To explore the dynamic characteristics of granite under different impact loading conditions

single and repeated impact tests of granite samples were carried out by the split Hopkinson pressure bar respectively. The stress-strain response

strain rate curve

energy dissipation characteristics

and the failure modes of the samples were analyzed. Results show that in the single impact test

the relationship between the dynamic compressive strength and the specific energy presented a logarithmic function. The damage degree of the granite sample aggravated gradually with the increase of the specific energy. With the increase of the incident peak stress

the curve of the strain rate showed a "double-peak" form

and the second peak gradually became larger than the first peak. The rebound phenomenon of the stress-strain curve in the post-peak phase tapered off. In the repeated impact test

when the sample did not fail

the stress-strain curve generally experienced three stages

i.e.

elastic loading

damage evolution

and post-peak rebound. When the sample underwent the last impact

the post-peak shape of the stress-strain curve was related to the failure degree of the sample. In addition

it was found that as the accumulative specific energy increased

the damage degree of the granite samples increased

and the curve of the strain rate gradually transited from "single-peak" to "double-peak".