Nonlinear Finite Element Analysis Of Progressive Failure Of Cylindrical Composite Shells

With the composite materials being widely used in the aerospace industry, the buckling and post-buckling of composite plates and shells have been become a major concern by lots of engineers. Cylindrical shell and cylindrical shell panels are very common shell structures. The buckling of cylindrical shells is relatively simpler than that of other shells, but the research results can be readily extended to the cases of other general shells. The purpose of this investigation is to establish a modeling strategy for accurately predicting the buckling and the progressive failure in the post-buckling of cylindrical composite shell panels. Finite element method is employed and Hashin failure criterion is used. A user material subroutine based on the failure criterion is developed and inserted into the commercial finite element software ABAQUS. Cylindrical composite shell panels subjected to a transversely concentrated load at its centre is analyzed. Two straight edges of the panel are elastically supported and two curved edges are free. Finite element results are compared with the existing experimental data in the literature to investigate the effect of the elastically supported conditions and the stress concentration caused by the concentrated load. A reasonable criterion for simulating the correct elastic boundary condition is proposed. It is found that if the elastically supported and the stress concentration at the small area of the concentrated load point are considered in the modeling, the simulated results fairly close to the experimental data and are much better than the existing predictions. Therefore, the rationality of the established modeling strategy is validated.The research is partially supported by the Chinese Natural Science Foundation under the contract number of 50675100.