Damage localization of beams based on measured forced responses

摘要

The early detection and localization of damages is essential for optimal operation and efficient maintenance of structures. The methods for damage detection and localization should be able to work for wide range of frequencies since the frequency of oscillation cannot be controlled in majority of real-life applications. The current work presents two new approaches for damage localization of beams. The approaches are based on comparison of time responses of intact and damaged beams. The first approach is called selective index method and considers the curvature of the beam and its time derivatives. The second approach considers the fact that the damage of the beam introduces discontinuity of the shear force and uses these discontinuities to localize the damage. Two types of damages are considered - damage modeled by reduced thickness and by reduced stiffness. Several examples are presented and it is demonstrated that both approaches localize correctly the damage.