An investigation of longwall failure using 3D numerical modelling – A case study at a copper mine

Nguyen, Phu Minh Vuong; Olczak, Tomasz; Rajwa, Sywester

doi:10.2478/sgem-2021-0019

Abstract

It is well-known that the longwall mining method (with roof caving) is widely used in underground mining extraction for bedded deposits (e.g. coal) due to its numerous advantages. Generally, this method is not commonly applied for ore deposits such as copper deposit. In Poland, the longwall mining method has been tested for thin copper deposits at the Polkowice-Sieroszowice copper mine (KGHM). Various failure modes were observed during longwall operation in the 5A/1 panel. This paper aims to examine these occurred failures. To do so, an analysis has been conducted using 3D numerical modelling to investigate the failure mode and mechanism. Based on the 3D numerical modelling results with extensive in situ measurements, causes of failure are determined and practical recommendations for further copper longwall operations are presented.

References

Butra J, Dębkowski R, Matusz C, Serafin M. Research on the behavior of the rock mass during the experimental exploitation with the longwall method in the A5/1, Polkowice-Sieroszowice copper mine. CUPRUM – Scientific and Technical Journal of Ore Mining, V. 1 (74) 2015, pp. 23–40 (in Polish).
Search in Google Scholar Back to article
Konopko W, Piernikarczyk A. Concept of the extraction technology for thin copper deposits. CUPRUM – CUPRUM – Scientific and Technical Journal of Ore Mining, V. 4 (73) 2014, pp. 17–33 (in Polish).
Search in Google Scholar Back to article
Ziętkowski L, Młynarczyk J. Mechanical mining of hard rock using shearer in the KGHM copper mines. Inżynieria Maszyn 2014, V 19 (2) (in Polish).
Search in Google Scholar Back to article
FLAC3D, Version 5.0, Itasca Consulting Group Inc., Minneapolis (2012); software available at www.itascacg.com.
Search in Google Scholar Back to article
Wang JC, Wang ZH. Systematic principles of surrounding rock control in longwall mining within thick coal seams. Int. J. of Min. Sci. and Technol. 2018. V. 29 (1), pp. 65–71. DOI: 10.1016/j.ijmst.2018.11.014.
Open DOI Search in Google Scholar Back to article
Wang JC, Yang SL, Kong DZ. Failure mechanism and control technology of longwall coalface in large-cutting-height mining method. Int. J. Min. Sci. Technol. 2015, 26 (1), pp. 111–118. DOI: 10.1016/j.ijmst.2015.11.018.
Open DOI Search in Google Scholar Back to article
Bai QS, Tu SH, Li ZX, Tu HS. Theoretical analysis on the deformation characteristics of coal wall in a longwall top coal caving face. Int. J. Min. Sci. Technol. 2015, 25 (2), pp. 199–204. DOI: 10.1016/j.ijmst.2015.02.006.
Open DOI Search in Google Scholar Back to article
Bai QS, Tu SH, Chen M, Zhang C. Numerical modelling of coal wall spall in a longwall face. Int. J. of Rock Mech. and Min. Sci. 2016, V. 88, pp. 242–253. DOI: 10.1016/j.ijrmms.2016.07.031.
Open DOI Search in Google Scholar Back to article
Li XM, Wang ZH, Zhang JW. Stability of roof structure and its control in steeply inclined coal seams. Int. J. Min. Sci. Technol. 2017, 27 (2), pp. 359–364. DOI: 10.1016/j.ijmst.2017.01.018.
Open DOI Search in Google Scholar Back to article
Xin YJ, Gou PF, Ge FD. Analysis of stability of support and surrounding rock in mining top coal of inclined coal seam. Int. J. Min. Sci. Technol. 2014, 24 (1), pp. 63–68. DOI: 10.1016/j.ijmst.2013.12.011.
Open DOI Search in Google Scholar Back to article
Prusek S, Rajwa S, Wrana A, Krzemień A. Assessment of roof fall risk in longwall coal mines, International Journal of Mining, Reclamation and Environment 2017, 31:8, 558–574. DOI: 10.1080/17480930.2016.1200897.
Open DOI Search in Google Scholar Back to article
