MODE SHAPE BASED METHODS FOR IDENTIFICATION OF DELAMINATION IN COMPOSITE BEAMS

In recent years, structural health monitoring is gaining high importance in conjunction with damage assessment and safety evaluation of structures. Delamination is a common type of damage in fibre reinforced composite laminates used for mechanical and aerospace structures. It is usually an internal and hidden type of damage which may lead to catastrophic failure without prior warning. Early detection of this type of damage is essential. The damage detection techniques proposed here use the displacement mode shapes of the beam, which are then converted to respective curvature modes and modal strain energy. The damage indices based on these parameters are also evaluated for locating the delamination after applying gapped smoothing techniques to the curvature mode shapes. This work presents a numerical study on detection of delamination damage in composite beams, where the proposed methodology is applied for identifying delamination in a three-dimensional numerical finite element model of a composite beam.