Catalan, A & Suarez, C 2010, 'Geotechnical characterisation — Cadia East panel caving project, New South Wales, Australia', in Y Potvin (ed.), Caving 2010: Proceedings of the Second International Symposium on Block and Sublevel Caving
, Australian Centre for Geomechanics, Perth, pp. 371-387, https://doi.org/10.36487/ACG_rep/1002_26_Catalan1
The geotechnical and structural characterisation of the rock mass is a fundamental tool for the development of any mining project. This knowledge allows the generation of reliable models capable of representing anticipated geotechnical conditions of caving processes and for prediction of probable behaviour at distinct depths and geometries.
Cadia East underground project will be one of the largest and deepest panel caving operations in Australia. The first extraction level will be situated about 1,200 m below surface and a second lift located about 1,400 m shall be brought into operation simultaneously with the first lift. It has dimensions over 250 m wide, with a strike length in excess of 1,200 m and a vertical extent of 800 m could classify this orebody as a world-class mining project. Due to these characteristics, during to the last five years extensive and careful geological, metallurgical and geotechnical studies have been carried out mainly based on more than 400 km of drillholes and about 900 m of bulk sample drive.
This paper will describe the geotechnical process which has been implemented at Cadia East project and how geological and geotechnical information has been assembled and implemented in a powerful geotechnical platform. This structure has incorporated a robust geotechnical database which includes lithologies, alterations, structural condition and geotechnical rock mass characterisation, allowing for the development of a 3D geotechnical model. Also and from these sources, the critical geotechnical parameters have be derived for use in assessing rock mass quality through standard classification methodologies such as rock mass rating (RMR) and mining rock mass rating (MRMR) or the geological strength index (GSI).
Finally, this geotechnical process has added an adequate level of belief in order to support all necessary geotechnical studies that support the prefeasibility phase of what will become the largest and deepest panel cave in Australia.
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