Experimental and analytical investigation of failure and failure progression in composite Pull-off specimens

摘要

Thin-walled stiffened composite structures are commonly used in aerospace structures. Due to the complex properties of laminated fibre-reinforced composites, the reliable simulation of the mechanical behaviour has become more and more important, in order to reduce costs during design process by minimizing the testing effort. For the prediction of the mechanical behaviour up to collapse, it is inevitable to take failure and failure progression into account. In laminated fibre-reinforced composites, a common failure type is delamination, due to the low strength perpendicular to the layers of the laminate. Loaded in compression or shear, thin-walled stiffened structures tend to buckle. Even after first buckling of the skin, the load can still be increased until failure of the stiffeners. Initiation of stiffener failure may be delamination or debonding of stringer foot and skin. Therefore, prediction and simulation of skin-stiffener separation is of particular interest.