煤体剪切破坏过程电磁辐射与声发射研究

Study on Electromagnetic Radiation and Acoustic Emission in Shearing Process of Coal

用剪切实验台和电磁辐射、声发射接收系统对煤体剪切破坏的电磁辐射、声发射特征进行了研究 .结果表明 ,煤体剪切破坏过程中电磁辐射和声发射有两种类型 :一种是在加载初期出现较高的强度 ,加载中间阶段有较为平静的区域 ,主破坏发生前又逐渐增强 ,破坏时出现较高的强度 ,破坏后逐渐减弱 ;另一种是随应力增大电磁辐射和声发射持续增强直至破坏 ,破坏后减小 .试验结果与预测冲击矿压、煤与瓦斯突出等动力灾害的现场测试结果吻合 .

Using the shearing experimental equipment and the receiving systems of electromagnetic radiation (EMR) and acoustic mission (AE), the characteristics of EMR and AE during the shear and fracture of coal were investigated. The results show that there are two kinds of EMR and AE in the shearing process of coal. The one is: increasing gradually at the beginning of loading, having a calm zone in the middle stage of loading, enhancing gradually before fracture, very intense at the moment of fracture, and decreasing after fracture; the other is: increasing continually with the increase of stress until coal samples fracture and decreasing after fracture. These characteristics of EMR agree with the practical observation of forecasting rock burst and coal-gas outburst with the EMR method.