Damage Detection in Beam-Like Structures Using Mode Shape Curvature Change-Based Method

In this paper, the mode shape curvature change-based method is improved to detect the damages in beam-like structures. A steel beam, whose damages are simulated by reducing the bending stiffness of the beam's elements, is analyzed for vibration with undamaged and damaged cases. Additionally, a damage threshold is investigated to detect the damage zone and evaluate the accuracy of the detection method. The effectiveness of the improved damage detection method is evaluated through a damage index. This study also proposed using the Spline function to smooth data and perform interpolation. Furthermore, the mode shape curvature is calculated by using two different functions, which are a central difference approximation algorithm and an alternative algorithm, to make a comparison about the effectiveness of damage detection. This paper shows that the mode shape curvature change-based method, using a central difference approximation algorithm, which is combined with the Spline function, gives highly accurate results of the damage detection in both the damage's occurrence and location.