Application of mass fracturing analysis to assess Irokinda gold deposit rock mass stability

The main structural features of a rock mass that determine its mechanical and deformational properties and, consequently, its stability are fracturing, blockiness, and layering, as well as the rock composition itself. A large number of small open cracks on the walls of workings also appear during blasting and mechanized excavation, which underestimates the main structural parameters of the massif and deteriorates the stability forecast according to the Z.T. Bieniawski system, which is frequently used in practice. The purpose of the engineering-geological study of mass fracturing of the deep horizons of the Irokinda gold deposit was: qualitative assessment of the rock mass properties, approximate quantitative assessment of the rock mass properties by calculation, and identification of hazardous intervals within the entire rock mass. The availability of refined data on rock mass fracturing allows for both upward and downward adjustments to the stability class, including those during mine development. It also identifies promising areas for studying crack propagation patterns during blasting operations and their impact on the integrity of the peripheral rock mass, as well as blast control to reduce the impacts on the rock mass. The obtained results of the qualitative and quantitative fracturing study were interpreted in terms of their genetic origin to interpolate the estimates of fracturing parameters and rock property indicators in the massif and the possibility of taking them into account when calculating the stability of mine workings using various methods. Based on the obtained documentation materials of the mine walls and the study of borehole cores, a 3D model of individual sections of the Irokinda gold deposit was created. It allows to improve the accuracy of rock mass zoning for addressing current production challenges, such as predicting geomechanical processes and improving their management methods.

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