Experimental Study on the Influence of Corrosion Duration on the Strength and Failure Characteristics of Sandstone

The surrounding rock structure in underground environments is frequently subjected to corrosion from alkaline groundwater and disturbances caused by dynamic loads of mining blasts. To investigate the impact of the corrosion duration on the dynamic behavior of sandstones, a split Hopkinson pressure bar (SHPB) test system was employed to perform dynamic uniaxial compression tests on sandstones with varying corrosion times. X-ray diffraction analysis based on the test results also examined the corrosion mechanisms affecting sandstone. The findings indicate that sandstone’s dynamic peak compressive strength progressively diminishes as corrosion time increases, transitioning from brittle to ductile behavior. Under consistent impact pressure conditions, the energy dissipation rate of sandstone initially rises before gradually declining with an extended corrosion time. Furthermore, the degree of impact fracture and fractal dimension in sandstone directly correlate with the corrosion duration. Combined with the X-ray diffraction (XRD) test results, it is discovered that the longer the corrosion time is, the greater the degree of damage to the internal structure of the sandstone and the smaller the wave impedance. This study provides a scientific basis and key technical support for long-term stability assessment, dynamic support optimization, and corrosion damage monitoring of underground engineering surrounding rock in an alkaline corrosion environment.