含水量对煤岩电磁辐射特征的影响

利用MTS815电液伺服岩石试验系统对不同含水量原煤试样进行加栽破裂试验，测试了试样变形破裂过程中的电磁辐射信息，分析了自然原煤样及不同含水量煤样受栽破坏时的电磁辐射特征及水分对电磁辐射在煤岩介质中传播的影响．结果表明，随含水量的增加，煤岩产生的电磁辐射强度减小；在煤岩破坏过程中，电磁辐射的阶段分布特征发生变化，含水煤样在应力峰值前电磁辐射信号明显比自然原煤丰富．煤层含水量的增大，使得煤岩介质电阻率降低，导电性能增强，电磁辐射在煤层中的趋肤深度减小，即在煤层中传播距离变小．研究结果表明，水对煤岩电磁辐射的产生和传播的影响是显著的，因此，在煤矿现场的应用中必须考虑到煤层水分对电磁辐射的影响．

Effect of Moisture Content on Electromagnetic Radiation Characteristic of Coal or Rock

The deformation and fracture experiment of coal sample with different moisture content was made usingthe MTS815 type electro hydraulicservo rock experiment system,and the electromagnetic radiation(EMR) information was tested and acquired during the experimental process.The EMR characteristic of natural raw coal and raw coal with different moisture contentin the course of deformationand fracture under load and the effect of water on the propagation of EMR in coal were also studied.The results show that the EMR intensity of coal decreases along with the increasingof moisture content.The phase distribution characteristic of EMR during the deformation and fracture process of coal changes and the EMR signalof the aquiferousraw coal is more abundant than that of naturalraw coal before the value of the loading stress is maximum.The larger the moisture content becomes,the lower the coal resistivityis,so that the coal conductivecapability enhances and the skin depth(the propagation distance of EMR in coal seams) decreases.Therefore,the effect of water on the generation and propagation of EMR is obvious and the influence of coal seam moisture on EMR must be studied in coal mine.