Study on the Acoustic Emission Characteristics and Fracture of Coal Samples with Different Bedding under Brazilian Splitting Test

• Published in: 2024 International Conference on Energy and Electrical Engineering (EEE) pp. 1 - 8
• Main Authors: Zhou, Peiming, Fu, Yinlan, Liu, Xudong, Zhao, Fuping, Liu, Wei, Zhang, Xiong
• Format: Conference Proceeding
• Language: English
• Published: IEEE 05.07.2024
• Subjects: Acoustic emission; Anisotropic magnetoresistance; bedding angle; Brazilian splitting; Coal; Electrical engineering; Hydraulic systems; Loading; Monitoring; Real-time systems; shear failure; Surface cracks; Tensile failure
• DOI: 10.1109/EEE59956.2024.10709751

To investigate the crack and acoustic emission characteristics of coal sample with diverse bedding angles under Brazilian fracturing test, the Brazilian fracturing tests with diverse bedding angles of 0°, 30°, 45° and 60° were conducted, and the evolution regular pattern of acoustic emission signals were monitored in real time, and then the fracture features of coal sample with diverse bedding angles were contrasted and studied. The experimental results indicated that the maximum peak load is 2.07 kN when the bedding angle is 0°, and the minimum peak load is 0.51 kN when the bedding angle is 45°. The tensile strength of coal samples varied a U-shaped tendency with increasing bedding angle. During the initial phase of loading, the acoustic emission count is very small, but it increases to some extent in the middle stage of loading. By the late stage of loading, the damage level of the coal samples with bedding angles of 0° and 45° is the greatest, and the acoustic emission count exceeds 6,000 times. Combined with the analysis of acoustic emission RA-AF characteristics, it is shown that the failure of coal sample with diverse angles of bedding is not a single failure, but a complex failure of tension and shear, in which tensile failure is the primary failure form. This study provides some guidance for analyzing fracture characteristics in diverse bedding directions and forming complex fracture networks in hydraulic fracturing.