Mechanisms and Modeling of Delamination Growth and Failure of Carbon-Fiber Reinforced Skin-Stringer Panels

摘要

The main objective of this work was to investigate and predict the behavior of damaged structural elements (skin-stringer panels). The study combined characterization through testing with fractographic analysis, and analysis of delamination using the finite-element method. The experimental studies entailed investigation of damage growth from embedded skin defects in panels under compres-sive load, and the subsequent structural failure. Parameters such as defect size, location with respect to substructure and through-thickness position were studied. Local delamination and global panel buckling were modeled, and the resulting delamination growth was simulated using a moving mesh technique. The results illustrated the importance of the location of the 90° plies to the damage evolution, and the criticality of global buckling and stringer detachment in the structural failure. The understanding gained from both the experimental investigations and numerical simulations has led to guidelines for realistic modeling and rules for designing damage tolerant structures.