Abstract: In order to improve the positioning accuracy of acoustic emission during the failure process of layered biotite granulite,a positioning method that is suitable for the anisotropic wave velocity of layered biotite granulite is proposed.Firstly,the anisotropy wave velocity model is established based on the wave velocity measurement results;then,the acoustic emission positioning target function is built,and it is conducted optimization calculation by using direct grid search method;finally,the positioning effects of the new method proposed in this paper and traditional positioning method are verified by conducting acoustic emission test of layered biotite granulite under the uniaxial compression condition.The study results show that the positioning error is 4 mm lower than the one of the traditional positioning method with signal wave velocity,and it can provide the technical basis for analyzing the temporal and spatial evolution regularities of the cracks during the failure process of layered biotite granulite.

Key words: Layered biotite granulite, Wave velocity model, Acoustic emission, Positioning algorithm