Jarufe, J & Vasquez, P 2008, 'Mine-Scale 3D Stress Model for the New Mine Level Project, El Teniente Mine, Codelco, Chile', in Y Potvin, J Carter, A Dyskin & R Jeffrey (eds), Proceedings of the First Southern Hemisphere International Rock Mechanics Symposium
, Australian Centre for Geomechanics, Perth, pp. 231-242.
For the development of the pre-feasibility study for the New Mine Level Project (NML) carried out by Codelco Chile Project Corporate Vice-Presidency, it is fundamental to have numerical models that allow estimating the stress state for the various mining options under study in a quick, simple and reliable manner. For this reason, a simplified mine scale model was created to analyse geomechanical issues that go from drift scale (overbreaking), large excavations (caverns) to mine scale issues (caving front geometries, mining macro-sequences, sector interactions). The software tool preferred was Map3D (Mine Modelling Pty Ltd).
The boundary conditions used as the base for the Map3D modelling tool correspond to the geometry to be analysed and the pre-mining stress state in the zone of interest. To estimate this latter condition, the Conceptual Stress Model (Karzulovic et al., 2006) information was used and originally, the stress orientation expected for that zone based on Plate Tectonics (east-west trending) was considered. To test the model’s efficacy, various validation exercises were carried out: comparison of the model’s results with field stress measurement for different years, between the abutment stress zone predicted by the model and the one observed in the field, and the model-predicted overbreak versus the actual overbreak obtained through field surveys.
It can be concluded that the model created fulfils the reliability levels that have been historically used for mine-scale models in a pre-feasibility engineering stage. The validated and calibrated boundary conditions can be applied both for mine-scale and drift-scale models, with error values of 40% compared to stress measurements and 20% when compared to field-observed damage.
Celhay, F., Pereira, J. and Burgos, L. (2005) Geology and Resources for the New Mine Level, Pre-feasibility Engineering stage, SGL-I-030/05. Internal report Codelco–Chile.
Hoek, E., Carranza-Torres, B. and Corkum, B. (2006) El Criterio de rotura de Hoek–Brown, Edición 2002.
Itasca S.A. (1998) Updating of Mine-Scale 3D Numerical Models. Prepared for and funded by the Engineering and Planning, MINCO, Codelco Chile – El Teniente Division.
Itasca S.A. (2007) 3D Stress Model and Mining Macro Sequences for the New Mine Level Project, Codelco Chile - El Teniente Division, Study NNM-E-02. Prepared for and funded by the New Mine Level Project, VCP.
Karzulovic, A., Cavieres, P. and Gonzales, G. (2006) El Teniente Mine Conceptual Field Stress Model, Study DT-CG-2006. Prepared for and funded by the New Mine Level Project, VCP.
Stress Map: web site www.wsm.physik.uni.karlsruhe.de
Vásquez, P., Cavieres, P. and Jarufe, J. (2008a) Report NNM-ICO-GEM-INF-008, 3D Stress Model for the New Mine Level Project (Map3D).
Vásquez, P., Cavieres, P., Jarufe, J., Bahamondes, C. and Valdivia, R. (2008b) Report NNM-ICO-GEM-INF-010, Geomechanical recommendation for the size, shape and decoupling of caving front. New Mine Level Project.
Wiles, T. (2007) Map3D Manual.
Wiles, T. (2006) Map3D Course Notes, © Mine Modelling Pty Ltd 2006.