Improved modal characterization of the constitutive parameters in multilayered plates

This paper presents an accelerated modal numerical–experimental identification method for estimating the elastic parameters in multilayered composite plates. The proposed algorithm is based upon a contact-free measurement setup and a finite element model including a shear deformation theory of variable order. By minimizing selectively, according to the nature of the parameter, the residuals between the numerical and experimental frequencies and mode shapes, the method takes advantage of the sensitivity of the constitutive properties on the modal data. This optimization in two steps instead of a traditional one-step approach improves the accuracy of the elastic parameters estimated and enhances the convergence rate of the characterization method, as shown in two test cases applied to a unidirectional multilayered carbon/epoxy plate.