Aiming at the problem of large thickness,hard texture and difficulty falling down of overlying roof strata in No.2 coal seam of Tonghe Coal Mine,the method of pre-splitting blasting was proposed to cut the roof and protect the roadway.By means of theoretical analysis and numerical simulation,the reasonable pre-splitting blasting depth was determined to be 16.6 m,and the angle between the blasting hole and the horizontal direction was 75 °.The field test was carried out on No.2105 Face.The field monitoring results showed that after the pre-splitting blasting of the roof strata of No.2105 track roadway,the problem of large-area hanging roof of the hard roof of No.2105 Face was effectively solved,and the role of roof cutting and pressure relief was played on No.2106 belt roadway.
关键词
坚硬顶板/预裂爆破/切顶护巷
Key words
hard roof/pre-splitting blasting/roof cutting roadway protection
维普
万方数据