SRK Consulting Russia, Moscow, Russia:

I. S. Livinskiy, Senior Geomechanics Consultant, ilivinsky@srk.ru.com

SRK Consulting Toronto, Totonto, Canada:
A. F. Mitrofanov, Senior Resource Geology Consultant, Candidate of Geological and Mineralogical Sciences

Kazakhmys Corporation, Astana, Kazakhstan:
A. B. Makarov, Geomechanical Expert, Professor, Doctor of Engineering Sciences

A geotechnical model is the basis for any further geotechnical calculations and conclusions as well as the source of input data for slope analysis and selection of mining method and many other parameters. However, the most common practice nowadays is to use oversimplified geological models rather than geotechnical ones. As a result of this, geological and structural parameters of the deposit that often play a key role are ignored in the interpretation and have no effect on further geotechnical analysis. Meanwhile, it has become a standard practice in SRK to engage two technical specialists, a geologist and geotechnical engineer, to work together on a geotechnical model. This tandem approach makes it possible to take into account all important geological features of the deposit, such as faults and structures, main geological units, anisotropy that predetermines geotechnical interpolation parameters, etc. At the same time, participation of a geotechnical engineer in each stage of the analysis enables the model to be focused primarily on the geotechnical aspects. An important stage in the model development is the defi nition of the so-called geological-geotechnical wireframe domains within which the distribution of geotechnically significant numerical parameters appear to be consistent and reasonable. Domain wireframes are then filled with the block model, and numerical geotechnical characteristics of the rock mass are interpolated into each block, taking into account the rock mass geological anisotropy. The resulting model can be further used for all geotechnical calculations as well as we for 2D and 3D modelling. The key advantages of this model include a visual representation of the rock mass condition in various deposit sectors, selection flexibility and optimum number of cross sections required for the analysis as well as the opportunity to perform a 3D stability modelling.

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