Post-Failure Analysis of Composite Cylindrical Panels under Compression

In this study, the most conservative stiffness degradation method called the complete unloading model is used for the progressive failure analysis after the buckling of composite shell structures. To incorporate the complete unloading-failure model into the post-failure analysis of shell structures under compression, a modified arc-length control method is presented. In the method, unlike the previous arc-length methods, discontinuity of equilibrium path due to the abrupt change in stress and stiffness by failure of laminates is included in the determination of arc-length. Numerical examples considered are composite cylindrical panels under compression with various stacking sequences. The results of the numerical examples show the proposed numerical method can be extensively used for the progressive-failure analysis of composite shell structures after snap-through compression buckling.