Pre-split blasting method is commonly adopted in coal seam roof weakening to improve the initial mining coal recovery rate, Changcun Mine 2206 working face was taken as background, based on the engineering geological conditions, the original drug structure and pre-split blasting principle analysis, a new shaped tube of drug structure was put forward, simulated by two kinds of charge structure crack effect ANSYS/LS-DYNA numerical, the results showed that the binding energy tube charge structure can realize the directional fracture blasting, can improve blasting effect and reduce the amount of explosive.