Size Effect on Acoustic Emission Characteristics of Coal-Rock Damage Evolution

• Main Authors: Zhijie Wen, Xiao Wang, Lianjun Chen, Guan Lin, Hualei Zhang
• Format: Article
• Language: English
• Published: Hindawi Limited 2017-01-01
• Series: Advances in Materials Science and Engineering
• Online Access: http://dx.doi.org/10.1155/2017/3472485

Coal-gas outburst, rock burst, and other mine dynamic disasters are closely related to the instability and failure of coal-rock. Coal-rock is the assemblies of mineral particles of varying sizes and shapes bonded together by cementing materials. The damage and rupture process of coal-rock is accompanied by acoustic emission (AE), which can be used as an effective means to monitor and predict the instability of coal-rock body. In this manuscript, considering the size effect of coal-rock, the influence of different height to diameter ratio on the acoustic emission characteristics of coal-rock damage evolution was discussed by microparticle flow PFC2D software platform. The results show that coal-rock size influences the uniaxial compressive strength, peak strain, and elastic modulus of itself; the size effect has little effect on the acoustic emission law of coal-rock damage and the effects of the size of coal-rock samples on acoustic emission characteristics are mainly reflected in three aspects: the triggering time of acoustic emission, the strain range of strong acoustic emission, and the intensity of acoustic emission; the damage evolution of coal-rock specimen can be divided into 4 stages: initial damage, stable development, accelerated development, and damage.