Three-dimensional elasticity solution for buckling of composite laminates

Three-dimensional elasticity solutions are presented for the buckling of simply supported orthotropic and laminated composite plates. A uniform prebuckling stress assumption is made for composite laminates, which is equivalent to the membrane assumption used in plate theories. The closed-form expressions for the displacements and stresses are derived and a nonlinear eigenvalue problem is constructed which is used to solve for the critical load. The results obtained from the elasticity solution are compared with the critical loads furnished by the classical laminate theory and the refined third-order shear deformation theory. The solution provides a means of accurate assessment of existing two-dimensional plate theories.