Numerical analysis of deep hole multi-stage cut blasting of vertical shaft using a continuum-based discrete element method

Due to the high in situ stress of deep rock mass and restraining effect surrounding rock, hole blasting vertical shaft faces problems low borehole utilization rate poor effect. In this regard, paper proposes a multi-stage cut technology shaft. Preliminary engineering practice shows that such can make better use explosive energy, reduce increase rate. Furthermore, based on continuum-based discrete element method (CDEM), fractal damage, fragmentation, cavity characteristics are studied analyzed. The results show shaft, if length proportion first stage is too small or large, it will lead formation along direction. Characteristic parameters as damage cavity, fracture degree element, interface trend increasing then decreasing increases, has an optimal value. Under conditions parameters, performance linear charge density set by numerical simulation paper, when accounts for 0.42, energy achieve best