Damage Detection in Beam Structures Based on Curvature Change Estimated from Incomplete Mode Shapes

In this work, a procedure for damage localization and quantification in beam structures is presented. The proposed technique exploits the variations of the curvature between healthy and damaged structures, computed from the flexibility matrix. The flexibility matrix is approximated using the lowest structural frequencies and mode shapes, which can be easily derived on-site from vibration-based monitoring of the structure. Since in real-case scenarios structures can be instrumented only with a limited number of sensors, a procedure based on the expansion of the measured modal components is proposed. The presented technique is verified by testing two beam structures affected by different damages in terms of position and extension.