Model calibration and seismic potential vulnerability assessment with the mining rock mass seismicity model

Authors: Lachenicht, R; Sharrock, G

Open access courtesy of:

DOI https://doi.org/10.36487/ACG_repo/2465_50

Cite As:
Lachenicht, R & Sharrock, G 2024, 'Model calibration and seismic potential vulnerability assessment with the mining rock mass seismicity model', in P Andrieux & D Cumming-Potvin (eds), Deep Mining 2024: Proceedings of the 10th International Conference on Deep and High Stress Mining, Australian Centre for Geomechanics, Perth, pp. 793-808, https://doi.org/10.36487/ACG_repo/2465_50

Download citation as:   ris   bibtex   endnote   text   Zotero


Abstract:
The mining rock mass seismicity (MRS) model establishes modelled versus observed seismic potential correlation relations used to forecast the future rock mass seismic response to mining. ITASCA’s FLAC3D continuum code calculates the plastic work dissipated throughout the rock mass and along geological structures for each mining extraction increment of a global mine model. The progressive failure and disintegration of the rock mass is modelled with different FLAC3D constitutive models. The understanding of the rock mass and geological structural environment in conjunction with available calibration data forms the foundation of the seismic potential assessment. Confidence associated with the derived calibration relations reflects the understanding and definition of the failure mechanics incorporated into the modelling. This paper extends the MRS model calibration and seismic potential assessment methodology through the incorporation of modelled system response tests to assess the global system’s vulnerability to failure. Strength assumptions are lowered during a model system test, reducing the analysis reliance on the accuracy of the input parameter assumptions. Spatial and temporal comparisons between the base modelled system response, modelled system tests and observed seismicity are used to refine the modelled seismic potential of failure regions. Failure responses identified from modelled calibration system tests can be integrated back into the baseline model, improving the derived calibration relations and model confidence. System tests are further applied to forward analyses to examine the ongoing system vulnerability to failure. The introduction of system tests with bracketing parameter ranges reduces the model reliance on deterministic input parameter assumptions, facilitating the incorporation of additional mitigation strategies for identified system test vulnerabilities associated with a high modelled seismic potential.

Keywords: seismicity, model calibration, seismic potential assessment

References:
Brady, BHG & Brown, ET 2005, Rock Mechanics for Underground Mining, 3rd edn, Kluwer Academic Publishers, Dordrecht.
Brown, ET 2007, Block Caving Geomechanics (The International Caving Study I, 1997-2000), University of Queensland, JKMRC Monograph Series in Mining and Mineral Processing, Volume 3, JKMRC, Indooroopilly.
Castro, LAM, Bewick, RP & Carter, TG 2012, ‘An overview of numerical modelling applied to deep mining’, Innovative Numerical Modeling in Geomechanics, CRC Press, Boca Raton.
Chitombo, G & Pierce, ME 2012, A Practical Guide on the Use of the MMT Tools and Methodologies - Block Panel and Sublevel Caving, report to Mass Mining Technology project.
Cook, NGW, Hoek, E, Pretorius, JPG, Ortlepp, WD & Salamon, MDG 1966, ‘Rock mechanics applied to rockbursts’, Journal of the South African Institute for Mining and Metallurgy, pp. 435–714.
Diederichs, MS 1999, Instability of Hard Rockmasses: The Role of Tensile Damage and Relaxation, PhD thesis, University of Waterloo, Waterloo.
Diederichs, MS 2003, ‘Rock Fracture and collapse under low confinement conditions’, Rock Mechanics and Rock Engineering, vol. 36, no. 5, pp. 339–381.
Hoek, E, Carranza-Torres, C & Corkum, B 2002, ‘Hoek-Brown failure criterion - 2002 edition’, Proceedings of NARMS-TAC Conference, University of Toronto Press, Toronto.
ITASCA 2024, ITASCA Software Guide, version 9.0.169, Minneapolis, .
Jager, AJ & Ryder, JA 1999, A Handbook on Rock Engineering Practice for Tabular Hardrock Mines, Safety in Mines Research Advisory Committee, Johannesburg.
Lorig, L 2000, The Role of Numerical Modelling in Assessing Caveabilty, ITASCA, Minneapolis, report to the International Caving Study.
McGarr, A, Spottiswoode, SM, Gay, NC & Ortlepp, WD 1979, ‘Observations relevant to seismic driving stress, stress drop and efficiency’, Journal of Geophysical Research, vol. 84, pp. 2251–2261.
Mendecki, AJ 2008, ‘Forecasting Seismic Hazard in Mines’, in Y Potvin, J Carter, A Dyskin & R Jeffrey (eds), SHIRMS 2008: Proceedings of the First Southern Hemisphere International Rock Mechanics Symposium, Australian Centre for Geomechanics, Perth, pp. 55–69,
Mendecki, AJ, van Aswegen, G & Mountfort, P 1999, ‘A guide to routine seismic monitoring in mines’, in AJ Jager & JA Ryder (eds), A Handbook on Rock Engineering Practice for Tabular Hard Rock Mines, Creda Communications, Cape Town.
Ortlepp, WD 1997, Rock Fracture and Rockbursts – An Illustrative Study, South African Institute of Mining and Metallurgy, Johannesburg.
Pierce, M 2013, ‘Numerical modeling of rock mass weakening, bulking and softening associated with cave mining’, ARMA eNewsletter, Spring 2013, no. 9.
Sharrock, G 2017, ‘Rock mass damage category relations based on damage observations and bonded block modelling’, unpublished ITASCA memorandum.
Wiles, TD, Lachenicht, R & van Aswegen, G 2001, ‘Integration of deterministic modelling with seismic monitoring for the assessment of rock mass response to mining: Part I Theory’, RaSiM5: Proceedings of the 5th International Symposium on Rockbursts and Seismicity in Mines, South African Institute of Mining and Metallurgy, Johannesburg.
Wiles, TD 2005, ‘Rockburst prediction using numerical modelling—realistic limits for failure prediction accuracy’, in Y Potvin & M Hudyma (eds), RaSiM6: Proceedings of the Sixth International Symposium on Rockburst and Seismicity in Mines Proceedings, Australian Centre for Geomechanics, Perth, pp. 57–63,




© Copyright 2024, Australian Centre for Geomechanics (ACG), The University of Western Australia. All rights reserved.
View copyright/legal information
Please direct any queries or error reports to repository-acg@uwa.edu.au