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

• Published in: Advances in materials science and engineering Vol. 2017; no. 2017; pp. 1 - 8
• Main Authors: Lin, Guan, Chen, Lianjun, Wang, Xiao, Wen, Zhijie, Zhang, Hualei
• Format: Journal Article
• Language: English
• Published: Cairo, Egypt Hindawi Publishing Corporation 01.01.2017; Hindawi; Hindawi Limited; Wiley
• Subjects: Acoustic emission; Acoustics; Atoms & subatomic particles; Coal mining; Compressive strength; Damage; Disasters; Discrete element method; Evolution; Failure; Field study; Laboratories; Mechanical properties; Science; Simulation; Size effects; Stone; Strain
• ISSN: 1687-8434; 1687-8442
• DOI: 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.