A two-stage multi-damage detection approach for composite structures using MKECR-Tikhonov regularization iterative method and model updating procedure

Abstract Modal kinetic energy (MKE)-based feature has been widely employed for the selection of optimal sensor layout; however, its development to the field of structural damage identification has still received less attention. The article hence is performed to fill in this research gap by proposing a two-stage multi-damage detection approach for composite structures by using MKE change ratio (MKECR) and model updating procedure, taking into consideration both spatially-incomplete measurements and noise. In the first stage, the MKECR-based method is used to construct the damage equation set and then a Tikhonov regularization-based iterative technique is employed to solve this equation set for the purpose of damage localization. In the second stage, the model updating procedure using Lightning Attachment Procedure Optimization (LAPO) algorithm is established and implemented for damage severity estimation, in which the MKE feature is introduced here as an objective function for the first time. Finally, the performance of the proposed two-stage damage detection approach is investigated through two numerical examples of different composite structures (beam and plate). The obtained results from the simulation examples reveal that the proposed identification approach can identify multi-damage locations and estimate their damage severities with satisfactory accuracy, even under spatially-incomplete measurements and high measurement noise.