层状介质中多个非共面Griffith裂纹的弹性波散射问题研究

本文利用积分变换的方法,研究了层状介质中多个非共面Griffith裂纹的弹性波散射问题,导出了当入射波分别为P(SV)波及SH波时的散射对偶积分方程,并以双覆盖层半空间中的双裂纹为例,对反平面剪切波的散射场进行了求解和较为详尽的分析。最后通过数值计算,得到了许多有关的动力学特性曲线,从而揭示了层状介质中多裂纹弹性波散射问题中的某些内在规律。

SCATTERING OF ELASTIC WAVES BY MULTIPLE NON-COP-LANE INTERFACE GRIFFITH CRACKS IN A LAYERED MEDIUM

In this paper an analysis of scattering of elastic waves by multiple non-coplane interface Griffith cracks in a layered medium is presented. Making use of Fourier integral (transform, the problem is reduced to a set of dual integral equations which can be reduced further to a set of singular integral equations and then solved by numerical methods. As an example, the scattering of SH waves by two cracks in two layered half-space has been investigated in more detail. The features of the scattering waves at the crack-tips and far-fields are discussed. And finally, the numerical values of the dynamic stress intensity factor at the rim of cracks and the amplitudes of the far-field displacement for the first two modes are plotted versus the frequency of incident waves.