Damage localization in a glass fiber reinforced composite plate via the surface interpolation method

11th International Conference on Damage Assessment of Structures

物理学;材料科学

Limongelli, M.P.^1 ; Carvelli, V.^1

Politecnico di Milano, Department of Architecture, Built Environment and Construction Engineering, Milan, Italy^1

关键词: Damage localization;    Discontinuous functions;    Frequency response functions;    Glass fiber reinforced composite;    Interpolation error;    Spline interpolation;    Surface interpolation;    Two-dimensional structures;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/628/1/012095/pdf
DOI  :  10.1088/1742-6596/628/1/012095

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

This work deals with the application to composite plates of the surface interpolation method (SIM) for damage localization. The procedure, which is a generalization to the two-dimensional case of the previously published Interpolation Damage Detection Method (IDDM), locates reductions of stiffness in two-dimensional structures such as plates. The method is based on the damage sensitive of a spline function accuracy in fitting the operational displacement shapes, relies on the so-called Gibbs' phenomenon for splines. This phenomenon occurs when a spline function interpolates discontinuous functions and consists in sharp oscillations and overshoots (values higher than those of the function to be interpolated) near a discontinuous point. The operational deformed shapes are recovered from frequency response functions (FRF's) measured at different locations of the structure during vibrations. The accuracy of the spline interpolation is measured by an error function defined as the difference between the measured and interpolated operational deformed shapes. At a certain location an increase (statistically meaningful) of the interpolation error, with respect to a reference configuration, points out a localized variation of the operational shapes thus revealing the existence of damage. The accuracy of the surface interpolation method is experimentally assessed by impact hammer tests on glass fiber/vinylester composite plates progressively damaged and using finite element numerical modelling.