Non-linear free vibration of laminated composite plate with random material properties

Composite laminates are widely used in construction of mechanical, aerospace, marine and automotive structure. These structures exhibit inherent random dispersion in material properties, as absolute control of production process is neither feasible nor economical. Some composite structures are subjected to large amplitude vibration during their working life that may lead to non-linearity in the response. The present paper analyses the effect of material parameter dispersion on the large amplitude free vibration of especially orthotropic laminated composite plates. The basic formulation of the problem has been developed based on the classical laminate theory and Von-Karman non-linear strain–displacement relation. The system equations have been obtained by using Hamiltonʹs principle and the solution has been found by term wise series integration. Perturbation technique has been used to obtain the second order response statistics. Typical results have been presented for a plate with all edges simply supported. Effects of side-to-thickness ratio, aspect ratio, oscillation amplitude and mode shape along with change in standard deviation of material properties have been investigated for cross-ply symmetric and antisymmetric laminates.