Collapse Analysis of Cylindrical Composite Panels with Large Cutouts Under an Axial Load

摘要

In order to better understand teh collapse properties of composite shells, an analysis of cylindrical panels with large cutouts (11&18% of panel area) was conducted using a finite element program (STAGSC-1). These results were then compared to experimental findings. Cutout size, loading methods, vertical boundary conditions, and imperfections were varied to see how each affected the collapse load. In addition, the release of residual strain due to placing the cutout within the panel was evaluated. It was found the panel collapsed at a lower value when the applied force was a uniform load as compared to a uniform displacement. The decrease in collapse load with increased cutout size is less dramatic for the displacement condition. Initial imperfections wer found to reduce the collapse load, but not to the extent seen for panels without cutouts. Fixing circumferential freedom along the vertical boundaries resulted in increased collapse loads as compared to leaving it free. Compared to experimental findings, STAGSC-1 was seen to progressively underestimate collapse load as cutout size increases. Keywords: Composite Materials, Cylindrical Panels, Cutouts, FInite Elements, NOnlinear Analysis.