Buckling Of Composite Beams With Two Enveloped Delaminations: Lower And Upper Bounds

摘要

Lower and upper bounds of the buckling load of a composite beam with two enveloped delaminations are obtained from newly developed analytical models. The characteristic equation, governing the delamina-tion buckling is derived by using Euler-Bernoulli beam and classical lamination theory, performing proper linearization and by imposing the appropriate continuity and boundary conditions. Linear and non-linear finite element analyses carried out to verify the accuracy of the developed model. S-shaped buckling mode dominates more than a single hump buckling mode in the case of upper bounds, whereas, for lower bounds of the buckling load, mixed and/or local buckling modes are observed.