RESEARCH OF ROCK BUMP HAZARD ON UNDERGROUND MINES OF THE FAR EAST AND TRANSBAIKALIA

Abstract

Features of rock burst hazard on underground mines of the Far East and Transbaikalia are considered. All range of dynamic manifestations of rock pressure and technogenic seismicity is being registered there. It is established that nonequal component fields of tension of compression are present in rock massifs. The greatest ones are focused in the direction from northeast to southeast. These fields of tension exceed a gravitational component from the weight of the rock mass by 1.5-3 times. Excess of the horizontal compressive tension over the vertical ones is defined by their geodynamic position within tectonic active Amur plate. The main approaches are specified to the solution of this problem of the forecasting and preventing of rock bumps, which provide geodynamic division into districts with application of geological structural methods and methods of satellite geodesy, numerical modeling of the stress-strain state conditions (SSS) and control tools of burst hazard of the massif at the regional and local levels. On the example of vein type deposits the possibility of assessment of the SSS of the rock massif at various stages of ore bodies development and substantiation of effective preventive actions is shown. The basic principles of developing of complex geomechanical monitoring system are given and results of application of instrumental methods and technical means of control of burst hazard in the Far East mines. The system of monitoring unites multichannel seismic-and-acoustic and microseismic measuring complexes providing registration of seismic-and-acoustic events with energy from 10 to
10⁶J in the frequency range from 10 to 12000 Hz. The system includes deformation stations, including the laser deformographer capable to register crust shifts with an accuracy of 0.1 nanometers in the frequency range from 0 to 1000 Hz. Temporary synchronization of the system giving the possibility to support united time in all measuring units with a divergence of no more than 10 μs is realized in the system. All registered data are integrated into uniform information network. The technique of the forecasting of bump hazard according to geomechanical monitoring based on the determined consistent patterns of manifestation of seismic-and-acoustic activity in the massif of the deposit inclined to rock bumps and bump hazard is considered.