Application of a new energy-based collocation method for nonlinear progressive damage analysis of imperfect composite plates

In this paper, an efficient simple numerical method, known as energy-based collocation, is presented to analyze the nonlinear behavior of a geometrically imperfect composite plate subjected to compressive in-plane load while taking into account progressive damage phenomena. This method is based on the energy approach, in which the plate is discretized into the Legendre-Gauss-Lobatto points. The nonlinear governing equations are based on the First-order Shear Deformation Theory (FSDT) and the assumptions of large deflection. The system of nonlinear algebraic equations is solved using the quadratic extrapolation technique. Plates with various boundary conditions and different ranges of thickness are investigated. Hashin and Rotem failure criteria are established to predict failure. Several properties degradation models are proposed for the developed failure mechanism and description of ply degradation. The analysis is performed by a computer program developed based on FORTRAN language. The accuracy of the developed procedure is assessed by comparing numerical results taken from previous works.