In order to improve the interface strength between composite ribs and skin

stitching is an effective method. Finite element model (FEM) analysis and axial compression test were carried out on the non damage stitched stiffened panel and the impact damage stitched stiffened panel. The cohesive zone model was used to simulate the interface and the bonding element was used to simulate the stitching for FEM analysis. The deviation between the test results and FEM results is no more than 8.5%

which shows that the FEM of cohesive model and bonding element is feasible. The test results and the FEM results both show that the stitching has no significant effect on the compressive capacity of composite stiffened panel.