Stability and optimal design of laminated plates with internal supports (Q675459)

The stability of symmetrically laminated rectangular composite plates with internal line supports and point supports is analyzed using the Rayleigh-Ritz method. Polynomial approximation functions are selected to satisfy both the boundary conditions along the edges and the zero displacement constraint along any number of internal line supports. Point supports are introduced using the Lagrange multiplier technique. The elastic and geometric stiffness matrices are obtained exactly, and the plate constitutive equations are expressed in terms of four lamination parameters to describe all symmetric laminates regardless of the number of plies. An exact solution for simply supported plates with equal length spans and no bending-twisting coupling is used to check the accuracy of the model. Extensive results are presented, and the effect of the number of plies, plate aspect ratio, material properties and lay-up are examined in detail.