Abstract: Aiming at the technical problems in deep hole blasting technology,and the high explosive power at the moment of explosion,but the limited range of fracturing and insufficient rock breaking energy,a deep hole explosive fracturing technology of liquid explosive was proposed.Based on the superior fluidity of liquid explosive and its small critical initiation diameter,and the components of water glue explosive of third safety level in coal mine,a water glue liquid explosive formulation for coal mine was developed,which has stable performance,low sensitivity and fluid physical form,solves the problem of large angle and deep hole charging,and provides condition for single hole repeated blasting,through removing the gelling agent and crosslinking agent from the components of water glue explosive,and changing the proportion of the methylamine nitrate,ammonium nitrate and sodium nitrate etc.Research shows that the crystallization temperature of liquid explosive is controlled at 15.0-16.9 ℃,which is suitable for the temperature environment of coal mine.The sodium nitrite chemical foaming method is adopted to adjust the density of liquid explosive to 1.2 g/cm3.The average detonation velocity of the liquid explosive is 3 852 m/s,and the explosive mechanical properties obtained based on these data have reached the coal mine safety explosive standard.Taking the deep hole blasting test of the No.408 track roadway in Yungang Coal Mine of Datong Coal Mine Group as the background,the liquid explosive has stable performance,and can be detonated normally with detonating cord.Through deep hole blasting test on hard roof,the explosive power of liquid explosive,water glue explosive,and emulsion explosive are basically the same,and the liquid explosive meets the performance requirements of coal mine safety.The use of liquid explosive in conjunction with jet blast tube can truly couple the liquid explosive with tube,which makes the explosion shock wave accurately collide in the predetermined cutting direction,enhances the explosive energy utilization rate in fracture direction,and achieves the effect of largespacing deep hole directional blasting of hard roof.