Mechanism And Application Of Directional Fracture Blasting With Slotted Cartridge

The mechanism of directional fracture blasting with slotted cartridge and its application in slope presplitting blasting had been studied by theoretical analysis, numerical calculation, model test and field test. First, the three main factors of the impact on blasting effect were carried out numerical and experimental study, namely, non-radial coupling coefficient a, kerf width W and the slotted pipe material f.The result showed that adopting the pore diameter of 42mm, non-radial coupling coefficient of 1.62, kerf width of 6mm and rigid PVC pipe material, the binding energy effect was significant and model test and numerical results were agreed. Secondly, slotted cartridge with axial segment charge had been simulated and experimented. The research indicated that when non-axial coupling coefficientβvalue was at 33.3%-50%, the directional fracture blasting effect was remarkable. Finally, the simulation study of slotted cartridge double blasthole was carried out with pore diameter of 90mm and 250mm. And 90mm diameter blastholes were used in presplitting blasting slope field tests. The research conclusion can be shown that directional fracture surface was smooth, the rates of half-hole marks were higher and apparent slope forming quality had been significantly enhanced.