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The optimization of a mining sequence not only reduces stress concentration in surrounding rock but also prevents underground debris flows, significantly improving safety. Firstly, the 870–898 m level of the eastern mining area in the Tiaoshuihe phosphate mine was divided into 25 ore blocks, and six different mining sequences were designed for this area. Then, it was calculated that five ore blocks must be processed simultaneously to reach the annual production output. The distances between the five simultaneously mined ore blocks will inevitably affect the efficiency of the equipment for any scheme. So, a collaborative model considering both the area stability and production capacity was established by combining the distance between the centers of the five ore blocks as an index. Differences in stability, deformation, and plastic zone size between the schemes are compared. The calculation results show that a mining scheme with a convex stepped shape produces the best results. These results provide a general method for entropy-based mining sequence optimization and an optimal solution for the Tiaoshuihe phosphate mine.

Ever increasing mine production capacity and mechanized operations enable advanced drilling equipment to be widely adopted in underground mines. In order to achieve satisfactory blasting performance in tunnel advance, there is a critical need to optimize the blasting technique to match the large deep-hole drilling capability. In this study, through theoretical analysis of tunnel blasting, the layout of cutting holes was found to be the key factor controlling the blasting performance. The deep-hole cutting effect was first investigated by analyzing the influence of the free surface of a hollow hole using the fluid-structure interaction modeling method in ANSYS/LS-DYNA. Then the rock dynamic evolution processes of blasting using a double-cavity grooving and a four-cavity grooving were compared and analyzed towards an understanding of the influence of the spacing and layout of cutting holes on the blasting performance. The comparison results show that four empty hole cut layouts yield larger effective free surface than that of the two empty hole cut layouts. This is because larger compensation space for breaking of rock and expansion of gas is more conducive to improving the energy utilization rate of explosives and thus improving the blasting performance and the footage of cyclic blasting. The results indicated that the blasting performance can be improved by reserving reasonable compensation space in the grooving area.