线性节理对岩石电磁辐射传播的影响

Effect of linear joint on propagation of rock electromagnetic emission

基于岩石压电效应,依据应力波下电场值的表达式及应力波在节理处的透射解,获得垂直入射应力波作用下产生的电磁波在线性节理面前后的强度关系,并且研究节理参数、岩体电性参数以及入射波频率对电磁辐射传播过程中强度的影响。研究结果表明:电磁辐射的强度随节理初始刚度增大而增大,随频率增大而减小;电磁辐射强度随黏性系数的增加先减小后增大,这与黏性系数变化过程中所导致的电阻率的变化相关;电磁辐射强度随黏性系数变化的同时还受到频率的影响;当节理面两侧岩体性质不同时,电磁辐射强度的变化同时受到多种参数的影响,情况变得更加复杂。

Based on piezoelectric effect of rock and the electric field expression under stress wave and the resolution of the transmitted coefficients in the joint,the intensity variation of the electromagnetic emission（EME） before and after the linear joint under the normal incident stress wave was obtained.The effects of such parameters as initial joint stiffness,the electric parameters of the rock masses and incident frequency of wave on the intensity variation of the EME were investigated.The results show that the intensity of EME increases with the increase of joint stiffness and decreases with the increase of frequency;the intensity of EME decreases first then increases with the increase of viscosity coefficient,which relates to electric resistivity variation induced by viscosity coefficient change and frequency.When the rock properties on the two sides of the joint are different,the variation of EME intensity becomes complicated under the influence of many parameters.