Optimisation of geometrically non-linear composite structures based on load-displacement control

摘要

A design optimization methodology for beam reinforced composite structures with non-linear geometric behavior is proposed. The formulation involves displacement, stresses, bucking and size constraints. The Newton-Raphson iterative procedure and the arc-length method are used for tracing equilibrium path and later updating the tucking load and the first ply failure load. The proposed sensitivity analysis model is based on an approach of the adjoin variable method for structures with non-linear geometric behavior. The optimal design performs on a multilevel scheme based on structural efficiency maximization exploring the anisotropy properties of the composites and weight minimization using the ply thickness and the cross-section variables of the stiffeners. To demonstrate the applicability of the proposed developments, optimization problems considering first ply failure and buckling conditions are presented.