THE SCATTERING OF GENERAL SH PLANE WAVE BY INTERFACE CRACK BETWEEN TWO DISSIMILAR VISCOELASTIC BODIES

The scattering of general SH plane wave by an interface crack be-tween two dissimilar viscoelastic bodies is studied and the dynamic stress intensityfactor at the crack-tip is computed.The scattering problem can be decomposed intotwo problems:one is the reflection and refraction problem of general SH plane wavesat perfect interface(with no crack);another is the scattering problem due to the exis-tence of crack.For the first problem,the viscoelastic wave equation,displacement andstress continuity conditions across the interface are used to obtain the shear stressdistribution at the interface.For the second problem,the integral transformationmethod is used to reduce the scattering problem into dual integral equations.Then,the dual integral equations are transformed into the Cauchy singular integral equationof first kind by introduction of the crack dislocation density function.Finally,thesingular integral equation is solved by Kurtz’s piecewise continuous function method.As a consequence,the crack opening displacement and dynamic stress intensity factorare obtained.At the end of the paper,a numerical example is given.The effects ofincident angle,incident frequency and viscoelastic material parameters are analyzed.It is found that there is a frequency region for viscoelastic material within which theviscoelastic effects cannot be ignored.