On the transient response of actively repaired damaged structures by the boundary element method

The transient fracture mechanics behavior of damaged structures repaired through active piezoelectric patches is presented in this paper. The analyses have been performed through a boundary element code implemented in the framework of piezoelectricity to take account of the coupling between the elastic and the electric fields, which represents the peculiar feature of piezoelectric media. The multi-domain technique has been also involved to assemble the host structures and the active patches and to model the cracks. Moreover, the patches have been considered elastically bonded to the damaged structure by means of a zero thickness adhesive layer. This has been achieved through the implementation of an interface spring model which has allowed, coupled with an iterative procedure, to prevent overlapping at the interface between the host structure and the active patch as well as between the crack surfaces. The Dual Reciprocity Method (DRM) has been used in the present time dependent application for the approximation of the domain inertia terms. Numerical analyses have been carried out in order to characterize the dynamic repairing mechanism of the assembled structure by means of the computation of the dynamic Stress Intensity Factors