Abstract: The design of blasting parameters directly affects the blasting crushing quality and mining cost of open-pit mines. Aiming at the problems of serious blasting energy dissipation, uneven energy distri⁃ bution, high block rate after blasting and uneven block distribution in high-altitude open-pit mines, the op⁃ timization of blasting parameters is studied based on the deep-hole bench blasting project of an open-pit mine in Xinjiang. Initially, the rectangular hole arrangement method was adopted, and the hole row spacing is set to 6.0 m×4.0 m. Based on the blasting energy control theory, the hole arrangement form and parame⁃ ters were optimized, and the plum-shaped staggered hole arrangement was used to adjust the hole row spac⁃ ing to 5.0 m ×4.0 m. Based on WipFrag software, the fragmentation of blasting pile is quantitatively ana⁃ lyzed, and the blasting crushing effect before and after optimization was systematically compared. The test results show that the uniformity of the original blasting scheme is poor, the characteristic particle size D50 is 388.91 mm, the proportion of large blocks with particle size greater than 464 mm is 44.03 %, and the maxi⁃ mum block size can reach 1 302.09 mm. After the optimization of the parameters, the blasting effect is sig⁃ nificantly improved. Under the optimal working conditions, the bulk rate is reduced to 2.84 %, the D50 is re⁃ duced by 192.11 mm on average, the average sphericity of the rock is slightly reduced, the fragmentation is more uniform, and the maximum ore block size is reduced to 604.69 mm. The optimization scheme can ef⁃fectively improve the distribution of blasting energy, improve the efficiency of blasting operation, reduce the workload of secondary crushing, reduce the production cost of subsequent processes such as shovel loading and transportation, and provide engineering reference for the design of blasting parameters in high-altitude open-pit mines.

Key words: blasting parameters, fragmentation analysis, block rate, WipFrag software, open-pit mine