6.0 m大采高厚硬顶板工作面强矿压特征

Characteristics of strong mining pressure in 6.0 m high mining height and thick hard roof working face

针对大采高工作面覆岩顶板运移规律及工作面矿压显现强烈的问题,通过理论推导、UDEC数值模拟与现场调研的方法,分析了小保当煤矿6.0 m大采高厚硬顶板工作面推进过程中煤层顶板覆岩破断形式、垂直应力分布特征及变化规律。研究了小保当一号煤矿112207工作面顶板覆岩压力的分布规律,并通过数值模拟分析得出综采工作面煤壁支撑影响区、顶板离层区、后方压实区的范围。研究结果表明:随着工作面的不断推进,厚硬顶板形成“砌体梁”结构,形成覆岩“F”型悬顶,对煤壁前方产生高应力、大范围的超前支承压力区,通过理论计算结合数值模拟,并综合现场实际观测结果得到:工作面煤壁支撑影响区为工作面前方约70 m内;顶板离层区为工作面后方约50 m内;后方压实区为工作面后方50 m之后;对厚硬顶板综采工作面进行矿压显现分析,研究结果可为矿山安全高效生产提供重要参考。

A case study was performed in Xiaobaodang Coal Mine to evaluate the movement of the overlying rock and mining pressure under the condition of large mining height.Theoretical derivation,UDEC numerical simulation and on-site investigation were carried out at a 6.0 m mining height with thick hard roof working face to study the fracture pattern,the vertical stress distribution characteristics and change law of the overlying rock of the coal roof.The distribution law of the roof overburden pressure in the 112207 working face of Xiaobaodang No.1 Coal Mine was studied,and the range of the influence zone of the coal wall support,the roof separation zone and the rear compaction zone of the fully mechanized mining face was analyzed through numerical simulation.The research results show that with the continuous advancement of the working face,the thick and hard roof forms a"masonry beam"structure,leading to an overlying rock"F"-shaped suspended roof,which generates high stress and a large-scale advanced supporting pressure zone in front of the coal face.The coal face support area of the working face is from the coal face to the front about 70 m.The roof separation area is about 50 m behind the coal face.The rear compaction area is from the coal face to 50 m into the goaf.The analysis of the mining pressure appearance of the thick and hard roof fully mechanized mining face is of great significance to the safe and effective production of the mine.