Abstract:Impact experiments in sandstone were carried out with the split Hopkinson pressure bar(SHPB) apparatus. The impact process and energy dissipation were analyzed. The influence of the porosity of the rock on energy dissipation was also investigated. The stress-strain curves in sandstone of different impact velocities were obtained by the one-dimensional stress wave theory. Those curves lay foundation for numerical simulation of rock fracture under impact loading and provide help for selecting suitable model and parameters of sandstone. The damage profiles of sandstone specimen under the impact loading show that the sandstone exhibits obvious shear damage under the impact loading because sandstone is a typical porous medium containing large quantities of defects such as pores,cracks and grain boundaries at the microscale. The experimental results also indicate that rock porosity plays an important role in the energy dissipation process and the energy dissipation increases with the porosity increase of man-made rock.