Diffractions of flexural waves by a cavity in an elastic plate

Based on Mindlin's theory of flexural motions of plates, which takes into account the rotatory inertia and shear effects, diffractions of flexural waves by a circular inclusion in an elastic plate are investigated. An incident plane flexural wave passing through the inclusion is scattered into three types of flexural waves. From the combined incident and scattered waves, moment and shear on the boundary of the cavity are computed. They are the dynamical moment and shear concentrations in a vibratory plate with a cavity. Moment concentration factors are found to be lower in the dynamic case than in the static case.