A viscoelastic plate theory for the fast modelling of Lamb wave solutions in NDT/SHM applications

Abstract

Guided ultrasonic waves have many useful properties that can be exploited for non-destructive testing (NDT) and structural health monitoring (SHM) applications. However, much information and analysis regarding the generation and propagation of these waves is needed before automatic processing and analysis techniques can provide useful information for reliable fault monitoring. Moreover, the knowledge of dispersion characteristics is crucial for the optimization of sensor networks in terms of sensor placement and number of sensors. On that account, the present work introduces a higher order plate theory for modelling disperse solutions in viscoelastic fibre-reinforced composites. This approach offers a higher computational efficiency and simplicity in comparison to traditional exact elasticity methods, while providing an adequate description of the structure's global response in the low frequency range which is the most used in Lamb wave applications. The proposed method was applied to several examples in order to obtain numerical results in elastic and viscoelastic anisotropic plates. Some comparisons to experimental data are presented, and the effectives and limitations of the method are discussed.http://dx.doi.org/10.5755/j01.u.66.2.524