Study of the Characteristic of Composite Sandwich Panel with Cut-out under Compression Load

Composite materials are used in aerospace structures due to their considerable bending stiffness and strength-to-weight ratio. A composite sandwich is composed of face-sheets and an aluminum core. Launch vehicle structures have cut-out areas through which to check the status of the payload and electric equipment. Cut-out areas reduce the structural stiffness of the launch vehicle structure. The shapes of the cut-outs are circular, square, oval_V(in which the major axis is vertical) and oval_H(in which the major axis is horizontal). In this paper, compression tests and FEM analysis were performed for composite sandwich panels with various types of cut-outs. To verify the failure strength, the results of compression tests and FEM analysis were compared. Results of compression tests and FEM analysis show that the oval_V shape has the maximum load and strain compared to the other shaped cut-outs.