Modal plot-System identification and fault detection

Abstract

The damage identification is one of the primary concerns in structural health monitoring. Among the available studies, various authors have proposed several approaches for damage detection as well as certain parameters to be monitored (damage indicators) based on the Output only Modal Analysis. In this study, Level 0 fault detection is investigated by using modal properties. The utilization of modal properties has been established since the 1970s-1980s in a number of configurations. Within the context of this study, novel concepts and parameters such as the Modal Plot, the Count Plot, and the Modal Zones are introduced for system identification and damage detection. Modal parameters are identified via the modal and count plots, and the damage presence is detected from the modal zones in the modal plot. The modal plot is a method that contributes to the stabilization diagrams, and the count plot is an alternative approach for the power spectral density diagrams. Moreover, the modal zone is observed as a damage sensitive parameter in the experimental study.