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运用MTS 815岩石力学试验系统和PCI-2全数字声发射监测系统对具有突出倾向煤体制备的型煤试件单轴压缩和循环加载过程中的AE特征进行了试验研究,利用扫描电镜和数值模拟软件分析了声发射事件的来源.结果表明:单轴压缩过程中,随着煤样变形的增加,AE各参数呈上升趋势,在屈服阶段的后期出现最大振幅和最密集AE事件区,预示试件将发生破坏;AE事件累计曲线和振幅变化曲线与单轴压缩应力应变曲线相似,可在现场用以判定煤体失稳与破坏;随循环载荷作用次数的增加,AE事件及其能量呈现递减趋势;在卸载阶段无AE事件出现.四种微结构变化是煤样产生声发射事件的源.
The MTS 815 rock mechanics test system and the PCI-2 digital sound emission monitoring system were used to study the AE characteristics during the uniaxial compression and cyclic loading of the briquette samples prepared with the predominantly inclined coal. The SEM and numerical The simulation software analyzes the source of acoustic emission events.The results show that the parameters of AE increase with the increase of the deformation of coal sample during uniaxial compression and show the maximum amplitude and the dense AE event region at the late stage of yielding, The AE curve and amplitude curve are similar to the uniaxial compression stress and strain curve, which can be used to determine the instability and failure of coal body in the field. With the increase of the number of cyclic loading, the AE event and its energy are presented Decreasing trend, and no AE events occurred during the unloading phase.The four microstructural changes were the sources of acoustic emission events generated by coal samples.