NorNickel Technical Services LLC, Saint-Petersburg, Russia:

N. O. Soluyanov, Chief Geomechanic, soluyanovno@nornik.ru

NorNickels’ Polar Division, Norilsk, Russia:
A. A. Tsymbalov, Deputy Director of Mining Practice

Siberian Coal Energy Company, Moscow, Russia:
S. V. Kuzmin, Research Manager in Geomechanics, Mine Planning Directorate, Candidate of Engineering Sciences

NN Development LLC, Moscow, Russia:
A. A. Davydov, Head of Skalisty Mine Integrated Design and Development Office

A geomechanical model of a mineral deposit is a block model including the data on lithology, strength properties and geomechanical characteristics of rock mass. The source information of modeling is the rock mass structure and lithology characteristics, the core description and lab-scale testing of rock samples. At the stage of the source data analysis, it is important to interpret the input data correctly toward the proper rock mass quality rating, to delineate geomechanical domains within a mine field and to determine the weighted values of rock mass properties within the limits of the domains. The proposed joint alteration number algorithm and dendrogram of correlation between the Barton and Bieniawski systems of rock mass classification allow the correct and unambiguous interpretation of the core analysis data for the assessment of the basic properties of rock mass. The method of the weighted categories in delineation of geomechanical domains enables composing core sampling intervals into larger intervals, which makes it possible to delineate large and solid and geomechanically consistent areas in rock mass while preserving the statistical distribution of geomechanical characteristics within the limits of the delineated domains for the purposes of the probabilistic and variographic analysis. The nonlinear weighted evaluation procedure for the equivalent values of a rating allows finding the most representative value in a geomechanical domain and provides a reliable specifics of the stability characteristic of rock mass.
The authors wish to appreciate participation of the members of the Center for Geodynamic Safety, NorNickel’s Polar Division in these studies, namely, V. P. Marusyuk, Director, M. P. Sergunin, Head of a department, and Leading Specialists A. A. Bazin and A. K. Ustinov.

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