METHODS FOR DETERMINING THE INITIAL STRESSES OF THE ROCK MASSIF BY IN-SITU MEASUREMENTS

Abstract

Emerged in our country in the early 40's of the last century, first in coal mines, and then in the 70's also in metal mines, the problem of rock bumps or dynamic phenomena remains to this day not finally solved. So, on the Tashtagolsky mine the number of dynamic phenomena reaches up to 1.5 thousand a year, on Sheregeshsky mine, there were more than 70 dynamic phenomena with energy up to 107 J between 1995 and 2005, on Kazsky mine were marked more than 200 phenomena from 1987 to 2007.
At mines of the Urals, for example, at SUBR, the number of rock bumps reaches 3000 per year, sometimes with fatal consequence, and at the iron ore mines of the Urals, in connection with deepening of mining works, their number also increases. Suffice it to say, that during the period from 1990 to 2009 there were 30 rock bumps and 10 technogenic earthquakes at just one Estyuninskaya mine.
The cause of these phenomena lies in insufficient geomechanical substantiation of parameters of preventive measures and, first of all, in absence of calculated forecast of shock hazard, which allows to prevent dynamic phenomena at the stage of designing mining works and construction.
Thus, the calculated geomechanical forecast and determination of the initial stress state at the mines remain very relevant to date.