Depth gradients, which arise from variations in geostress at different strata, lead to rapid alterations in the internal stress state of rocks during blasting operations. These changes contribute to heterogeneities in rock strength and blast resistance, thereby presenting potential risks to engineering safety. To understand the damage and fracture patterns typically observed in granite blasting activities within underground engineering projects, we created a series of rectangular six-hole models using the advanced finite element software ABAQUS. By utilizing the Coupled Eulerian-Lagrangian (CEL) technique, the model distinguished between Eulerian parts, segmented into domains, and Lagrangian elements; the Eulerian domain was designated as air, while the Lagrangian section was characterized by TNT to mimic the shock wave propagation following detonation. This research scrutinizes the geostress conditions of granite across varying depth gradients, elucidates the extent and severity of granite impairment induced by blasting, and furnishes innovative viewpoints and methodologies for examining rock damage mechanisms in blasting engineering.