ABSTRACT
Numerical analysis and experimental studies on the use of flexural waves for nondestructive evaluation of cracks and delaminations in beams of isotropic and anisotropic materials are introduced in this chapter. Computational inverse procedures employing genetic algorithms (GAs) and neural networks (NNs) for determining the geometrical parameters of the crack and delamination are detailed. In these procedures, the strip element method (SEM) for composite laminates, methods based on the beam model of wave propagation, and the finite element method are used as forward solvers. The study is conducted according to the following procedure:
• Forward solvers (SEM code and beam model) are introduced first. • Intensive experiments are carried out to reveal the sensitivity of the
measured responses to the geometric parameters of the cracks and delaminations. The experiments are also used to verify the forward solver to be used for inverse analysis. Furthermore, the experiments are used to estimate roughly the geometrical parameters of the cracks and delaminations.
