Identification of stiffness properties of composite tubes from dynamic tests

The identification of the stiffness properties of typical laminated composite tubes from dynamic tests is presented. Unknown coefficients are identified by a technique of model updating. The fomulation is based on the minimization of the eigensolution residuals (sensitivity method). Errors of generalized masses are considered. The technique allows for the simultaneous identification of several properties from a single test. Stiffness properties of extension, bending/twisting and transverse shear are identified. Important points of the model updating of tubes in dynamics are addressed: potential energy evaluation, placement of sensors and the problem of multiple eigenvalues. Results obtained by numerical simulation show the efficiency of the proposed method.