Nonlinear dynamic buckling analysis of imperfect viscoelastic composite laminated plates

The aim of this paper is to study the effects of linear viscoelastic behavior on dynamic buckling response of imperfect composite laminated plates subjected to in-plane dynamic loads by implementing semi-analytical finite strip method (FSM). The semi-analytical FSM converges with a comparatively small number of strips and correspondingly small number of degrees of freedom. Thus, it is usually implemented more easily and faster than many other computational methods. The governing equations are derived by using classical laminated plate theory (CLPT) and the behavior of plate is assumed to be geometrically nonlinear through Von-Karman assumptions. The Newmark's implicit time integration method in conjunction with the Newton-Raphson iteration are employed to solve the nonlinear governing equation. A Kelvin-Voigt viscoelastic model is considered, and the effects of viscosity coefficient, thickness of the layers of the composite plate and boundary conditions on the nonlinear dynamic buckling response are discussed. In order to justify the accuracy of the results, some of them are verified against those available in other sources. It is also shown that the nonlinear dynamic buckling response of an imperfect viscoelastic composite laminated plate is significantly different from the elastic one by considering different viscosity coefficients.