Influence of statistical errors on damage detection based on structural flexibility and mode shape curvature

Damage detection procedures based on measured natural frequencies and building structure mode shapes are discussed in this paper. Modal curvature and structural flexibility approaches are tested. Attention is paid to the modal identification errors that influence damage detection. This problem is studied using a computer simulation of a simple supported beam. For practical cases, the peak picking method and its statistical errors are considered. In order to distinguish between true and false damage detection results, the Absolute Damage Index is proposed. Finally, the complexity of the problem in the case of a real building structure is presented.