The sudden throws of rock, coal and gas in the mines

                           The sudden throws of rock, coal and gas in the mines                      

• - the natural manifestation of the active shock waves of stretching

     The exploitation of minerals is the vital necessity for any civilized complicities. It never ceased, in spite of the complicated and often tragic circumstances. It maybe, the most serious from those are the difficult predictable in a perspective and sudden in each privat case throws of rock, coal and gas in the mines: besides of material wastes, for those it had to pay by great enough blood. By empirical - on the base of numerous observations during of two last centuries - it was worked the methods for weakening of this phenomenon (sometimes even its prevention), or even though done in good time its prophecy; often the such semiempirical finds was found successful. Nevertheless, well-founded and thinked struggle with this threatening phenomenon require of elucidation of its natural essence and detailed mechanism of its rise.

                                                         The attentive analysis testifys: the throw of rock (and gas) is the direct result of action in the vicinity of mine coal-face of the active shock wave of stretching, which is initiated by the technological process of mining (and sometimes by natural causes). Behind of shock front of this wave, in direction, opposite to its motion, the rock (together with its filler) is thrown aside with a velocity exceeding the velocity of stress wave in the deformed (as a rule, broken) material: this torrent of the gas - rock mixture represent the material essentiality of the phenimenon of throw. Therefore, for to loosen a throw phenomenons and to exclude the possibility of its rise it is necessary to create such conditions at which the appearance and development of the active shock waves of stretching is difficult or excluded; of course, the such actions must no prevent the process of mining.

     The clearly formulated notion about of the active shock waves of stretching and principled its ground had been introduced in mechanics in the monograph: L.G.Philippenko, "Strong Shock Waves in the Continuous Bodies", which had been published on Russian at 1992 year (Kiev, Ukraine). Detailed investigation of the properties of such waves and theirs role in formation of sudden throws of rock, coal and gas in the mines had been carried  uot by author at 2006 - 2008 years and had been included in the text of monograph in the process of its supplementing and completing. On this base there had been indicated the recommendations for struggle with this phenomenon in the industrial conditions.