Thermal-mechanical buckling of composite plates for aerospace applications

A closed-form solution is proposed for determining the buckling of composite plates under combined thermal-mechanical loading. The plates are subjected to a constant temperature increment, combined with applied displacement, while transversal in-plane expansion is restricted. The plates are studied using Von Kármán equations in combination with classical lamination theory, being the study limited to symmetric and balanced laminates. The problem is formulated in terms of in-plane displacement fields and solved using the Galerkin method. An analytical formula is obtained that relates critical temperatures to applied plate displacement. An example of a possible application is presented in the form of graph and is verified by finite element analysis. The obtained formula can be used during initial design for sensitivity analysis and optimization, and also for deriving specific buckling shapes.