Vasyl'yev V. Substantion of boundary parameters of concentrating mining operations under developing adjacent coal seams in Western Donbass

On the basis of the method of boundary elements and the model of linear hereditary environment using P.P. Balandin's criterion calculating algorythm of determining stress and strain condition of stratified inhomogeneous rock massif concerning simultaneous extraction of two adjacent coal seams under advanced overworking has been developed. The results of calculation concerning developed algorythm are generalized and represented as relationship characterizing regularities of rock pressure under extraction of adjacent seams in considered mining and geological conditions, that is: "the character of maximum closeness of floor and roof of extracted coal seam in conditions of overworking in dependence on module of elasticity of enclosing rock and distance between stoping faces on adjacent seams has been established; "quantitative estimation of degree of influence of seam space thickness and distance between stoping faces of adjacent seams on vertical roof displacement of coal seam under conditions of overworking has been carried out; "correlative relationship for maximum roof displacement of top and botton seams has been obtained. The relationships take into account modules of elasticity of enclosing rock and coal, depth of development, seam and seam space thickness and the distance between stoping faces on adjacent seams. Mine investigations of parameters of rock pressure in stoping and development workings in the process of overworking adjacent coal seams have been carried out. The difference between results of calculation and real values of investigated parameters is not more than 20%. The real economic effect due to cost reduction of support and repeated using of 115th side drift of 117th "bis" of longwall face when it is located on the distance of 25 m from edge part of seam c61 in 808860 hrn.