Abstract: Split Hopkinson Pressure Bar (SHPB) experiment is one of the important means to study the compressive properties of materials under medium and high strain rates. In this paper, ABAQUS simulation was used to study the size effect of carbon fiber reinforced resin matrix composites in Hopkinson pressure bar experiment. The effects of different impact velocities, impact directions and sample sizes on the stress of the samples were investigated. The results show that when the sample is impacted along the fiber direction, the stress of the sample is not affected by the length of the compression direction, but is greatly affected by the impact velocity, and the smaller the sample size is, the more obvious the effect is. When the specimen is impacted perpendicular to the fiber direction, both the compression direction length and the impact velocity have great influence on the stress of the specimen. The stress of the specimen increases with the decrease of the specimen size and the increase of the impact velocity.

Key words: carbon fiber reinforced composite materials, separated hopkinson pressure bar, ABAQUS simulation, size effect