| Thick coal seam in existing reserve accounts for more than45%of the total reserves of coal. Due to it has high recovery rate, easy to operate, large ventilation section area, less coal dust, balanced gas emission etc. advantages, fully-mechanized high cutting longwall coal mining has becomed one of methods of thick coal seam mining. But, it is mostly used in hard coal seam and good roof conditions, less used in mining area of complex geologic conditions.The size3coal seam in Zhaozhuang Coal Mine of Jincheng Anthracite Mining Group has coal quality loose and soft, joint fissure develop, varied geological structure features, when use fully-mechanized high cutting longwall coal mining, coal wall spalls serious (The max depth of coal slide for up to1880mm, the max vertical height for up to2900mm), that seriously influence the safety mining works. At present, high cutting longwall coal mining technology still can’t effectively guide safe and high effective mining under complex geological conditions of the soft and thick coal seam similar to ZhaoZhuang Coal Mine.This text regards the coal face1306in Zhaozhuang Coal Mine as the research object, adopts theoretic analysis, numerical simulation and underground measured combine method, studies the regularity of strata behavior for soft coal seam, the structure and movement laws of overlying strata for, coal wall spalling, and spalling control technology during construction, and has obtained the following research reasults:(1) With theoretic analysis, studies the structural form and movement destruction rules of overlying strata of full mechanized longwall coal mining face under complex geologic conditions.(2) By field measurement and analysis, further revealed the basic feature and regularity of strata behavior of under complex geologic conditions soft coal seam full mechanized longwall coal mining face.(3) Ascertain the main influence factors of wall coal spalling of under complex geologic conditions high longwall coal mining face, adopts accident tree analysis method to analyze the danger of spalling, and put forward effective preventive measures.(4) During construction of soft coal seam high longwall coal mining face, the study of use superfine cement based grouting material to prevent coal wall spalling.These research result not only effective guide the coal face1306safe and high effective mining, but also expand application scope of high cutting longwall coal mining, and provide valuable experiences and beneficial engineering practice demonstration, all those have important practical meaning. |
