COMPUTER SIMULATION OF THE INITIAL STRESS FIELD FOR ROCK BURST PREDICTION

Abstract

The article discusses the features of rock burst prediction based on the use of computer simulation. The model represents the Vorkuta deposit, the development of which is complicated by mining and geological conditions and the influence of tectonics, which create prerequisites for the formation of an initial stress field. An analysis was made of how the stressstrain state of the massif affects the manifestation of rock bursts, based on which we propose a method for predicting them, including the model of a hardening massif. The coal layer in this case is a plastic material. Transitional yield zones are formed directly in the
coal seam, which change their state over time and play a role in creating yield strength maxima, making an additional contribution to the redistribution of stresses, as well as hardening zones, expressed through higher-order polynomials when describing the stress state. The calculation model includes several combinations of the deformation modulus and
Poisson's ratio in the range of 0.8Emean...1.2Emean and 0.8νmean...1.2νmean, where Emean and νmean are average
values determined by laboratory methods. The calculated values obtained are expressed in principal stresses. For values at the points of rock bumps (according to mining plans) and at the indicated neutral points, where rock bumps were not observed, the density of the number of realization of stress values was calculated. For each of these cases, the distribution of probability densities has a different character. At the points corresponding to rock bumps, there are prerequisites for a sharp change in the stress state during the formation of the outcrop surface, while at other points there are prerequisites for a gradual decrease
in tension. This model allows us to establish causal relationships. The resulting solution does not contradict the practice of mining operations and can be reflected in the regional forecast.