Damage Detection in a Timber Beam

Abstract

Many timber bridges in Australia are old and structurally deficient. To avoid catastrophic failure of structures, development of a reliable damage identification and structural health monitoring for these bridge structures is one of the most important keys in maintaining the integrity and safety of the structures and users. Among various proposed damage identification algorithms, the methods based on vibration of structures have shown great potential. However, despite a number of vibration-based damage identification algorithms being proposed, and some being applied in laboratory or in the field, detailed studies on changes to dynamic behaviour of timber bridges are still in their early stages of development. Furthermore, structures subjected to different damage have also not been closely and systematically investigated. Hence, in this paper, 'multiple damage location detection' of a timber beam is numerically addressed. A finite element model is developed to acquire the modal parameters of the beam. Three types of damage detection algorithms were evaluated for multiple damage configurations. The quality of the damage identification with the three different detection algorithms is discussed. The mode shape curvature based method proves to be a reasonably good damage detection and health monitoring tools for multiple damage locations.