特厚煤层综放开采工作面合理采放比数值模拟研究

Numerical Simulation Research on Reasonable Caving Ratio of Extremely Thick Coal Seam with Fully Mechanized Caving Mining

采放比作为综放开采工作面重要参数,对顶煤的破碎影响程度较大,直接影响到工作面高效回采。鉴于此,以塔山矿二盘区3_(-5)^(#)煤层8209工作面地质条件为背景,对煤壁前方支承压力与顶煤破坏情况之间的关系进行分析,结合顶煤破坏机理和现场实际,采用数值模拟方法对不同采放比下顶煤的支承压力分布情况、破坏范围以及工作面煤壁的稳定状态进行分析研究,进而确定塔山矿8209工作面合理的机采高度为3.5 m,采放比为1∶2.22。

As an important parameter of fully mechanized caving face,the caving ratio will directly affect the top coal recovery rate.Based on the geological conditions of No.3_(-5)coal seam 8209 working facein the second panel of Tashan coal mine,analyzes the relationship between the supporting pressure in front of the coal wall and the destruction of the top coal.Combined with the failure mechanism of the top coal,the stress distribution of the top coal,the broken state and the stable state of the coal wall under different mining and drawing ratios are analyzed and studiedunder the comparison situation.It is determined that the reasonable mechanical mining height of the 8209 working face of Tashan mine is3.5 m,and the mining and caving ratio is 1∶2.22.