Fracture and Damage of Slit Charge Blasting in the Layered Rock Mass.

Directional fracture blasting technology of the slit charge has broad application prospects in the drilling and blasting construction of the layered rock mass. In this paper, the method of model experiment and numerical simulation is used to preliminarily explore the fracture damage characteristics of slit charge blasting in the layered rock mass. The results show that the blasting effect of the slit charge in the layered rock mass is significantly different from that of the unlayered rock mass, and the pressure relief of the blasting gas at the layer is the main factor affecting the blasting effect. The length of directional cracks in the slit direction is significantly larger than that in other directions, and the directional fracture effect of the slit charge in the layered rock mass can still be played well. However, both the directional crack length and the damage range of rock mass in the slit direction gradually decrease along the detonation direction. In addition, the damage value of a single-layer rock mass also decreases gradually along the detonation direction. In engineering practice, the directional fracture effect of the layered rock mass can be improved by detonating at both ends of the slit charge at the same time. [ABSTRACT FROM AUTHOR]