Influence of Intersection Angle of Prefabricated Cracks on Impact Failure of Flattened Brazilian Disc

Abstract

Both experimental and numerical approaches were used to study dynamic failure properties and patterns of flattened Brazilian discs, containing two prefabricated cracks intersected at a varying angle. Mechanism of crack initiation, propagation, and cut-through were scrutinized and influences of the intersection angle on specimen strength and acoustic emission performance were also studied. All primary cracks initialize near the middle or the tip points of the upper prefabricated crack, and they continue to develop along the load direction and finally cut through the specimen. The secondary cracks could be observed in directions almost horizontal or parallel to the directions of prefabricated cracks. Furthermore, it is found that stress intensity factor reaches its maximum for specimen with intersection angle of 0 degree.

Keywords

crack / flattened brazilian disc / impact load / SHPB / failure process / acoustic emission

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