A mixed sensitivity method for structural damage detection

Structural damage detection using measured dynamic data has emerged as a new research area in civil, mechanical and aerospace engineering communities in recent years. In this paper, a mixed sensitivity method is presented to identify structural damage by combining the eigenvalue sensitivity with the flexibility sensitivity. The sensitivity of structural flexibility matrix is firstly derived by Neumann series expansion and then the eigenvalue sensitivity together with the flexibility sensitivity are combined to calculate the elemental damage parameters. The presented mixed perturbation approach is demonstrated and compared with the eigenparameter sensitivity method on a 31-bar truss structure. It has been shown that the proposed procedure is simple to implement and may be useful for structural damage identification. Copyright (C) 2008 John Wiley & Sons, Ltd.