深孔预裂爆破在坚硬顶板工作面中的应用

Application of Deep Hole Pre-splitting Blasting in Hard Roof Working Face

基于某矿8935试验综放工作面的坚硬顶板条件,对比分析实施顶板预裂爆破后顶板变化情况及来压特征的变化情况。经分析可知:8935工作面直接顶的初次垮落步距平均22.0 m,基本顶的初次来压步距为46.5 m,基本顶初次来压期间的矿压显现非常明显;实施了深孔预裂爆破措施后,直接顶初次垮落步距减小至13.2 m,基本顶初次来压步距降低为34.5 m,基本顶的矿压显现非常不明显,初次来压期间煤壁平整,顶煤碎裂掉落,也没有出现移架困难与支架不接顶等问题。

Targeted on the hard roof condition in 8935 working face with fully mechanized top caving coal in a coal mine,the change of roof and pressure characteristics after roof pre-splitting blasting is analyzed and compared. It is found that the initial collapse space of roof in the working face is 22. 0 m,and the initial base roof pressure space is46. 5 m,the strata pressure behaviors during the initial pressure is very obvious. The implementation of the pre-splitting blasting made the initial collapse space reduced to 13. 2 m,and the initial base roof pressure space reduced to34. 5 m,no obvious the strata pressure behaviors being seen,and the coal seam rib sides keep the normal state. Although some roof coal drop down,no problems related to supports such as difficulty to move and hard to reach the roof being emerged.