Abstract
In order to study simple nondestructive inspection, dynamic response of a plate which includes a crack is studied by using numerical calculation. For numerical calculation, Boundary Integral Equation Method is employed mainly. In numerical calculation, a crack included a plate is treated as a two-dimensional crack. From numerical calculation, it is revealed that eigen frequency of the crack vary with the position of the crack. Eigen frequency of the crack becomes small with position of the crack approaching the tip of the plate. Wave radiating from a crack can be detected on the area above a crack. Existence of the crack has week effect on eigen frequency of the plate.
