为解决近距离煤层群下层煤综采工作面过上层煤集中煤柱时压架的问题,以大柳塔煤矿活鸡兔井12306综采工作面为研究对象,分析其过上层煤集中煤柱期间的矿山压力规律、支架工作阻力、动载矿压显现特征,据此分析动载矿压显现的原因为工作面悬顶距离过长,周期来压步距较大,导致基本顶大面积垮落与集中煤柱边界覆岩铰接结构失稳的载荷同时作用于工作面支架上,对工作面支架形成了冲击载荷,支架立柱下缩1.2~1.5 m,形成剧烈的动载矿压。据此提出主要采取工作面调斜、调整周期来压、加大支架工作阻力、提高安全阀开启压力、加快推进速度以及采用合理的采高等技术措施,预防了综采工作面压架事故,保证矿井安全生产。%In order to solve the powered support crushed problem when a fully-mechanized coal mining face in a low seam of contiguous seams passing through concentrated coal pillars in above seam,taking No.12306 fully-mechanized coal mining face in Huojitu Mine Shaft of Daliuta Mine as a study object,the paper had an analysis on the mine strata pressure law,powered support working resistance and mine dynamic strata behavior features when the coal mining face passed through the concentrated coal pillars in above seam.According to the analysis,the causes of the dynamic strata behavior would be overlong suspended roof distance of the coal mining face and a large periodic strata weighting step.Thus a large area main roof falling and lost stability of the overburden strata jointing structure in the concentrated coal pillar boundary were affected on the powered supports in the coal mining face,made an impact load on the powered supports in the coal mining face,the legs of the powered support were drawn back with 1.2~1.5 m and serious dynamic mine strata pressure occurred.The technical measures of the tilt control of the coal mining face,adjustment of the periodic strata weighting,enhanced working resistance of the powered support,improved open pressure of the safety valve,speeding advancing rate of the coal mining face rational cutting height were provided to prevent accidents of the powered support in the coal mining face and to ensure the mine safety production.
展开▼
