大采高综放工作面煤壁弧型滑动失稳机理与控制技术

Instability Mechanism and Control Technology of Coal Wall Curved Slide at Fully Mechanized Caving Face with Large Mining Height

针对同忻煤矿8107大采高综放工作面煤壁严重片帮事故,综合现场调研、煤岩样力学试验、数值模拟及理论分析,建立大采高综放工作面煤壁弧形滑动失稳力学模型。结果表明：大采高中硬煤层片帮主要形式是煤壁上部的弧形滑动片帮,片帮起始破裂点位于煤壁深部顶煤＂冒落拱＂拱脚位置。严格Janbu法煤壁弧形滑动片帮安全系数计算结果表明：8107大采高综放工作面煤壁片帮关键控制指标为护帮阻力Fr,控制区间1 000-2 000kN;弧形滑动轨迹控制参数α,合理值区间30°-60°;煤体力学参数及顶煤冒落拱相关参数。煤壁片帮主要原因是支架护帮千斤顶进液管路严重泄漏导致支架护帮阻力不足,YHX型液压泄漏检测仪通过拾取分析泄漏产生的高频声波和振动信号实现了液压故障检测和准确定位。

Aiming at the serious rib spalling accidents at 8107 large mining height fully mechanized caving face of Tongxin Coal Mine,combining with the field investigation,mechanical tests,numerical simulation and theoretical analysis,the mechanical model of coal wall curved slide instability is established.The research results are as follows： the main form of rib spalling is curved slide instability in soft coal seam with large mining height.Initial rupture point of rib spalling is located at the springing of top coal caving arch; the results solving curved slide safety factor by using strict Janbu procedure show that key parameter of rid control is the resistance protecting rib Frand its range is from 1 000kN to 2 000k N,the control parameter of curved slipde track α and its range is from 30° to 60°.Then,the mechanical parameter of the coal and the associated parameters of caving arch are also relevant parameters; lack of working resistance and the resistance protecting rib,which caused by leak failure of hydraulic system is the main reasons of rib spalling.Detection and precise location of leak failure can be realized by YHX leak detection instrument through collecting and analyzing the high frequency sounds and vibration signal.