To study the process and mechanism of rock tensile failure

the advantage of weighted inversion method in solving moment tensor of Brazilian splitting test is first verified by simulation calculation. Acoustic emission monitoring

event location and moment tensor inversion are performed during the Brazilian splitting test on granite

and the difference of moment tensor results between standard inversion method and weighted inversion method is analyzed. Then the moment tensors inverted by the weighted inversion method are analyzed by the K-means clustering algorithm. The results show that the weighted inversion method can reduce the moment tensor inversion error of Brazilian splitting test. In the laboratory granite Brazilian splitting test

the weighted inversion method greatly optimizes the distribution of the double couple component and pressure/tension axis of the acoustic emission event

which makes the inversion result more reasonable. For the weighted inversion result

the events selected for moment tensor inversion can be divided into three clusters

and the source type

stress state

focal mechanism

radiation pattern of events in the same cluster are similar. There is no significant difference in the occurrence time and position of events in different clusters

but in the later stage of the test

events with obvious tension characteristics in the east-west direction increase sharply and gather near the center of the disc and then dominate the whole rupture

which eventually leads to the split of the specimen. The results reasonably explain the failure process and mechanism of the Brazilian splitting test on granite

and can provide further guidance for the study of rock mechanical behavior.