Damped updated finite element model for damage detection

Stiffness-based structural health monitoring methods are widely used for detecting the damage in a structure. These stiffness-based structural health monitoring methods are based on identifying the change in stiffness of the healthy and damage structure due to changes in natural frequencies and modeshapes. These stiffness-based methods are not efficient for detecting small damages as the change in natural frequencies and modeshapes are negligible, however the damping characteristics of the structure are highly sensitive to such damages. In this paper, new damping-based damage detection method has been proposed. In the proposed procedure, non-proportional viscous damping model is used and the changes in damping matrix of the structure has been used to detect the damage in the structure. The proposed method uses the finite element model updating technique for detecting any change in damping matrix due to structural damage. The proposed procedure will be able to detect both the location and the extent of the damage in the structure. Numerical and experimental case studies are presented to demonstrate the effectiveness of the proposed method. The results have shown that the proposed damping-based damage detection procedure can be used for accurately detecting damage in a structure.