Some insights into the dynamics of defective structures

As a general principle, it should be assumed that defective structures will exhibit nonlinear response behaviour. The primary activity of the Cardiff research group over the last ten years has been the identification of the types of non-linear phenomena encountered in the dynamics of defective structures together with an estimation of their observability, albeit in a qualitative sense. A wide range of classical non-linear effects from subharmonic oscillations to chaotic vibrations has been observed. It is argued that structural integrity assessment can be enhanced by incorporating these non-linear effects into damage assessment criteria.