.1007/s42461-019-00156-x
Xu JL, Qian MG (2000) Research on the surface movement effects of key stratum movement. J China Coal Soc 25(2):122–126. https://doi.org/10.13225/j.cnki.jccs.2000.02.003 (in Chinese)
Acknowledgements
This study was funded by the Beijing Outstanding Young Scientist Program (BJJWZYJH01201911413037), National Natural Science Foundation of China (Grants No: 52004287; 51622404; 41877257), and Shannxi Coal Group Key Project (2018SMHKJ-A-J-03).
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Sun, Y., Zuo, J., Karakus, M. et al. A New Theoretical Method to Predict Strata Movement and Surface Subsidence due to Inclined Coal Seam Mining. Rock Mech Rock Eng 54, 2723–2740 (2021). https://doi.org/10.1007/s00603-021-02424-z
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DOI: https://doi.org/10.1007/s00603-021-02424-z