Abstract:In cut blasting, the presence of empty hole has important significance. Through the theoretical analysis of the mechanism, it is concluded that the empty hole has three main functions:first, it can cause the explosion stress concentration, lead to the orientation of blasting crack development; second, the empty hole adds a free surface to other charging cutting holes, strengthens the hole wall stress wave reflection effect, enhances groove cavity rock crushing, and provides the guidance for the broken rock and expansion mobile space;third, the shearing action between empty hole and the charging cutting hole further strengthen the rock damage.

Abstract:According to the technical problems in the development of production technology of emulsion explosive, from the technical economic, safe and reliable point, the typical technology characteristics were analyzed and the guiding ideology of the technical progress was summarized, then the viewpoint adapted to the development of the industry was also put forward.

Abstract:Choosing appropriate parameters and model, the simulation study in loose blasting stress field of the rock blast hole affected by in-situ stress was made using ANSYS/LS-DYNA numerical analysis software. The results show that the explosion distribution around the hole, rock displacement and the bursting of the particle rock will be changed by the influence of in-situ stress, the strength of the stress field is restricted, the movement speed of the particle decays faster, and the development length of crack decreases.