Masny W. Powered support in dynamic load conditions – numerical analysis. Archives of Mining Sciences 2020, Vol. 65 No 3, s.453–468. DOI: 10.24425/ams.2020.134129.
Open DOI Search in Google Scholar Back to article
Islavath SR, Deb D, Kumar H. Life cycle analysis and damage prediction of a longwall powered support using 3D numerical modelling techniques. Arab. J. of Geosci. 2019, 12:441. DOI: 10.1007/s12517-019-4574-y.
Open DOI Search in Google Scholar Back to article
Rajwa S, Janoszek T, Prusek S. Influence of canopy ratio of powered roof support on longwall working stability – A case study. Int. J. of Min. Sci. and Technol. 2019, 29(4). DOI: 10.1016/j.ijmst.2019.06.002.
Open DOI Search in Google Scholar Back to article
Witek M, Prusek S. Numerical calculations of shield support stress based on laboratory test results. Computers and Geotechnics 2016, 72:74–88. DOI: 10.1016/j.compgeo.2015.11.007.
Open DOI Search in Google Scholar Back to article
Bai QS, Tu SH, Zhang XG. Numerical modelling on brittle failure of coal wall in longwall face – a case study. Arab. J. Geosci. 2014, 7: 5067–5080. DOI: 10.1007/s12517-013-1181-1.
Open DOI Search in Google Scholar Back to article
Verma AK, Deb D. Numerical Analysis of an Interaction between Hydraulic-Powered Support and Surrounding Rock Strata. Int. J. of Geomech. 2013, V. 13 (2). DOI: 10.1061/(ASCE)GM.1943-5622.0000190.
Open DOI Search in Google Scholar Back to article
Singh GSP, Singh UK. Prediction of caving behaviour of strata and optimum rating of hydraulic powered support for longwall workings. Int. J. of Rock Mech.and Min. Sci. 2010, 47(1): 1–16. DOI: 10.1016/j.ijrmms.2009.09.001.
Open DOI Search in Google Scholar Back to article
Trueman R, Lyman G, Cocker A. Longwall roof control through a fundamental understanding of shield–strata interaction. International Journal of Rock Mechanics and Mining Sciences 2009, 46(2): 371–380. DOI: 10.1016/j.ijrmms.2008.07.003.
Open DOI Search in Google Scholar Back to article
Biliński A. Method of selection of longwall face and roadway supports for the panelling conditions; 2005.
Search in Google Scholar Back to article
Janoszek T. The Assessment of longwall working stability based on the Mohr-Coulomb stress criterion – Numerical Analysis. Archives of Mining Sciences 2020, V. 65 (3), pp. 493–509. DOI: 10.24425/ams.2020.134131.
Open DOI Search in Google Scholar Back to article
Song G, Chugh YP, Wang J. A numerical modelling study of longwall face stability in mining thick coal seams in Chin. Int. J. Mining and Mineral Engineering 2017, Vol. 8, No. 1, pp.35–55. DOI: 10.1504/IJMME.2017.10003216.
Open DOI Search in Google Scholar Back to article
Cai M, Morioka H, Kaiser PK, Tasaka Y, Kurose H, Minami M, Maejima T. Back-analysis of rock mass strength parameters using AE monitoring data. Int. J. of Rock Mech. and Min. Sci. 2007, V. 44 (4), pp. 538–549. DOI: 10.1016/j.ijrmms.2006.09.012.
Open DOI Search in Google Scholar Back to article
Gioda G, Sakurai S. Back-analysis procedures for the interpretation of field measurements in geomechanics. Int. J. Numer. Anal. Methods Geomech., 1987, 11, pp. 555–583. DOI: 10.1002/nag.1610110604.
Open DOI Search in Google Scholar Back to article
Kaiser PK, Zou D, Lang PA. Stress determination by back-analysis of excavation-induced stress changes—a case study. Rock Mech. Rock Eng. 1990, 23 (3), pp. 185–200. DOI: 10.1007/BF01022953.
Open DOI Search in Google Scholar Back to article
Sakurai S, Akutagawa S, Takeuchi K, Shinji M, Shimizu N. Back-analysis for tunnel engineering as a modern observational method. Tunnelling Underground Space Technology. 2003, 18 (2), pp. 185–196. DOI: 10.1016/S0886-7798(03)00026-9.
Open DOI Search in Google Scholar Back to article
Ceryan N, Kesimal A, Ceryan S. Chapter 13 - Probabilistic Analysis Applied to Rock Slope Stability: A Case Study From Northeast Turkey. Integrating Disaster Science and Management Global Case Studies in Mitigation and Recovery 2018 Ed. P. Samui, D. Kim, C. Ghosh, pp. 221–261.
