Empirical and numerical assessment of two extended stopes for dilution estimation in an underground mine

doi:10.36487/ACG_repo/2465_75

Authors: Santos Chauca, AI; Shnorhokian, S; Kumral, M

Download Paper

Open access courtesy of:

DOI https://doi.org/10.36487/ACG_repo/2465_75

Cite As:
Santos Chauca, AI, Shnorhokian, S & Kumral, M 2024, 'Empirical and numerical assessment of two extended stopes for dilution estimation in an underground mine', 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. 1151-1164, https://doi.org/10.36487/ACG_repo/2465_75

Download citation as: ris bibtex endnote text Zotero

Abstract:
Over the decades, several empirical and analytical approaches have been developed to assess the stability of underground excavations. For stope design, the stability graph method is commonly used for preliminary sizing assessments. The method has been modified by multiple authors over time using extensive databases to adjust the three factors and boundary limits for the stability zones. Based on field observations, the adjustments were made to improve the qualitative representation of rock mass stability and associated risks. Moreover, different applications such as the dilution graph have been developed based on the stability graph method. The overbreak prediction for open stope footwalls and hanging walls can be quantified with this graph. Numerical modelling is another important tool in rock engineering, commonly utilised in conducting complex analyses in mining. The model consists of numerous elements or zones that discretise the rock mass, requiring initial calibration to predict future results. In the stability graph method, the estimation of induced stress for the stability Factor A purely depends on numerical analysis techniques. In the present study, an assessment is developed for the stability of two extended stopes that were extracted in an underground mine. The stope designs were evaluated using the stability graph method and two versions of the dilution graph. Advanced 3D models were constructed for determining Factor A and for assessing the stability of stope surfaces based on a numerical approach. Finally, a comparison was made between the empirical results of the stability graph method and dilution graph, the numerical models, and actual field observations and cavity monitoring survey (CMS) measurements after the extraction of each stope at the mine.

Keywords: ore dilution, stability graph method, 3D modelling, extended stopes

References:

Capes, G & Milne, D 2008, ‘A compilation of dilution graph data for open stope hangingwall design’, 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. 149–162,

Capes, G 2009, Open Stope Hangingwall Design Based on General and Detailed Data Collection in Rock Masses With Unfavourable Hangingwall Conditions, PhD thesis, University of Saskatchewan, Saskatoon.

Clark, L & Pakalnis, R 1997, ‘An empirical design approach for estimating unplanned dilution from open stope hangingwalls and footwalls’, Proceedings of the 99th annual general meeting, Canadian Institute of Mining, Metallurgy and Petroleum, Vancouver.

Hoek, E, Kaiser, PK & Bawden, WF 1995, Support of underground excavations in hard rock, AA Balkema Publishers, Brookfields.

Hutchinson, DJ & Diederichs, MS 1996, Cablebolting in Underground Mines, BiTech Publishers Ltd, Richmond.

Mathews, KE, Hoek, E, Wyllie, DC & Stewart, SBV 1981, Prediction of Stable Excavation Spans for Mining at Depths Below 1000m in Hard Rock, CANMET Report DSS Serial No. OSQ80-00081, DSS File No. 17SQ. 23440-0-9020, Canada Department of Energy Mines and Resources, Ottawa.

Nickson, SD 1992, Cable Support Guidelines For Underground Hard Rock Mine Operations, MASc thesis, University of British Columbia, Vancouver.

Potvin, Y 1988, Empirical Open Stope Design in Canada, PhD thesis, University of British Columbia, Vancouver.

Potvin, Y & Hadjigeorgiou, J 2001, ‘The stability graph method for open stope design’, in Hustrulid & Bullock (eds), Underground Mining Methods, Society of Mining Engineers, pp. 513–520.

Stewart, SBV & Forsyth, WW 1995, ‘The Mathew's method for open stope design’, CIM bulleting, vol. 88, pp. 45–53.

Suorineni, FT 2012, ‘A critical review of the stability graph method for open stope design’, MassMin 2012: 6th International Conference & Exhibition on Mass Mining, Canadian Institute of Mining, Metallurgy and Petroleum, Sudbury,

Vakili, A 2016, ‘An improved unified constitutive model for rock material and guidelines for its application in numerical modelling’, Computers and Geotechnics, vol. 80, pp. 261–282,

© 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