FORECASTING METHOD OF ROOF BREAKS AND CAVING FORMATIONS WITHIN SECTION OF PRELIMINARY MINE WORKING, WHICH IS NOT FIXED WITH SUPPORT (VERSIONS) Russian patent published in 2015 - IPC E21C39/00 

FIELD: mining.

SUBSTANCE: invention proposes two versions of a method - for a bottom-hole zone and a section remote from the bottom-hole zone. In both versions, measurements of amplitudes of pulses of electromagnetic interference signals (EMI) are made. Before EMI signals are recorded, a gauging station is formed to make measurements of values of amplitudes of EMI signal pulses, for which there used is a lead ball with a fastener at the height of 1.5 m, which is fixed in its roof rock, from soil of the working, thus arranging them along the vertical axis of this plane; after that, the specified device is arranged in front of the above fastener. Values of amplitudes of EMI signal pulses are measured; maximum values are chosen - N_max (Version 1) and N'_max (Version 2), which are compared to critical value N_cr of amplitude of EMI pulses along well horizon. If N_max>N_cr or N'_max≤N_cr, then, distance of the considered section is assessed as dangerous. Scaling of low-browed roof breaks and lumps of rock is performed with a tool. Operations are performed until N_max≤N_cr or N'_max≤N_cr is obtained.

EFFECT: improving accuracy of measurements by means of a single order of selection of measurement points, fixation of the number of counts and regular orientation of the chosen device.

6 cl, 2 dwg