Abstract: In this paper, based on the governing equation for flexural waves of orthotropic plates, diffraction of elastic waves by cutouts and dynamic stress concentrations in the thin plate has been studied. An analytic method to solve dynamic stress concentrations in the plate with an arbitrary cutout is established. An asymptotic expansion solution that satisfies the boundary conditions on the edge of cutouts is obtained. Therefore the solution of the problem can be normalized by means of this method. Numerical re...