机采高度对顶煤冒放性与煤壁片帮的影响

摘要

According to the problems of collapse of top-coal and coal wall spalling in fully-mechanized caving mining with large mining height,the influence of coal cutting height to coal recovery coefficient and rib spalling was studied by theoretical analysis,numerical simulation,technical and economic comprehensive comparison and analysis.Through establishing the rib spalling compression-shear mechanical model of fully-mechanized caving mining face with large mining height,the rib spalling mechanism was analyzed,and the reasons that fully -mechanized caving mining face with large mining height more easily coming up rib spalling than large mining height fully-mechanized face in the same cutting height were studied.Increasing the active support reaction from hydraulic support to the top-coal and selecting the reasonable hydraulic support structure can enhance the top-coal caving and reduce rib spalling probability at the same time.Comprehensive analyzing the influence of difference coal cutting height to coal recovery rate,rib spalling control,engineering and equipment investment,the biggest coal cutting height was confirmed by 4.5 m in fully-mechanized caving mining face with large mining height of Guanzigou Mine.The two column cover type caving hydraulic support of ZFY12000/26/47 worked well in Guanzigou Mine.%针对特厚煤层大采高综放开采顶煤冒放性与煤壁片帮难题,采用理论分析、数值模拟及技术经济综合对比分析等方法,分析了工作面机采高度对煤炭资源回采率及煤壁片帮的影响.通过建立特厚煤层大采高综放工作面煤壁片帮的压剪力学模型,分析了大采高综放工作面煤壁片帮机理,研究了相同机采高度情况下大采高综放工作面较大采高综采工作面煤壁片帮更加剧烈的原因.增加液压支架对顶煤的主动支护作用力及选择合理的液压支架架型结构参数,既可以提高顶煤的冒放性,同时还可以降低煤壁的片帮概率.综合分析不同机采高度对煤炭资源回采率、煤壁片帮控制及工程与设备投资的影响,确定罐子沟煤矿大采高综放工作面机采高度为4.5 m,设计研发的ZFY12000/26/47型两柱掩护式整体顶梁大采高综放液压支架使用效果较好.