Abstract
To study the temporal-spatial evolution of ground pressure at short-distance coal seams, this paper studied the displacement law of overlying strata and the temporal-spatial evolution of ground stress by analog simulation experiments. The results show when the upper coal seam is mined, overlying strata of the stope form three zones: the caved zone, the fractured zone and the bending subsidence zone. The caved zone which subsided in the largest quantity showed an irregular subsidence curve. The fractured zone where the maximum subsidence amounts are basically located in the middle of the goaf had approximately parabolic subsidence curves. The bending subsidence zone underwent the least subsidence as it was controlled by the key layer. In the coal mining process, stress concentrated in front of both the opening-off cut and the working face. When the working face advanced to 150 m, bearing stress of the opening-off cut and the working face was up to 20 MPa, with a stress concentration coefficient of 1.98. When the lower coal seam was mined, the immediate roof kept caving as the mining proceeded, with no obvious initial weighting or periodic weighting in the main roof. Only the roof stress within the mining area demonstrated greater fluctuations as the mining moved on. Pressures at the opening-off cut and the stopping line remained high in the whole process, so it is suggested to pay special attention to pressure detection during the first cut and make sure the roof is well supported for the mining of lower coal seam.
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References
Cheng YP, Yu QX, Yuan L (2003) Gas extraction techniques and movement properties of long distance and pressure relief rock mass upon exploited coal seam. J Liaoning Tech Univ 4:483–486
Guo H et al (2012) Mining-induced strata stress changes, fractures and gas flow dynamics in multi-seam longwall mining. I. Int J Rock Mech Min Sci 54:129–139
Li SG et al (2015) Research on influence of mining height on mining fissure evolution. Min Saf Environ Prot 05:25–28
Ma ZG et al (2008) Rock mass deformation characteristics for coal mining at remote lower protective seam. J Min Saf Eng 3:235–257
Miao XX et al (1997) Research on broken expand and press solid characteristics of rocks and coals. J Exp Mech 3:3394–3400
Ren WZ et al (2010) Model experimental research on deformation and subsidence characteristics of ground and wall rock due to mining under thick overlying terrane. Int J Rock Mech Min Sci 47:614–624
Singh GSP, Singh UK (2009) A numerical modeling approach for assessment of progressive caving of strata and performance of hydraulic powered support in longwall workings. Comput Geotech 36:1142–1156
Unver B, Yasitli NE (2006) Modelling of strata movement with a special reference to caving mechanism in thick seam coal mining. Int J Coal Geol 66:227–252
Wang SH, Ren ZM, Dou ZR (2012) The influence of surface subsidence in coal mine goaf and its countermeasures. Min Saf Environ Prot 06:68–69 + 72
Xie HP et al (1999) Research on the fractal effects of crack network in overburden rock stratum. Chin J Rock Mech Eng 2:147–151
Xie HP et al (2001) Study on generation of rock fracture surfaces by using fractal interpolation. Int J Solids Struct 32:5765–5787
Xie WB, Chen XX, Zheng BS (2005) Numerical simulation study and analysis of mining projects. China University of Mining and Technology Press, Xuzhou
Xu NZ, Han L (2010) Pressure-relief effect of coal rock body of long distance lower protective seam mined based on FLAC3D. J Coal Sci Eng 16:341–346
Yan LZ (2009) Use of similar-simulation physical model for studing underground pressure. Min Saf Environ Prot 04:20–22 +34+91
Yang W et al (2011) Mechanism of strata deformation under protective seam and its application for relieved methane control. Int J Coal Geol 85:300–306
Yavuz H (2004) An estimation method for cover pressure re-establishment distance and pressure distribution in the goaf of longwall coal mines. Int J Rock Mech Min Sci 41:193–205
Yu XY (2003) Mining damages and environment protection. Coal Industry Publishing Press, Beijing
Yu QX, Cheng YP (2012) Mine gas prevention and control. China University of Mining and Technology Press, Xuzhou
Zhang ZH et al (2012) Simulation research on the influence of eroded primary key strata on dynamic strata pressure of shallow coal seams in gully terrain. Int J Min Sci Technol 22(1):51–55
Zhu WS et al (2011) Quasi-three-dimensional physical model tests on a cavern complex under high in-situ stresses. Int J Rock Mech Min Sci 48:199–209
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The helpful comments by the anonymous reviewer are highly appreciated.
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This work is financially supported by the Education Department of Fujian Province (No. JAT190758) and national training programs of innovation and entrepreneurship for undergraduates (NO.201811312011).
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Responsible Editor: Murat Karakus
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Liu, Q., Huang, J., Guo, Y. et al. Research on the temporal-spatial evolution of ground pressure at short-distance coal seams. Arab J Geosci 13, 1014 (2020). https://doi.org/10.1007/s12517-020-05801-0
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DOI: https://doi.org/10.1007/s12517-020-05801-0