Search in Google Scholar Back to article
Bakhtiyari E, Almasi A, Cheshomi A, Hassanpour J. Determination of Shear Strength Parameters of Rock Mass using Back Analysis Methods and Comparison of Results with Empirical Methods. EJERS, European Journal of Engineering Research and Science 2017, Vol. 2, No. 11. DOI: 10.24018/ejers.2017.2.11.518.
Open DOI Search in Google Scholar Back to article
Kim YT, Lee SR. An equivalent model and back-analysis technique for modelling in situ consolidation behavior of drainage-installed soft deposits. Computers and Geotechnics 1997, Volume 20, Issue 2, pp. 125–142. DOI: 10.1016/S0266-352X(96)00016-X.
Open DOI Search in Google Scholar Back to article
Wu Y, Yuan H, Zhang B, Zhang Z, Yu Y. Displacement-Based Back-Analysis of the Model Parameters of the Nuozhadu High Earth-Rockfill Dam. Scientific World Journal 2014, No: 292450. DOI: 10.1155/2014/292450.
Open DOI Search in Google Scholar Back to article
Fakhimi A, Salehi D, Mojtabai N. Numerical back analysis for estimation of soil parameters in the Resalat Tunnel project. Tunnelling and Underground Space Technology 2004, 19(1):57–67. DOI: 10.1016/S0886-7798(03)00087-7.
Open DOI Search in Google Scholar Back to article
Pu Y, Apel DB, Prusek S, Walentek A, Cichy T. Back-analysis for initial ground stress field at a diamond mine using machine learning approaches. Nat. Hazards 2020. DOI: 10.1007/s11069-020-04304-1.
Open DOI Search in Google Scholar Back to article
Cichy T, Prusek S, Świątek J, Apel D, Pu Y. Use of Neural Networks to Forecast Seismic Hazard Expressed by Number of Tremors Per Unit of Surface. Pure Appl. Geophys., 2020. DOI: 10.1007/s00024-020-02602-0.
Open DOI Search in Google Scholar Back to article
Sakurai S. Back analysis in Rock Engineering. International society for Rock mechanics. ISRM book series, 2017, p. 226.
Search in Google Scholar Back to article
Hoek E, Brown ET. Practical estimates of rock mass strength. Int. J. of Rock Mech. and Min. Sci. 1997, 34, 8, pp. 1165–1186. DOI: 10.1016/S1365-1609(97)80069-X.
Open DOI Search in Google Scholar Back to article
Wilson AH. A method of estimating the closure and strength of lining required in drivages surrounded by a yield zone. Int. J. Rock Mech. Min. Sci. and Geomech. Abstr., 1980, p. 349–355. DOI: 10.1016/0148-9062(80)90518-5.
Open DOI Search in Google Scholar Back to article
Schullera H, Schweiger HF. Application of a multilaminate model to simulation of shear band formation in NATM-tunnelling. Comput. Geotech. 2002, 29(7): 501–524. DOI: 10.1016/S0266-352X(02)00013-7.
Open DOI Search in Google Scholar Back to article
Mortazavi A, Hassani FP, Shabani M. A numerical investigation ofrock pillar failure mechanism in underground openings. Comput. Geotech. 2009, 36(5): 691–697. DOI: 10.1016/j.compgeo.2008.11.004.
Open DOI Search in Google Scholar Back to article
Edelbro C. Different approaches for simulating brittle failure in two hard rock mass cases: a parametric study. Rock Mech. Rock Eng., 2010, 43(2):151–165. DOI: 10.1007/s00603-008-0025-x.
Open DOI Search in Google Scholar Back to article
Wang SY, Sloan SW, Huang ML, Tang CA. Numerical study of failure mechanism of serial and parallel rock pillars. Rock Mech. Rock Eng., 2011a, 44:179–198. DOI: 10.1007/s00603-010-0116-3.
Open DOI Search in Google Scholar Back to article
Wang SL, Zheng H, Li CG, Ge XR. A finite element implementation of strain-softening rock mass. Int. J. Rock Mech. Min. Sci., 2011b, 48:67–76. DOI: 10.1016/j.ijrmms.2010.11.001.
Open DOI Search in Google Scholar Back to article

An investigation of longwall failure using 3D numerical modelling – A case study at a copper mine

Abstract

Paradigm

My account