Dynamic mechanical response and failure patterns of ore rocks with varying grades

This study investigates the dynamic mechanical response and energy dissipation mechanism of ore rock with different grades from the Baiyun Ebo West Mine under impact loading. Ore rock samples were taken for dynamic mechanical tests using a Split Hopkinson Pressure Bar (SHPB) system at different impact velocities to unveil its effect on the dynamic strength, energy dissipation, and failure patterns of ore rock. Results indicate that: ① the dynamic strength of the ore rock exhibited a pronounced strain-rate effect, showing a linear positive correlation with impact velocity; ② dissipated energy increased with rising impact velocity, and high-grade iron ore exhibited higher dissipated energy than medium-and low-grade iron ore; ③ particle size gradually shifted from concentrated to more dispersed distribution as the impact velocity increased. This study provides fundamental dynamic parameters for blasting excavation of ore rock in the Baiyun Ebo Mine.