Impact Failure of Flattened Brazilian Disc with Cracks—Process and Mechanism

Abstract

Split Hopkinson pressure bar (SHPB) has been used to study the dynamic failure pattern of flattened mortar Brazilian disc under impact load. Each disc contains several prefabricated cracks paralleled to each other. Dynamic FEM has also been adopted to simulate such failure behavior. The mechanism of crack initiation, propagation and cut-through have been scrutinized with both experimental and numerical approaches. Influence of the number of the prefabricated cracks on the specimen strength and acoustic emission (AE) performance can be observed and studied. The results show that the strength decreases and AE counts increases, when the number of the prefabricated cracks increases.

Keywords

paralleled cracks / flattened brazilian disc / impact load / SHPB / failure process / acoustic emission

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