DELAMINATION BUCKLING OF A SHORT ORTHOTROPIC TUBE UNDER AXIAL-COMPRESSION

A model is selected for the study of delamination buckling of a short laminated orthotropic tube under axial compression. Delamination is as sumed to exist prior to loading and it spans the entire circumference. On the basis of total Lagrangian description and axisymmetric assumpt ion, a nonlinear finite element method is formulated to examine nonlin ear post-buckling behavior. Then, for treating the contact of delamina tion face caused by the effect of curvature, the nonlinear finite elem ent program is associated with a quadratic programming procedure. Usin g the path independent J-integral defined for axisymmetric finite defo rmation, the energy release rate is calculated. The load-carrying capa city of the delaminated tube and the stability of delamination growth are examined in terms of the critical buckling load and the energy rel ease rate, respectively.