This study focuses on the impact of charge structure on the distribution of blast pile morphology in a limestone mine. A combination of theoretical analysis, GDEM-BlockDyna numerical simulation, and on-site optimization tests were conducted to investigate the morphological distribution of step blasting and blast reactors. The change in blast pile morphology with different charge structures was analyzed. The results indicate that the looseness and throwing distance of the blast pile initially increase and then decrease with an increase in the upper charge proportion of the interval section. The height of the explosion pile generally decreases but shows an initial decrease followed by an increase when there is a large air interval proportion. Additionally, the slope angle of the blast pile increases with an increase in charge proportion in the upper section of the interval section but decreases when this proportion becomes too large. These findings demonstrate that explosive pile patterns vary according to charge structure. Furthermore, through numerical simulation methods, effective optimization can be achieved for charge structure, leading to improved on-site explosion patterns and economic benefits for mining operations.