岩石破裂电磁辐射频率与岩石属性参数的关系

为进一步明确岩石破裂电磁辐射频率特征，基于岩石破裂电磁辐射是由岩石破裂时传播裂纹引起原子扰动产生的假说， 通过断裂力学理论中小范围屈服条件下张开位移法计算岩石破裂时的裂纹宽度，由单脉冲电磁辐射频率与裂纹宽度之间的关系，研究电磁辐射频率与岩石属性参数之间的关系，并给出了它们之间的关系表达式;单独讨论了不同属性参数对电磁辐射频率的影响.结果表明，电磁辐射频率随弹性模量增大而增大,随岩样尺寸和强度增大而减小,随泊松比的变化、岩石弹模的不同电磁辐射频率有变化;当弹模较小时，泊松比的影响也较小，而当弹模很大，即岩石刚度很大时，泊松比的增大会导致频率的增大；裂纹初始长度的变化受试件尺寸的影响，进而影响频率，当尺寸较大时，裂纹长度对频率影响较小，当尺寸较小时，频率随裂纹长度增大而增大.通过计算几种常见岩石破裂时电磁辐射频率值发现，岩石破裂时电磁辐射频率达到105 Hz量级，这与现有的实验结果相吻合.

The relation between the frequency of electromagnetic radiation (EMR) induced by rock fracture and attribute parameters of rock masses

In order to make clear the characteristic of the frequency of the EMR induced by rock fracture further, based on the hypothesis of the EMR created by atomic perturbation aroused by propagating crack during rock fracture, the relation between EMR frequency and rock′s attribute parameters has been obtained by the relation between the EMR frequency and crack width calculated using the Crack Opening Displacement method. The dependence of the EMR frequency on each of the attribute parameters has been discussed. The results show that EMR frequency increases with the increase of the elastic modulus; EMR frequency decreases with the increase of the size and strength of rock samples. The EMR frequency changes with the Poisson ratio and the elastic modulus. When the elastic modulus is small, the effect of the Poisson ratio on the frequency is also small; when the elastic modulus is very large, that is the stiffness of the rock is very large, the increase of the Poisson ratio results in the increase of the frequency; when the size of rock samples is large, the effect of the initial length of the crack on the frequency is small, however, the frequency increases with the crack length when the size of rock samples is small. And the fracture induced EMR frequency values have been calculated for several kinds of common rocks. It is shown that the order of the magnitude of the frequency of the single pulse EMR reaches 10⁵ Hz. The results in this paper are in agreement with the experiments in the reference ［11］.