Due to light weight, high performance, and increased service life, fiber-reinforced
composite materials are receiving wide attention as an advanced material in many
branches of engineering. Structural integrity of composite structures is affected by
the presence of flaws such as cracks and delaminations in the composite
material. In this paper, elastodynamic reciprocity relations are developed for
wave scattering by flaws, when guided waves are allowed to propagate in
fiber-reinforced composite plates. These relations are useful for checking the
accuracy of the numerical solution for the scattered wave field in ultrasonic
nondestructive evaluation of flaws in composite plate-like structural elements.
The classical elastodynamic reciprocity theorem is used to derive simple
reciprocity relations for reflected and transmitted wave amplitudes and the
corresponding energies associated with the wave modes in a plate with an
arbitrary stacking sequence. The derived reciprocity relations are used to
check the accuracy of the numerical solution for several example scattering
problems.
