A numerical–experimental study for structural damage detection in CFRP plates using remote vibration measurements

Abstract

The performance and behavior of composite structures can be significantly affected by degradation and damage. Degradation can be caused by exposure to environmental conditions and damage can be caused by handling conditions, such as impact and loading. Such damages are not always visible on the surface and could potentially lead to catastrophic structural failures. This paper addresses the specific challenge of using numerical simulations to assess damage detection techniques applied to composite laminated plates. This study aims to solve the direct and inverse problem of damage detection by combining numerical and experimental data. Finite element analysis was carried out to analyze the direct problem of mechanical response. Heuristic optimization techniques were used to solve the direct and inverse problem by combining data from a model with that of the experiment to identify structural damage. This study also sought to update the finite element model by minimizing the objective function. The structure studied was constituted of a composite plate. Two damage models were used: (i) circular hole and (ii) delamination (local stiffness reduction). The results of the optimization algorithms show good efficacy in the detection of structural damage, identifying the damaged location on the structure and also quantifying the size of the damage in real composite structures. A method has been proposed to identify the damage in CFRP plates using remote vibration measurements. Furthermore, the numerical simulation and experimental tests have been used to verify the method.