Experimental Study on the Characteristics of Acoustic Emission Source of Rock under Uniaxial Compression

Abstract

One of the main research problems in acoustic emission (AE) monitoring technology is to identify the source of the acoustic emission. Processing the acoustic emission signal is the only way to solve this problem, and then to achieve the purpose of identifying the material destruction mode. Using acoustic emission monitoring technology, the acoustic emission of granite under uniaxial compression was monitored and analyzed, and the coupling characteristics between the acoustic emission signal parameters of granite under different loading rates were obtained. The results show that during the process of rock shear failure, the peak intensity of the rock, the peak value of the absolute energy of acoustic emission, the cumulative amount of acoustic emission and the loading rate showed a positive correlation. The correlation diagram of the AE ringing count and the duration shows a triangular distribution, and as the rock loading rate decreases, the angle of the triangle top angle of the correlation diagram increases. The distribution relationship between the absolute energy of AE and the duration can be fitted using a unary quadratic function, and as the loading rate decreases, the opening of the fitting curve gradually increases, and the width of the correlation graph gradually decreases. The correlation graph of absolute energy and amplitude of AE is linearly distributed, and as the loading rate decreases, the slope of the fitted line of absolute energy and amplitude of AE gradually decreases, and the width of the linear channel of the correlation graph decreases. It is found that there is a good regularity between the correlation graphs of different parameters of the acoustic emission of the rock during the uniaxial compression failure process, which is an effective method to identify the characteristics of the source of the acoustic emission. Therefore, establishing the correspondence between the characteristics of the AE source and the loading conditions will promote the development of acoustic emission technology in the monitoring of the stability of the surrounding rock of underground projects.