Research On The Safe And Efficient Blasting Technology Of Hard Rock Roadway With Large Section In Deep Coal Mine

With the coal face replacement are more and more hard, the new level of some main mines in Huainan mining has exceeded-1000m. Deeper levels means the greater pressure, and also means that the geological condition of the rock surrounding roadway is more complex. Production efficiency of shallow hole blasting which is generally used in the coal roadway driving is not only low, but also has a lot of safety hidden trouble, in the promotion of "cost reduction" this blasting method is gradually being replaced; Deep hole blasting both here and abroad has been a success, and the deep hole blasting with the use of drilling rig can greatly develop the tunneling efficiency, so the deep hole blasting technique is the development direction of mine rock roadway heading in the future.In this paper, with the theory of rock fracture mechanics and detonation dynamics as the foundation, analysis and calculate the theoretical radius of crack area and crush area in rock blasting process; using of blasting funnel experiment which controls of gun perforation depth and charge, and using numerical simulation technology, analysis the cutting method under the test conditions; finally combining with the examples in Huainan mining area, obtained the optimal cutting method and tunneling technology can be used in underground hard rock tunnel excavation.Through theoretical analysis, laboratory tests and field tests, the following results are obtained.:1)The actual construction, the depth of the hole more than in the2.1-2.3m and statistics the average2.25m, shothole utilization rate are above85%, most in more than90%, high reached91.3%, the average hole utilization rate of90.4%. In the sandstone driving, the rock quality is good, the quality of tunnel is good, and the amount of excavation is basically controlled within the100mm, without the digging..2)Working face of rock fragmentation fully, small bulk rate, to pour coal and rock loading and effectively protect the roadway excavation equipment and utensils from collapse stone impact damage.