岩石中声波衰减特性的理论与实验研究

Theoretical Analysis and Experimental Study on the Attenuation Behavior of Acoustic Wave in Rocks

本文从岩石试件在单轴压应力作用下的声波衰减现象出发,运用损耗介质的本构方程及粒子应力场理论,结合对含有裂隙岩石的有效弹性刚度系数的能量分折,建立了岩石介质中声波衰减特性与单轴压应力间的理论函数关系,即对较均质、致密的岩石,声波衰减系数比可近似地表示成应力的二次多项式关系。同时,声波衰减系数还与岩石的孔隙率、裂隙谱、弹性模量和泊松比等有关。最后,由实验数据证明本文所建立的声波在岩石中的衰减特性理论是合理的。

This paper established the basic law of attenuation of the acoustic wave propagating through the rock under uniaxial compressional stress. The theoretical analyse showed that for a given rock type the relation between stress and attenuation coefficient ratio could be expressed approximately as second-order polynomials. Important parameters involved were porosity, crack spectra.Young's modulus, and Poisson's ratio of each type of rock. And finally, the rationality of the proposed theory was confirmed by the experimental results.