Finite strip analysis of laminated plates with general initial imperfection under end shortening

Description of a finite strip method is given for predicting the post-buckling response of rectangular laminated plates when subjected to progressive end shortening. Initial imperfection in very general shape is also included. Polynomial expression is used to simulate the actual imperfection along each nodal line while the deformations are represented by trigonometric series. The analysis, under the assumption that thin plates are used, is based on the classical plate theory. Geometric non-linearity is introduced in the strain-displacement equations in the manner of the von Karman assumptions. The Newton–Raphson method is used to solve the non-linear equilibrium equations. A number of applications involving both isotropic and laminated plates are described to investigate the effects of initial imperfection.