Diffraction of elastic waves by a subsurface crack (antiplane motion)
Abstract
A rigorous theory of the diffraction of SHwaves by a stressfree crack embedded in a semiinfinite elastic medium is presented. The incident timeharmonic SHwave is taken to be either a uniform plane wave or a cylindrical wave originating from a surface linesource. The resulting boundaryvalue problem for the unknown jump in the particle displacement across the crack is solved by employing an integral equation approach. The unknown quantity is expanded in a complete sequence of Chebyshev polynomials. By writing the Green function as a Fourier integral, an infinite system of linear, algebraic equations for the expansion coefficients is obtained. Numerical results are presented for the particle displacement at the surface of the halfspace, the far field radiation characteristic, the scattering crosssection of the crack and the dynamic stress intensity factor at the crack tips, for a range of geometrical parameters.
 Publication:

Journal of Sound Vibration
 Pub Date:
 April 1984
 DOI:
 10.1016/0022460X(84)904218
 Bibcode:
 1984JSV....93..523N