The Secondary Buckling and Design Criterion of Composite Laminated Cylindrical Shells

Even a weak disturbance caused by an asymmetric mesh is enough to break structural symmetry, which triggers the bifurcation buckling and post-buckling behavior of composite laminated cylindrical shells under compression loading by ABAQUS. The mesh perturbation is more objective and authentic; it will not destroy the original model structure in Finite Element Analysis, comparing with the traditional perturbation method by introducing the initial imperfections into the model. A series of numerical experiments are performed to investigate the influence of different types of asymmetric mesh on the predicted secondary buckling load. The predicted secondary buckling load agrees better with analytical solution than predicted primary buckling load and the results from the traditional perturbation method respectively. Therefore, secondary buckling load provides the key design criterion for composite laminated cylindrical shells. Primary and secondary post-buckling patterns of different complexity are explored, which agrees well with experimental buckling modes. Our major conclusions can be summarized briefly: different types of asymmetric mesh have little influence on the predicted secondary buckling load; Care must be exercised regarding the mesh density in order to produce the secondary buckling mode as well as the reliable secondary buckling load.