DYNAMIC INSTABILITY OF SHEAR-DEFORMABLE VISCOELASTIC LAMINATED PLATES BY LYAPUNOV EXPONENTS

The dynamic stability of viscoelastic laminated plates, subjected to a harmonic in-plane excitation, is analyzed. The viscoelastic behavior is caused by the polymeric matrix of the fiber-reinforced material, and a micromechanical analysis provides the time-dependent relaxation functions of the unidirectional lamina. The Boltzmann representation involved in the stress-strain relations of the laminated plate leads to an integro-differential equation of motion, obtained within the first-order shear deformation theory. For this case, a dynamic stability analysis which employs the concept of Lyapunov exponents is performed, and is shown to be very efficient.