A new damage estimation method for carbon fiber reinforced polymer based on electrical impedance tomography

Damage estimation is vital for monitoring the remaining life of carbon fiber reinforced plastic/polymer (CFRP). As a non-invasive, non-radiative, and low-cost method, electrical impedance tomography (EIT) is increasingly investigated for the purpose of structural health monitoring of CFRP. The commonly used EIT method is limited by the image accuracy since it estimates the damage just through a reconstructed image. In this paper, a damage estimation method (DEM) is proposed to quantify the damage location and area. First, each damage is fitted into a two-dimensional Gaussian function through edge fitting. Then, the parameters of the Gaussian function are optimized with the two-norm regularization method. Finally, the damage location and area are estimated with the parameters of the Gaussian function. The accuracy of the DEM is directly evaluated in terms of location error and area error. Both simulation and experimental results demonstrated the potential of the proposed method in providing damage estimation information.