【摘要】 鉴于煤层群开采采动裂隙的发育规律对于顶板控制具有重要影响,以贵州松河煤矿煤层群混合开采生产地质条件为背景,通过相似物理模拟,研究了煤层群混合开采过程中覆岩裂隙的发育规律。研究表明:煤层群采用混合开采顺序时,覆岩裂隙的发育程度受煤层群复合厚度、层间距、开采顺序的影响;煤层群下行开采时,下层煤开采将导致上层煤裂采比增大,煤层群上行开采时,上层煤开采后裂采比相对较小,但会引起邻近下层已开采煤层顶板内裂隙继续发育,使其裂采比增大;裂采比和煤层复合厚度之间呈对数关系,裂隙发展高度和煤层顶板下沉量之间呈三次多项式关系。研究结果可为煤层群混合开采顶板控制设计提供理论依据。更多还原

【Abstract】 In view of the important influence of fracture development regularity on roof control during coal seam group mining, based on the mining and geological conditions of Songhe coal mine in Guizhou province, the development regularities of rock fractures during mixed-mining of coal seam group were studied by using physical simulation test. Studies show that when using mixed-mining in coal seam group,the development degree of overlying rock fractures is influenced by composite thickness of coal seam, layer distance and mining sequence, etc. In descending mining, the mining of lower seam lead to the ratio of fractured zone height to mining height of the upper seam increasing. In ascending mining, the ratio of fractured zone height to mining height is relatively small after the upper coal seam mining,but the roof fractures in adjacent lower seam may be continuously developed, which making the ratio of fractured zone height to mining height increase. In addition, it show a logarithmic relation between the ratio of fractured zone height to mining height and coal seam composite thickness, while the relation between the fractures developing height and roof convergence shows three degree polynomial relation. The results can provide basis for roof control design in mixed-mining of coal seam group.更多还原