Abstract: The formation and propagation mechanism of directional fracture blasting crack of the slit tube were analyzed.The initial cracks were formed under stress concentration and pressure difference at cut joints.Then the crack propagation process experienced the growth stage under the action of the tangential tensile stress，steady crack propagation phase and macroscopic crack propagation caused by detonation gas driving pressure.On the basis of theoretical analysis and engineering practice，the directional fracture blasting technology of joint-cutting cartridge in composite wedge cut holes and peripheral holes were proposed.The spot application indicated that the cut tube blasting can improve the utilization rate and hole mark rate of blast holes，reduce the blasting disturbance damage to surrounding rock and improve the effect of cut blasting and perimeter blasting.In brief，it is conducive to quicken speed of roadway drivage.

Key words: Rock roadway, The full section of middle-depth hole, Cut tube, Directional fracture blasting